Article

Hydration in sport and exercise: Water, sports drinks and other drinks

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Abstract

There is evidence to suggest that exercise‐induced dehydration can have a negative impact on exercise performance, and restoration of fluid balance should be achieved after exercise. It is equally well known that muscle glycogen must be restored after exercise if subsequent performance is not to be negatively affected. Sports drinks are ideally placed to fill both these roles. However, while muscle glycogen restoration can be comfortably achieved by consumption of solid food, the same is not true for restoration of hydration status. Clear evidence is available that drinking during exercise can improve performance, provided that the exercise is of sufficient duration for the drink to be emptied from the stomach and absorbed in the intestine. Generally, drinking plain water is better than drinking nothing, but drinking a properly formulated carbohydrate–electrolyte ‘sports’ drink can allow for even better exercise performance. Of importance for rehydration purposes after exercise is consumption of both an adequate volume of fluid (greater than the net deficit of the sweat volume lost) and quantity of sodium. Without both of these, rehydration will be neither rapid nor complete and maintained. There is, however, no good evidence for the inclusion of any other electrolytes. The current generation of commercially available sports drinks are generally formulated to meet the needs of many athletes in many different situations.

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... The water helps the body to compensate for fluid loss through sweat (Carvalho, 2007). Sports drinks consisting of energy sources and electrolytes such as carbohydrates and sodium, respectively, were more effective in enhancing performance compared to water (Ford, 1999;Shirreffs, 2009). Sports drink was often used to compensate for fluid loss, maintain blood glucose levels, rebalance fluid levels, and replenish different enzymes and salts close to the normal level (Shalesh et al., 2014). ...
... Panels commented that the drink was not sweet enough, although they liked the drink overall. The type and concentration of a drink are very dependent on consumers' perceptions (Shirreffs, 2009). Manipulating the sweet taste in fruit drinks could be done through the addition of sweeteners which would affect and suppress the intensity of the sour taste of the fruit. ...
... A sports drink contains water and various nutrients which could be an option for oral rehydration. Sports drink accelerates dehydration, stimulate faster fluid absorption, reduce physiological stress, and promote recovery post-exercise (Shirreffs, 2009). This drink contains carbohydrates, electrolytes, and vitamins and is intended for individuals doing physical activities (Navarro et al., 2016). ...
Article
Prolonged exercise causes excessive fluid loss through sweat which could cause fatigue and reduced performance. Athletes need to restore this fluid loss orally, either from water or carbohydrate-electrolyte drinks. Carbohydrate-electrolyte drinks could be formulated from fruits, such as salak, also known as snake fruit, for instance. This study aimed to develop a sports drink formulated from Sidimpuan salak (Salacca sumatrana (Becc.)) fruit. The formulation of Sidimpuan salak Sports Drink (SSSD) included salak fruit, water, salt and glucose syrup. Salak was blended with a slow juicer to obtain the extract, and mixed with water, salt, and glucose syrup. The SSSD formulation consisted of three formulas, SSSD1, SSSD2, and SSSD3 which differ in the amount of extract added, 250, 200, and 150 mL, respectively. Sensory analysis showed that the panellists enjoyed the sports drink formulation by giving an average rating of 3.4 for colour, 3.4 for aroma, 5.4 for taste and 5.4 for texture. The SSSD1 formulation which was most preferred by the panelists was found to have ash content of 0.33 g/100 mL, total fat of 0.31 g/100 mL, protein of 0.52 g/100 mL, carbohydrate of 13.88 g/100 mL, and total energy of 60.42 g/100 mL. The carbohydrate content and total calories of SDSS1 were significantly different from the other two formulations. From the results obtained, the SSSDs have potential to be developed as a more affordable sports drink, especially among locals.
... In contrast, sports drinks are designed to replace fluid and electrolytes lost via sweat during exercise and provide exogenous carbohydrates (CHO) for oxidation and energy production by muscles and the central nervous system (Baker & Jeukendrup, 2011). Most traditional sports drinks and oral rehydration solutions contain varying concentrations of both CHO and electrolytes, commonly known as carbohydrate-electrolyte solutions (CES) (Shirreffs, 2009). Beverages with different compositions are likely to have varying effects on promoting hydration. ...
... The current consensus, established by the American College of Sports Medicine, is that a CHO-consumption of~30e60 g h À1 is recommended during endurance exercise (Thomas, Erdman, & Burke, 2016). Thus, many leading commercially-available sports beverages contain CHO contents of~6% (Shirreffs, 2009). Additionally, although the hallmark of sports drinks is the improvement in performance via increased CHO-derived substrate availability for energy production in active skeletal muscles, these beverages often also contain various electrolytes to facilitate fluid retention, primarily in the extracellular compartment, and thereby improve hydration status. ...
... The collective findings of these studies suggest that milk and CES promote fluid retention and provides sufficient exogenous CHO to maintain glycogen stores and oxidation rates to a similar degree during prolonged exercise. Further, considering that adding 10 g L À1 glucose to milk did not prolong time-to-exhaustion compared with milk without added glucose (Lee et al., 2008) and that the CHO content of milk is similar to that of most sports beverages (Shirreffs, 2009), it is possible that the CHO content of milk, which typically consists of lactose, which can be hydrolyzed to form glucose and galactose, as opposed to the fructose/sucrose/glucose in most sports drinks, is already optimized for performance. Additional research is necessary to assess the influence of milk consumption versus other sports drinks on exercise performance >1 h, as well as its influence on different measures of exercise capacity other than time-to-exhaustion (i.e., time-trial or sprint-tothe-finish performance). ...
Article
Fluid homeostasis is challenged during exercise when fluid availability is limited or when fluid loss is not properly replaced. Sports drinks are designed to improve hydration by stimulating fluid ingestion, reabsorption, and retention. Milk has been suggested to be an alternative hydration source to sports drinks due to its higher electrolyte concentrations and similar carbohydrate content. As milk has a high energy density and viscosity that may present gastric discomfort, attempts have been made to develop beverages from milk byproducts, such as milk permeate, that may be more efficacious for consumption during exercise. However, there is limited literature on milk permeate-based beverages for hydration or performance purposes. This review aims to identify the properties of milk that promote fluid retention, discuss how milk consumption both during or following exercise may impact performance or rehydration, respectively, and explore the scientific evidence regarding the use of milk permeate for sports drink production.
... The hypothesis is that when the "critical temperature" is achieved, the central nervous system decreases the drive to exercise to reduce heat production and protect against neuronal dysfunction (Judelson et al., 2007). When heat stress is elevated and cardiac output is decreased, blood flow to active skeletal muscles may also be reduced, which could cause reduce nutrient and oxygen delivery required to support aerobic metabolism, as such the intensity of exercise must be decreased (Shirreffs, 2009). ...
... Sports drinks often contain electrolytes and carbohydrates, which enhance the rate of water absorption. Overall, these drinks (including milk) reduce the physiological stress related to exercise and promote recovery following exercise (Roy, 2008;Shirreffs, 2009). Therefore consumption of a sports drink or milk will provide a large amount of water in addition to other components, which could otherwise be obtained from foods and supplements (Kenefick & Cheuvront, 2012;Shirreffs, 2009). ...
... Overall, these drinks (including milk) reduce the physiological stress related to exercise and promote recovery following exercise (Roy, 2008;Shirreffs, 2009). Therefore consumption of a sports drink or milk will provide a large amount of water in addition to other components, which could otherwise be obtained from foods and supplements (Kenefick & Cheuvront, 2012;Shirreffs, 2009). ...
Chapter
Milk and dairy products with their distinct composition of carbohydrates, proteins, fats, and micronutrients are purported to have beneficial effects on human health. They have the potential to enhance exercise performance and recovery and are considered functional sport foods/beverages. This chapter summarizes the current evidence regarding the benefits of dairy products on endurance and resistance exercise, as well as the potential to augment health and performance in a variety of populations including team sport athletes, exercising children and adolescents, and aging adults. The impact of dairy products on weight loss and sleep quality is also discussed.
... The hypothesis is that when the "critical temperature" is achieved, the central nervous system decreases the drive to exercise to reduce heat production and protect against neuronal dysfunction (Judelson et al., 2007). When heat stress is elevated and cardiac output is decreased, blood flow to active skeletal muscles may also be reduced, which could cause reduce nutrient and oxygen delivery required to support aerobic metabolism, as such the intensity of exercise must be decreased (Shirreffs, 2009). ...
... Sports drinks often contain electrolytes and carbohydrates, which enhance the rate of water absorption. Overall, these drinks (including milk) reduce the physiological stress related to exercise and promote recovery following exercise (Roy, 2008;Shirreffs, 2009). Therefore consumption of a sports drink or milk will provide a large amount of water in addition to other components, which could otherwise be obtained from foods and supplements (Kenefick & Cheuvront, 2012;Shirreffs, 2009). ...
... Overall, these drinks (including milk) reduce the physiological stress related to exercise and promote recovery following exercise (Roy, 2008;Shirreffs, 2009). Therefore consumption of a sports drink or milk will provide a large amount of water in addition to other components, which could otherwise be obtained from foods and supplements (Kenefick & Cheuvront, 2012;Shirreffs, 2009). ...
Chapter
Full-text available
Beyond the fact that whey is a by-product of cheese-making, it is used in the manufacture of a great number of foods and food ingredients including, but not limited to, fermented and unfermented beverages, semisolid foods, food supplements, pharmaceutical goods, coatings, and so on. During the last decade, whey and whey components have been increasingly used in the manufacture of whey-based beverages. These whey-based beverages are consumed either plain or supplemented with some nutraceutical components and/or probiotics/prebiotics. Whey beverages supplemented with fruit juice, milk or milk permeate, or nutraceutical compounds are estimated to occupy a larger stake in the dairy and functional foods market in the near future. Heat-triggered sedimentation is the major challenge of whey-based beverage industry. To overcome this handicap and protect the nutritional value of whey beverages, nonthermal food processing technologies may well be considered as alternatives to heat treatment.
... The hypothesis is that when the "critical temperature" is achieved, the central nervous system decreases the drive to exercise to reduce heat production and protect against neuronal dysfunction (Judelson et al., 2007). When heat stress is elevated and cardiac output is decreased, blood flow to active skeletal muscles may also be reduced, which could cause reduce nutrient and oxygen delivery required to support aerobic metabolism, as such the intensity of exercise must be decreased (Shirreffs, 2009). ...
... Sports drinks often contain electrolytes and carbohydrates, which enhance the rate of water absorption. Overall, these drinks (including milk) reduce the physiological stress related to exercise and promote recovery following exercise (Roy, 2008;Shirreffs, 2009). Therefore consumption of a sports drink or milk will provide a large amount of water in addition to other components, which could otherwise be obtained from foods and supplements (Kenefick & Cheuvront, 2012;Shirreffs, 2009). ...
... Overall, these drinks (including milk) reduce the physiological stress related to exercise and promote recovery following exercise (Roy, 2008;Shirreffs, 2009). Therefore consumption of a sports drink or milk will provide a large amount of water in addition to other components, which could otherwise be obtained from foods and supplements (Kenefick & Cheuvront, 2012;Shirreffs, 2009). ...
Chapter
Full-text available
Predictive microbiology aims to evaluate the effect of processing, distribution, and storage operations on microbiological food safety. It is based upon the premise that the response of population of microorganisms to environmental factors are reproducible, and that, by characterizing the environment in terms of identifiable, dominant factors controlling growth responses, it is possible, from past observations, to predict the responses of those microorganisms in other, similar environments. Predictive microbiology models represent the microbial responses to the environment. They are based mainly on observations made in synthetic culture media. Models cannot take into account all factors that may affect the microbial growth but select the most influential factors and only model their effects. The main assumptions of predictive microbiology and risk analysis are discussed in the present chapter. Moreover, the classification of predictive models and application in dairy processing are given. Finally, a case study using the tertiary model Sym’Previus software is presented.
... Spor içecekleri, sıvı kaybını telafi etmek ve karbonhidrat-elektrolit dengesi sağlayarak hidrasyonu artırmak amacıyla geliştirilmiştir. Bu içecekler genellikle karbonhidrat, sodyum, potasyum ve diğer elektrolitlerden oluşan bir formülasyona sahip olmaktadır (Shirreffs, 2009). ...
... Örneğin, Berry ve arkadaşlarının yaptığı çalışmada, süt permeatı bazlı içeceklerin tüketiminden sonra sıvı tutulumu belirgin şekilde artmış ve plazma hacmi genişlemiştir (Berry vd., 2020). Bu durum, özellikle sodyum ve potasyum gibi minerallerin sıvı dengesini düzenlemedeki etkisine atfedilmiştir (Shirreffs, 2009). ...
Article
Egzersiz sırasında sıvı homeostazının korunması, egzersiz kapasitesinin optimize edilmesi için kritik öneme sahiptir. Sıvı kaybı, özellikle sıvı alımının yetersiz olduğu veya emiliminin zorlaştığı durumlarda, hidrasyonu zorlaştırabilir. Spor içecekleri, sıvı alımını, emilimini ve tutulmasını artırarak hidrasyonu iyileştirmek amacıyla tasarlanmıştır. Geleneksel spor içecekleri genellikle karbonhidrat-elektrolit kombinasyonlarına dayanmakta olup, sıvı kaybını telafi etmekte etkilidir. Ancak, süt gibi doğal bileşenler, özellikle yüksek elektrolit konsantrasyonları ve uygun karbonhidrat içeriği nedeniyle sporcu içecekleri için alternatif bir hidrasyon kaynağı olarak önerilmektedir. Bununla birlikte, sütün yüksek enerji yoğunluğu ve viskozitesi, egzersiz sırasında mide rahatsızlıklarına yol açabileceğinden, daha hafif ve sindirimi kolay alternatifler aranmaktadır. Süt permeatı, sütün ultrafiltrasyonu sırasında elde edilen ve karbonhidratlar ile elektrolitler açısından zengin bir yan ürün olup, spor içeceklerine alternatif bir bileşen sunmaktadır. Bu derlemede, süt permeatının hidrasyon üzerindeki potansiyel etkileri ve performansa yönelik katkıları ele alınmaktadır. Literatürdeki mevcut bulgular, süt permeatı bazlı içeceklerin geleneksel karbonhidrat-elektrolit çözeltilerine kıyasla sıvı tutulumu ve rehidrasyon üzerinde olumlu etkiler sağlayabileceğini göstermektedir. Ancak, süt permeatının farklı spor türlerinde ve farklı koşullarda kullanımıyla ilgili veriler sınırlıdır. Bu çalışma, süt permeatının hidrasyon ve performans etkilerini kapsamlı bir şekilde inceleyerek, bu bileşenin spor içecekleri üretiminde nasıl daha verimli kullanılabileceğine dair özgün bir katkı sunmayı hedeflemektedir.
... In particular, according to the Waste Framework Directive (WFD; Directive 2008/98/EC), SCW qualifies as waste unless repurposed as a raw material or ingredient in specific production processes. In this scenario, its handling and disposal are subject to stringent environmental and health regulations, such as Regulation (EC) No. 1069/2009and Regulation (EC) No. 1774/2002. To prevent environmental pollution and disease transmission, direct discharge of SCW into the environment or surface waters is prohibited, and transportation must adhere to waste or organic material transport regulations. ...
... Given the abundant calcium content in SCW, it can serve as a valuable nutritional supplement to address this issue. Additionally, the sodium content in SCW, crucial for hydration, parallels that of sports beverages (Shirreffs 2009;Veniamakis et al. 2022). Overall, SCW emerges as a noteworthy source of essential minerals such as calcium, phosphorus, potassium, sodium, and magnesium, making it a potentially valuable addition to one's diet to address mineral deficiencies and support health and hydration. ...
Article
Full-text available
The second cheese whey (SCW) is the liquid fraction that remains after the production of whey-cheeses. SCW appears as a white to yellow/green opalescent liquid with suspended solids and contains up to 6% lactose and variable amounts of proteins, fats, and mineral salts. Due to its organic load, SCW is characterized by levels of Biochemical Oxygen Demand and Chemical Oxygen Demand that are significantly higher than urban wastewater. Therefore, it poses an environmental challenge and represents a significant cost and a problem for cheese production facilities when it comes to disposal. On the flip side, SCW contains valuable nutrients that make it a cost-effective substrate for bio-based productions including lactose extraction, and the production of lactic acid, bioethanol, eco-friendly bioplastics, biofuels, beverages, bioactive peptides, and microbial starters. A search in Scopus database indicates that despite the numerous potential applications, interest in SCW exploitation is surprisingly limited and, accordingly, sustainable management of SCW disposal remains an unresolved issue. In this review, which marks the first exclusive focus on SCW, with the aim of contributing to increase the interest of both the scientific community and the stakeholders in the exploitation of this by-product, the processes aimed at SCW valorisation will be described, with particular attention to its use in the production of beverages, food and feed, single cell proteins and as a source of biodegradable bioplastics, organic acids and renewable energy. Moreover, to provide valuable insights into its applications and innovations, an overview on patents regarding the exploitation of SCW will be presented. Graphical Abstract
... They can also be preferred as pre-and post-workout drinks. Sports drink can also be defined as a substance consisting of water and other essential micronutrients to help our body recover from stress and meet physiological needs (Shirreffs, 2009). The main purpose of these drinks is to provide the body with carbohydrates and essential minerals to nourish our tissues and organs during activity and to accelerate the overall recovery process during exercise. ...
... In that study, it was noticed that the local mineral water had a Na content of 26 ppm (Lau and Luk, 2002). It was observed that this value was less than other sports drinks sold in the market (Shirreffs, 2009). ...
Article
Full-text available
Dehydration emerges due to lack of fluid balance in the body. In addition, minerals such assodium, potassium, calcium, and magnesium are lost because of dehydration. Athletes losefluids and electrolytes through sweating during exercise, and replacing the lost fluid andelectrolytes is crucial for the continuity of their sports performance. Sports drinks can beconsumed by athletes to replace fluid and electrolytes lost during exercise and to improveperformance. During this period, consumption of sports drinks minimizes dehydration byrestoring the lost mineral and fluid balance. However, the composition of these products,their active ingredients, their effects on sports performance, and their risk factors are mattersof debate. This study was carried out in order to compare sports drinks with the local mineralwater that comes out naturally in the province of Agri. The mineral determinations of thelocal mineral water were made using Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS) instruments. As a result of the analyses, the average sodium (Na) value in the localmineral water was 26.6 ppm, and the magnesium (Mg) average was 7.782 ppm. Nopotassium (K) mineral was detected in Agri local mineral water. Calcium (Ca) mineralaverage was found to be 65.04 ppm, iron (Fe) mineral average 0.0068 ppm, and zinc (Zn)mineral average 0.02457 ppm. Agri natural mineral water contains minerals in similaramounts to sports drinks. Considering these values, it can be a natural alternative to sportsdrinks if potassium mineral and glucose is added to its content, so it can be an alternative tosports drinks
... They can also be preferred as pre-and post-workout drinks. Sports drink can also be defined as a substance consisting of water and other essential micronutrients to help our body recover from stress and meet physiological needs (Shirreffs, 2009). The main purpose of these drinks is to provide the body with carbohydrates and essential minerals to nourish our tissues and organs during activity and to accelerate the overall recovery process during exercise. ...
... In that study, it was noticed that the local mineral water had a Na content of 26 ppm (Lau and Luk, 2002). It was observed that this value was less than other sports drinks sold in the market (Shirreffs, 2009). ...
Article
Full-text available
Dehydration emerges due to lack of fluid balance in the body. In addition, minerals such as sodium, potassium, calcium, and magnesium are lost because of dehydration. Dehydration is commonly seen in athletes during their prolonged and intense exercise periods. Athletes lose fluids and electrolytes through sweating during exercise, and replacing the lost fluid and electrolytes is crucial for the continuity of their sports performance. Sports drinks can be consumed by athletes to replace fluid and electrolytes lost during exercise and to improve performance. During this period, consumption of sports drinks minimizes dehydration by restoring the lost mineral and fluid balance. However, the composition of these products, their active ingredients, their effects on sports performance, and their risk factors are matters of debate. This study was carried out in order to compare sports drinks with the local mineral water that comes out naturally in the province of Agri. The mineral determinations of the local mineral water were made using Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS) instruments. As a result of the analyses, the average sodium (Na) value in the local mineral water was 26.6 ppm, and the magnesium (Mg) average was 7.782 ppm. No potassium (K) mineral was detected in Agri local mineral water. Calcium (Ca) mineral average was found to be 65.04 ppm, iron (Fe) mineral average 0.0068 ppm, and zinc (Zn) mineral average 0.02457 ppm. Agri natural mineral water contains minerals in similar amounts to sports drinks. Considering these values, it can be an alternative to sports drinks.
... In its simplest sense, a sports drink and by inference an energy drink is consumed in association with sport or exerciseeither in preparation for exercise, during exercise itself or as a recovery drink after exercise. By definition, a drink is a liquid substance and as such, water is a main ingredient [76]. ...
... However, it is important at this point to also delineate the difference between sport drinks and energy drinks. The majority of mainstream sports drinks have a carbohydrate content close to 6% weight/ volume and contain small amounts of electrolytes, the main one being sodium [76]. While, in the United States the Food and Drug Administration [77] defines energy drinks (EDs) as "a class of products in liquid form that typically contains caffeine, with or without other added ingredients." ...
... Dehydration by losing more than 2% of body weight may impair endurance performances even during relatively short games such as taekwondo [5,8]. The effect of rehydration with different types of fluid intake such as water or sport drinks on performance has been widely investigated among athletes [9][10][11][12][13][14][15]. However, few studies have inves-tigated the effect of rehydration with mineral water such as Zamzam water on the hydration status of athletes. ...
... To our knowledge, the impact of rehydration with Zamzam water on fitness components such as cardiorespiratory fitness as one of the main fitness components has yet to be investigated. Zamzam water has unique characteristics compared to normal water, including being rich in minerals [12], and being an alkaline fluid (average pH = 8) [15]. Therefore, Zamzam water with its characterestics may help to maintain wholebody fluid homeostasis [16]. ...
Article
Full-text available
Background: The aim of the present study was to examine the effect of rehydration with mineral water on cardiorespiratory fitness in athletes. Methods: Twenty athletes (age 21.7 ± 3 years) underwent a random, crossover-design experimental trial. Three visits were arranged, with the first for baseline measurement. The second visit included three phases (pre-dehydration, post-dehydration, and post-rehydration), with either Zamzam (mineral water) or bottled water (control water) used. The third visit was similar to the second visit, but with an exchange of the type of water used. Cardiorespiratory fitness and blood parameters were evaluated. Results were compared between Zamzam water and bottled water, and between the phases for each type of water. Results: No significant difference was found between Zamzam and bottled water for the cardiorespiratory fitness markers. However, Zamzam water maintained cardiorespiratory functions including VO 2peak, VT1, VT2, and VE peak, even with rehydration equivalent to 100% of the loss in body weight following exercise-induced dehydration (>2% loss in body weight). Rehydration with bottled water was associated with a significant reduction in both the VO 2peak and VE peak. Conclusions: Rehydration with mineral water such as Zamzam is unlikely to impair cardiorespiratory fitness, even with an intake equal to 100% of the loss in body weight.
... Perceptions that sports drinks provide health benefits like hydration, athletic performance, and athletic recovery are reinforced by sports drink advertisements (Shirreffs, 2009). Athletic activity is also featured in energy drink advertising, but while sports drink ads tend to showcase mainstream sports such as football and basketball, energy drink ads tend to include extreme sports such as BMX, car racing, and snowboarding . ...
... The proposed importance of athletic identity is due to the fact that advertising messages for both sports and energy drinks commonly associate the products with sports participation, athletic performance, and hydration (Bragg et al., 2018;Folta et al., 2006;Jenkin et al., 2014;Shirreffs, 2009). If athletic identity does moderate the relationship between ad exposure and product consumption, it would indicate that adolescents are both likely to allocate resources to messages relevant to athletic identity and also are accepting of advertisement claims that these products are helpful for athletes, particularly among those who are athletes themselves. ...
Article
Understanding why sports and energy drinks remain increasingly popular among adolescents despite declines in other sugar sweetened beverages is critical. This study points to memory for advertising exposure and adolescent athletic identity as two aspects that together help to explain consumption. An online survey of U.S. adolescents aged 14-18 (n = 503) was combined with Nielsen data for television and social media advertising expenditures by sports and energy drink brands in participants' designated market areas (DMAs). Advertisement recall mediates the relationship between social media DMA expenditures and sports and energy drink consumption. Recall for television advertisements is related to consumption but is unrelated to television DMA expenditures. Athletic identity moderated the relationship between recall and consumption such that consumption increased as both recall and athletic identity increased, suggesting a role for motivated memory and motivated processing of ad messages based on athletic identity consistent with the limited capacity model of motivated media message processing. Based on these results, we conclude that effectiveness of expenditures in influencing behavior is dependent upon both ad recall and ad relevance, and that athletic identity is an important factor in ad effectiveness in the context of sports and energy drinks advertising.
... In this context, we recently reported that ingestion of an isomaltulose beverage under an exercise-induced dehydrated state was associated with a better net fluid retention, and therefore fluid balance as compared to sucrose [16]. Notably, this response occurred even for an isomaltulose concentration of 6.5%, which is a typical carbohydrate content of many commercial sports drinks [17]. However, it is unclear if the consumption of an isomaltulose beverage under a resting euhydrated state can mediate a reduction in urine output and thus elevate BHI as compared to other carbohydrate-electrolyte beverages. ...
... During the experimental session (see below), the participants consumed either a carbohydrate-electrolyte beverage consisting of 6.5 g per 100 ml solutions of isomaltulose (ISO), a carbohydrate-electrolyte beverage consisting of 6.5 g per 100 ml solutions of sucrose (SUC), or plain water (Control). For both carbohydrate-electrolyte beverage, the carbohydrate and electrolyte concentrations are equivalent to the content of most commercial sports beverages [17]. A list of nutrients contained in each beverage is presented in Table 1. ...
Article
Isomaltulose is a low glycemic and insulinaemic carbohydrate now used as an alternative sweetener in beverages. However, it remains unclear if hydration status may be impacted differently with the consumption of beverages containing isomaltulose as compared to sucrose, a common beverage sweetener. Thirteen young adults (7 women) consumed 1L of a carbohydrate beverage (with low electrolyte content) containing either 6.5%-sucrose, 6.5%-isomaltulose, or water within a 15-min period. For each beverage, beverage hydration index (BHI, a composite measure of fluid balance after consuming a test beverage relative to water) was calculated from urine volume produced over a 3-hour period following ingestion of the carbohydrate beverages relative to water. The change in plasma volume (ΔPV), blood glucose, and lactate concentrations were assessed every 30-min post-beverage consumption. Isomaltulose ingestion attenuated urine production as compared to water and sucrose (P≤0.005) over the 3-hour post-ingestion period. However, no differences were observed between sucrose and water (P=0.055). BHI was 1.53±0.44 for isomaltulose (P≤0.022 vs. sucrose and water) and 1.20±0.29 for sucrose (P=0.210 vs. water). A transient reduction in ΔPV was observed following the ingestion of the isomaltulose beverage (at 30-min, P=0.007 vs. sucrose). Thereafter, no differences in ΔPV between beverages were measured. Increases in blood glucose and lactate, indices of absorption and utility of glucose, were delayed in the isomaltulose as compared to sucrose beverage. In summary, we demonstrated a greater BHI with a carbohydrate-electrolyte beverage containing isomaltulose as compared to sucrose. This may in part be attributed to a delayed absorption of isomaltulose reducing diuresis. (250/250).
... Habitual caffeine and alcohol consumers were therefore excluded to avoid the negative impact of withdrawal effects on the exercise performance and the study. For optimal performance of exercise and to control for the hydration status, participants were instructed to take in food and water about 3 h before coming to the gym (Shirreffs, 2009). Additionally, each of them was given 500 ml of water to be drunk, upon entry into the gym, all at once an hour before the exercise (Shirreffs, 2009). ...
... For optimal performance of exercise and to control for the hydration status, participants were instructed to take in food and water about 3 h before coming to the gym (Shirreffs, 2009). Additionally, each of them was given 500 ml of water to be drunk, upon entry into the gym, all at once an hour before the exercise (Shirreffs, 2009). In controlling for diurnal variations, all participants underwent the training session from 4 to 6 p.m. Baseline ocular measurements were taken after a 30-min sitting in the gym. ...
Article
The study investigated the differential response to a single bout of maximal incremental treadmill exercise between athletes and non-athletes without dry eyes regarding tear secretion, tear film stability, visual acuity (VA), and stereoacuity. Additionally, the study examined the effect of gender and the duration of exercise on exercise-induced changes. Study participants included young university students aged 18–25 years who were athletes (male/female: 13/13) or non-athletes (male/female: 17/9). Participants underwent an aerobic exercise session using a treadmill and following the laid down Bruce treadmill test protocol till exhaustion. Measurements were taken in the order of distance VA, stereopsis, non-invasive tear break-up time (TBUT), and phenol red thread test, at baseline and after the exercise regimen. Within- and between-subject analyses using multiple t-tests with correction for multiple comparisons were performed to determine differences before and after exercise in athletes and non-athletes. Subsequently, ANCOVA was used to assess the influence of gender and the duration of exercise. The mean age (SD) of the athletes and the non-athletes was 22.4 ± 2.1 years and 21.8 ± 2.1 years, respectively (p = 0.357). Before exercise, the athletes had higher TBUT than non-athletes (14.6 ± 2.9 seconds vs. 11.9 ± 3.8 seconds; p = 0.021), but no difference was observed in any other ocular measurements. After exercise, the athletes showed significant improvement in tear secretion with the basal tear secretion increasing from 22.3 ± 2.5 mm to 25.8 ± 1.7 mm (p < 0.001). The non-athletes on the other hand had a borderline increase in tear secretion from 21.42 ± 2.85 mm to 23.73 ± 2.68 mm (p = 0.08). Also, the TBUT was much improved in the athletes after exercise compared to the non-athletes (17.7 ± 2.7 seconds vs. 14.8 ± 2.9 seconds, p = 0.004). Additionally, exercise improved the VA indifferently between the groups, while stereoacuity was unchanged after exercise in either group. Gender had no influence on the differences in the tear function measures between athletes and non-athletes after exercise. The duration of exercise, however, showed a borderline effect on the tear film stability (p = 0.068) after exercise. Our findings support the differential effect of maximal incremental treadmill exercise on tear secretion and tear film stability between athletes and non-athletes. Thus, increased physical fitness and the duration of exercise might be crucial in the improvement of tear function through aerobic exercise.
... 22 The excessive intake of fructose, corn syrup, and other substances found in soda cause an increased risk of gastrointestinal disturbance, delay gastric emptying, and reduces fluid absorption, secreting water into the intestine, increasing the chances of dehydration. 24,26 Nutrition Knowledge. Results suggest that these teams are aware of many items and correct information assessed by the questionnaire. ...
... Studies have correlated this meal with improved cognition and academic performance, as nutrition gives the brain proper building blocks to create and maintain connections. 26,27 Previous studies have reported the deleterious effects of weight cycling and rapid weight loss in weight class sports on mental status. 28,29 Taking breakfast regularly also significantly improves performance among athletes by returning glycogen in the liver and muscle after the overnight fast. ...
Article
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Objectives: The study aims to assess the dietary habits and nutritional knowledge of selected Philippine national combat sports athletes and determine the correlation of demographics and sources of nutrition information with participants’ dietary habits and nutrition knowledge. Methods: This cross-sectional study included assessing boxing and taekwondo Philippine national athletes using the Dietary Habits and Nutrition Knowledge Questionnaire: Filipino Version. Data were analyzed using descriptive statistics and inferential statistics between sports comparison and exploratory correlation and regression analyses. Alpha was set at 0.05. Results: A total of 44 participants aged 21+ 3.4 years were able to participate in the study. Responses revealed that 69.44% have fair dietary habits and 73.54% have good nutritional knowledge. Results indicated no significant difference between the two sports in dietary habits and nutritional knowledge (p>0.05). Further analyses revealed that years in playing (r= 0.32, p= 0.04), and sources of nutrition information, precisely strength and conditioning coach (r= 0.36, p= 0.02), and peers (r= 0.39, p= 0.01) have a significant correlation with good dietary habit and nutritional knowledge, respectively. Conclusion: Overall, Filipino national athletes of boxing and taekwondo have fair dietary habits and sound nutritional knowledge. Furthermore, nutritional knowledge sources are possible relevant factors that may affect the dietary habits and nutritional knowledge of combat sports athletes.
... Tujuan minum air dingin adalah untuk mempercepat rehidrasi, mempercepat penyerapan cairan, menghilangkan stres fisiologis, dan mempercepat pemulihan energi setelah kelelahan (Shirreffs, 2013). Saat minum air, tubuh melepaskan histamin, gatrine, dan serotonin. ...
Book
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Buku Panduan Lengkap Untuk Tenaga Kesehatan: Pencegahan, Pengobatan, dan Perawatan Komprehensif Pasien Dengan Kanker ini menyajikan pemahaman yang komprehensif tentang kanker dari berbagai sudut pandang. Ditulis oleh para ahli di bidangnya, buku ini membahas segala hal mulai dari penyebab kanker, pencegahan, perawatan hingga pengobatan terkini. Buku ini mengupas tuntas apa itu kanker, bagaimana sel-sel normal berubah menjadi ganas, dan faktor-faktor yang memicu pertumbuhan sel kanker. Selain itu juga berfokus pada pencegahan kanker, mulai dari pentingnya gaya hidup sehat hingga peran vaksinasi. Terdapat bab yang membahas berbagai metode pengobatan kanker yang ada saat ini, seperti kemoterapi, radioterapi, dan imunoterapi, menyoroti pentingnya perawatan pasien kanker secara holistik, tidak hanya fisik, tetapi juga mental dan sosial. Terakhir, memberikan gambaran tentang masa depan pengobatan kanker, termasuk perkembangan teknologi terbaru dan tantangan yang masih dihadapi. Mengapa Buku Ini Penting? Buku ini memberikan informasi yang akurat dan mudah dipahami tentang kanker. Baik bagi pasien, keluarga, tenaga kesehatan, maupun masyarakat umum, buku ini dapat menjadi panduan yang berharga. Dengan membaca buku ini, pembaca akan lebih memahami penyakit kanker, mengetahui upaya pencegahan yang efektif, dan mendapatkan harapan baru dalam pengobatan. Keunggulan Buku Ini: • Karya kolektif para ahli di berbagai bidang. • Informasi yang akurat dan up-to-date. • Bahasa yang mudah dipahami. • Pendekatan yang komprehensif. Buku “Panduan Lengkap Untuk Tenaga Kesehatan: Pencegahan, Pengobatan, dan Perawatan Komprehensif Pasien Dengan Kanker” adalah buku yang sangat relevan bagi para tenaga kesehatan maupun masysrakat awam yang ingin mengetahui lebih banyak tentang kanker. Dengan membaca buku ini, Anda akan lebih siap menghadapi tantangan penyakit ini dan mengambil langkah-langkah yang tepat untuk memberikan pelayanan yang paripurna pada pasien dengan kanker.
... In the recreational sports setting, consumers anticipate high water demand and therefore may choose to save money by drinking tap water. Conversely, they might consider it wiser to purchase a different beverage altogether, such as an isotonic sports drink, which promises a better hydration than water (Shirreffs, 2009). ...
Article
European water policies aim to promote tap water consumption among citizens. Our survey of 5815 German respondents investigates factors influencing tap water consumption in key out-of-home settings: workplace, recreational sports, hospitality and travel. Results show tap water is consumed most frequently in sports settings and least in hospitality, highlighting the importance of situational factors over price. Strong correlations between at-home and out-of-home drinking water choices suggest stable preferences and habit effects. Policy interventions should focus on encouraging tap water consumption at home, offering carbonation options out-of-home, and shifting norms and industry discourse in hospitality settings.
... Certain minerals, including calcium (Ca), potassium (K), magnesium (Mg), sodium (Na), and phosphorus (P) are found in cells and tissues in significant amounts. There are trace elements such as iron (Fe), manganese (Mn), selenium (Se), and zinc (Zn) that are present in smaller quantities but play vital roles in various biological processes (Shirreffs, 2009). The primary discoveries of our study pertain to the comparative levels of Na (265-275 mg/L) and K (856-1010 mg/L) in the prepared drinks. ...
Article
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This study explores the formulation and evaluation of a novel isotonic sports drink using dates of Ajwa variety (Phoenix dactylifera L.) as a natural alternative to synthetic ingredients commonly found in commercially available sports beverages. Ajwa dates were selected for their rich bioactive components, including natural sugars, phenolic compounds, and essential minerals, which align with the functional requirements of isotonic drinks. Three formulations (ASD1, ASD2, ASD3) were developed by varying the ratio of Ajwa date pulp to deionized water, and these formulations were evaluated for their physicochemical properties, mineral content, antioxidant capacity, microbiological safety, and sensory acceptance. The ASD2 (25 % pulp) emerged as the most promising, with the highest sensory scores (8.2/9 in overall acceptability). ASD2 demonstrated excellent phys-icochemical stability over a 90-day storage period, maintaining an osmolality of 297 ± 3.17 mOsm/kg, suitable for rapid hydration. The formulation achieved an optimal pH of 4.62 ± 0.12 and provided 34.01 ± 0.47 kcal/ 100 g energy, sufficient for replenishing energy during physical activity. Microbiological tests confirmed the safety, with minimal total plate count (1 cfu/mL) and no detected coliforms or molds. Notably, the drink retained its antioxidant capacity, with ascorbic acid levels around 1 mg/100 mL and phenolic content ranging between 2.5 and 3.0 g/kg gallic acid equivalent. The study concludes that the Ajwa date isotonic sports drink is a promising natural alternative for athletes, offering both hydration and additional health benefits. This research highlights the potential for using natural ingredients in sports nutrition and provides a foundation for future studies on the commercialization of such products.
... Certain minerals, including calcium (Ca), potassium (K), magnesium (Mg), sodium (Na), and phosphorus (P) are found in cells and tissues in significant amounts. There are trace elements such as iron (Fe), manganese (Mn), selenium (Se), and zinc (Zn) that are present in smaller quantities but play vital roles in various biological processes (Shirreffs, 2009). The primary discoveries of our study pertain to the comparative levels of Na (265-275 mg/L) and K (856-1010 mg/L) in the prepared drinks. ...
Article
Full-text available
1 Highlights • Developed an isotonic sports drink with Ajwa dates as a natural alternative. • Assessed the physicochemical and microbiological properties of three formulations. • The ASD2 formulation (25% Ajwa pulp) showed best sensory qualities. • ASD2 (25% Ajwa pulp) had the best sensory attributes and stayed stable for 90-days. • The study highlighted the Ajwa dates' potential in sports nutrition. Abstract: This study explores the formulation and evaluation of a novel isotonic sports drink using dates of Ajwa variety (Phoenix dactylifera L.) as a natural alternative to synthetic ingredients commonly found in commercially available sports beverages. Ajwa dates were selected for their rich bioactive components, including natural sugars, phenolic compounds, and essential minerals, which align with the functional requirements of isotonic drinks. Three formulations (ASD1, ASD2, ASD3) were developed by varying the ratio of Ajwa date pulp to deionized water, and these formulations were evaluated for their physicochemical properties, mineral content, antioxidant capacity, microbiological safety, and sensory acceptance. The ASD2 (25% pulp) emerged as the most promising, with the highest sensory scores (8.2/9 in overall acceptability). ASD2 demonstrated excellent physicochemical stability over a 90-day storage period, maintaining an osmolality of 297±3.17 mOsm/kg, suitable for rapid hydration. The formulation achieved an optimal pH of 4.62±0.12 and provided 34.01±0.47 kcal/100 g energy, sufficient for replenishing energy during physical activity. Microbiological tests confirmed the safety, with minimal total plate count (1 cfu/mL) and no detected coliforms or molds. Notably, the drink retained its antioxidant capacity, with ascorbic acid levels around 1 mg/100 mL and phenolic content ranging between 2.5-3.0 g/kg gallic acid equivalent. The study concludes that the Ajwa date isotonic sports drink is a promising natural alternative for athletes, offering both hydration and additional health benefits. This research highlights the potential for using natural ingredients in sports nutrition and provides a foundation for future studies on the commercialization of such products.
... These drinks can enhance athletic performance in the short term (117, 118). There must be a balance between the amount of beverages consumed and the net volume of sweat lost in order to make allowance for ongoing obligatory urine loss (118). Table 1 shows two studies on the effect of consuming caffeinated energy drink on the athletic performance of 16-year-old youth. ...
Article
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Information regarding the dietary requirements and consumption of young athletes is limited. Hence, the aim of this narrative review is to provide a comprehensive combination of research and review papers on the nutritional status of young athletes aged 5–18 years old, as well as quantitative, qualitative, wholesome foods, food choices, and eating disordered data concerning the dietary requirements for growing young athletes. This study involved systematic searches of electronic databases, including Google Scholar, PubMed, Science Direct, Scopus, and Web of Science. The specific criteria for identifying research papers published in English from July 1980 until May 2024 were included. Only 48 studies out of 1,262 were included in this narrative review. The findings of this study suggest that, compared with adults, junior athletes need a unique approach to meet their dietary needs. Growth, development, and general athletic performance depend on macronutrients, as they are vital nutrients for young active athletes. However, research on enhancing junior athletes’ performance is still in progress, and studies on hydration status, and eating disorders are limited.
... While salt is used in the production of ricotta, scotta only delivers about 147 mg of Na, about 6% of the DV. Na is important for hydration [39], and its level in scotta is similar to that of sports beverages [40]. ...
Article
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Scotta is an underutilized whey by-product of ricotta making. In this study, we investigated the utilization of scotta in beer production. To understand the quality of regional scotta, samples from eight Sicilian ricotta makers were analyzed for pH, total protein, fat, lactose, titratable acidity, % salt, total plate count, lactic acid bacteria counts, and minerals. Overall, the samples had low amounts of residual protein and fat. The average lactose content was 4.81 g/100 mL ± 0.52 g, with a pH of 6.12 ± 0.17 and a salt content of 1.05% ± 0.24. The majority of lactic acid bacteria counts were below the limit of detection. The total plate counts were more variable, ranging between 102 to 103 CFU/mL, suggesting occasional post-processing contamination during handling. Scotta was then used to replace some of the water and sugar in the production of two beer styles: (i) a Gose, a salty and acidified German beer style, and (ii) a sweet milk stout. A trained panel used for sensory analysis found that these prototypes fit within the sensory profiles of commercial beers of these styles. This work highlights opportunities to upcycle dairy by-products into novel fermented beverages that would be appealing to consumers.
... Consequently, several research studies have been undertaken to ascertain the expeditious replenishment of fluid loss subsequent to dehydration. The available evidence indicates that sports drinks that include CHO and electrolytes are generally more effective for rehydration purposes compared to plain water [29,30]. Nevertheless, recent research has shown that the use of protein-containing solutions for rehydration is more effective in preserving fluid balance compared to the ingestion of sports drinks [13,[16][17][18]. ...
Article
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Protein ingestion is known to enhance post-exercise hydration. Whether the type of protein (i.e., whey, casein) can alter this response is unknown. Accordingly, this study aimed to compare the effects of the addition of milk-derived whey isolate or casein protein to carbohydrate-electrolyte (CE) drinks on post-exercise rehydration and endurance capacity. Thirty male soldiers (age: 24 ± 2.1 y; VO 2max : 49.3 ± 4.7 mL/kg/min) were recruited. Upon losing~2.2% of body mass by running in warm and humid conditions (32.3 • C, 76% relative humidity [RH]), participants ingested either a CE solution (66 g/L carbohydrate [CHO]), or CE plus isolate whey protein (CEW, 44 g/L CHO, 22 g/L isolate whey), or CE plus isolate casein protein (CEC, 44 g/L CHO, 22 g/L isolate casein) beverage in a volume equal to 150% of body mass loss. At the end of the 3 h rehydration period, a positive fluid balance was higher with CEW (0.22 L) compared to CEC (0.19 L) and CE (0.12 L). Overall mean fluid retention was higher in CEW (80.35%) compared with the CE (76.67%) and CEC trials (78.65%). The time of the endurance capacity test [Cooper 2.4 km (1.5 miles) run test] was significantly higher in CEC (14.25 ± 1.58 min) and CE [(12.90 ± 1.01 min; (p = 0.035)] than in CEW [(11.40 ± 1.41 min); (p = 0.001)]. The findings of this study indicate that the inclusion of isolate whey protein in a CE solution yields superior outcomes in terms of rehydration and enhanced endurance capacity, as compared to consuming the CE solution alone or in conjunction with isolate casein protein.
... However, not everyone can drink when they want and as much water as they want. For example, the availability of fluids during intense exercise can be restricted, and one can feel thirst but not be able to drink (Orrù et al., 2018;Shirreffs, 2009). ...
Article
Full-text available
The sensation of thirstiness is the desire to drink water. In certain situations, the ingestion of liquid water can be restricted. As a result, thirstiness is not relieved, resulting in an uncomfortable and distressing situation. The present review describes thirstiness and hydration, the food products and beverages that cause thirstiness, and the beverages and food products currently available to quench thirstiness in individuals with restricted access to liquid ingestion. It also discusses how to measure the effectiveness of calming thirstiness. To diminish thirstiness distress, different alternatives to liquids are proposed. Individuals with swallowing disorders are given thickened water, individuals with restricted water ingestion are given ice cubes or ice popsicles of different flavors, and sportspeople are given energy gels. However, current beverage solutions seem not to relieve thirst fully, although some stimuli like iced water, flavors (especially lemon and mint), or acids seem to work better than plain stimuli and could be added to existing products. Therefore, there is still a need to incorporate these strategies into beverage and food formulations and to test their effectiveness.
... Teteven Municipality is in Stara Planina with mountainous climate and water [44]. For hydration of human body it is important not only the amount of water intake [45], but the quality of water is essential [6] for health and recovery [46][47][48]. ...
Article
In Bulgaria there are the following mountains – Stara Planina (Balkan), Rila, Pirin, Rodope etc. The name of the Balkan Peninsula is from the old name of the mountain Stara Planina – Balkan. In Bulagria there are 139 peaks more than 2000 m above sea level. The biggest peak in Balkan Peninsula is Mousala (2925 m). Teteven municipally has big part of Stara planina mountain with the highest peak Vezhen (2198 m). The event “Days of mountain water” is one of a kind in Bulgaria. It takes place on 11th June and lasts for several days in the Municipality of Teteven, Bulgaria. Its beginning dates from 2010, and it is a joint undertaking between Ignat Ignatov, Scientific Research Center of Medical Biophysics and Municipality of Teteven, Bulgaria. The event is connected with research of microbiological and physicochemical parameters of mountain spring waters from Municipality of Teteven, Bulgaria. The applied spectral method is „NES“. The analyses show the optimum quantity among the minerals of Calcium (Са2+), Magnesium (Mg2+), Potassium (K+), Sodium (Nа+), Manganese (Mn2+) and Zinc (Zn2+) that provide the right balance in the human body for health and longevity. Considered is the history of the event and what is achieved by the organizers. The emphasis is on the main objectives set out by the event, and the accomplished tasks for its successful delivering. Representatives of 15 states have participated in it – Bulgaria, Austria, Germany, Switzerland, Russia, USA, France, Israel, Czech Republic, Denmark, Turkey, Greece, Hungary and Serbia. A survey was conducted regarding the event “Days of mountain water” in the Facebook group “Teteven Balkan”. 66 people responded on a random basis. The aim of the survey was the people to estimate how useful stay in Teteven municipality is. In the present article are listed in more detail the natural assets of municipal area of Teteven, located in “Fore-Balkan” in the central part of Stara planina Balkan range. The possibilities are shown for development of tourism in the region, its particular characteristics and specific features. Analyzed are the water resources, the mountain water as a factor for health and longevity. The information helps for development of tourism in the region. Described are the springs and fountains of mountain water in Teteven and its surrounding municipal areas. It is conducted quantitative and qualitative analysis of the chemical and physical parameters of the springs. On six of the springs are placed information signs about the chemical composition, physical parameters and properties relating to health.
... Moreover, PRO would slow down tiredness and improve muscle function as protein-based drink provides the body with fuel for tissue repair and building whereas electrolytes would restore salts lost in sweat, and promote water and CHO assimilation. Blood electrolytes such as potassium, sodium, chloride and bicarbonate also help in regulating nerve and muscle function, as well as maintain acid-base balance and water (Orrù et al., 2018;Shirreffs, 2009). This strategy would allow for enhancing performance as well as reducing heat stroke related complications for soldiers ...
... Because of these inconveniences, the food sector has decided to develop a range of products with high electrolyte content to meet nutritional needs. Nowadays, most sports drinks on the market contain sodium, chloride, and potassium ions, because during physical exertion, there is an increased loss of these minerals [56]. ...
Article
Full-text available
Underlying the dawn of humanity was primarily the search for food and access to drinking water. Over the course of civilization, there has been a significant increase in drinking water quality. By the average of the nutritional standards, the daily water demand is 2.5 L (also including liquid products such as tea, coffee, or soup). However, it is worth noticing that the need is strictly individual for each person and depends on two major factors, namely, epidemiological (sex, age state of health, lifestyle, and diet) and environmental (humidity and air temperature). Currently, our diet is more and more often enriched with isotonic drinks, functional drinks, or drinks bearing the hallmarks of health-promoting products. As a result, manufacturing companies compete to present more interesting beverages with complex compositions. This article will discuss both the composition of functional beverages and their impact on health.
... Yeterli sıvı alınması durumunda, egzersiz başlangıcında vücutta, sıvı miktarı denge durumundadır. Antrenman esnasında ise yoğun terlemeye bağlı olarak bu denge bozulur (Wilmore ve Costill, 2004;Shirreffs, 2009). Sporcular kaybettikleri sıvıyı yeterli miktarda sıvı alarak yerine koymalıdırlar. ...
Article
Full-text available
Bu araştırma bilek güreşi sporcularının antrenman ve müsabaka dönemi beslenme alışkanlıkları ve ergojenik yardımcı kullanımlarının incelenmesi amacıyla yapılmıştır. Çalışmaya aktif olarak ortalama 4 yıldır bilek güreşi yapan 215 lisanslı sporcu gönüllü olarak katılmıştır. Çalışma nicel araştırma yöntemlerinden tarama modeline göre tasarlanmıştır. Katılımcılar basit tesadüfi örnekleme yöntemine göre belirlenmiştir. Çalışmada veriler “Google Forms” aracılığı ile toplanmıştır. Elde edilen verilere Microsoft Excel programı aracılığıyla frekans ve yüzde analizi yapılmıştır. Analiz sonuçlarına göre katılımcıların antrenman ve müsabaka döneminde benzer beslenme alışkanlıkları sergilediği tespit edilmiştir. Ayrıca katılımcıların büyük bir bölümünün ergojenik yardımcıları kullanmadığı da çalışmanın bir diğer sonucudur.
... Kad se dodatak koristi za uspješno postizanje fizioloških, odnosno prehrambenih ciljeva koji se javljaju u sportu, može poboljšati sportske performanse (Burke i Read, 1993). Jedni od široko rasprostranjenih i lako dostupnih suplemenata upravo su sportski napitci koji su po svom sastavu tekuća mješavina ugljikohidrata i elektrolita, a koriste se u svrhu zamjene za tekućinu, punjenja ugljikohidratima i nutritivnih dodataka (Smith, 1992;Shirreffs, 2009). Dokazano je da tijekom vježbi snage i izdržljivosti odgovarajući unos sportskog napitka za očuvanje hidratacije i opskrbu dodatnim ugljikohidratnim supstratom, za mišiće koji iscrpljuju glikogen, poboljšava radnu snagu (Burke i Read, 1993). ...
Article
Cilj provedenog istraživanja bio je provjeriti postoji li razlika kod pojedinaca koji koriste i ne koriste sportske dodatke prehrani u aspektima zadovoljenja potreba vlastitog tijela i stajališta oko toga je li ih vaganje deprimira, smatraju li da imaju lijepo tijelo i svjesnosti o vlastitom tjelesnom izgledu. Također, studija je imala za cilj provjeriti i postojanje razlike između osoba koje se bave i koje se ne bave fitnesom u domenama zadovoljstva raspoloženjem i odnosa s drugim ljudima. U istraživanju su sudjelovale osobe u dobnom rasponu od 18 do 56 godina, od toga 141 muškarac i 552 žene. Rezultati su pokazali kako osobe koje koriste suplemente više brinu o zadovoljavanju potreba vlastitog tijela, imaju izraženiji stav da ih vaganje deprimira, izraženije mišljenje da imaju lijepo tijelo te veću svjesnost o vlastitom izgledu nego osobe koje ne koriste suplemente. Nadalje, osobe koje se bave tjelesnom aktivnošću zadovoljnije su svojim raspoloženjem od osoba koje se ne bave tjelesnom aktivnošću. S druge strane, nije pronađena razlika između osoba koje se bave i osoba koje se ne bave tjelesnom aktivnošću u zadovoljstvu odnosa s drugim ljudima.
... Kad se dodatak koristi za uspješno postizanje fizioloških, odnosno prehrambenih ciljeva koji se javljaju u sportu, može poboljšati sportske performanse (Burke i Read, 1993). Jedni od široko rasprostranjenih i lako dostupnih suplemenata upravo su sportski napitci koji su po svom sastavu tekuća mješavina ugljikohidrata i elektrolita, a koriste se u svrhu zamjene za tekućinu, punjenja ugljikohidratima i nutritivnih dodataka (Smith, 1992;Shirreffs, 2009). Dokazano je da tijekom vježbi snage i izdržljivosti odgovarajući unos sportskog napitka za očuvanje hidratacije i opskrbu dodatnim ugljikohidratnim supstratom, za mišiće koji iscrpljuju glikogen, poboljšava radnu snagu (Burke i Read, 1993). ...
Article
Full-text available
Cilj provedenog istraživanja bio je provjeriti postoji li razlika kod pojedinaca koji koriste i ne koriste sportske dodatke prehrani u aspektima zadovoljenja potreba vlastitog tijela i stajališta oko toga je li ih vaganje deprimira, smatraju li da imaju lijepo tijelo i svjesnosti o vlastitom tjelesnom izgledu. Također, studija je imala za cilj provjeriti i postojanje razlike između osoba koje se bave i koje se ne bave fitnesom u domenama zadovoljstva raspoloženjem i odnosa s drugim ljudima. U istraživanju su sudjelovale osobe u dobnom rasponu od 18 do 56 godina, od toga 141 muškarac i 552 žene. Rezultati su pokazali kako osobe koje koriste suplemente više brinu o zadovoljavanju potreba vlastitog tijela, imaju izraženiji stav da ih vaganje deprimira, izraženije mišljenje da imaju lijepo tijelo te veću svjesnost o vlastitom izgledu nego osobe koje ne koriste suplemente. Nadalje, osobe koje se bave tjelesnom aktivnošću zadovoljnije su svojim raspoloženjem od osoba koje se ne bave tjelesnom aktivnošću. S druge strane, nije pronađena razlika između osoba koje se bave i osoba koje se ne bave tjelesnom aktivnošću u zadovoljstvu odnosa s drugim ljudima.
... During the experimental session (see details below), the participants consumed either a 1L beverage containing electrolytes and either isomaltulose (ISO) or sucrose (SUC) carbohydrates in the amount of 6.5 g per 100 ml of solution. This carbohydrate concentration is commonly found in most commercial sports drinks (Shirreffs 2009). A list of nutrients contained in each beverage is presented in Table 1. ...
Article
Full-text available
Purpose Isomaltulose is a low glycemic and insulinaemic carbohydrate increasingly used as an alternative sweetener in commercial beverages. While isomaltulose beverages can improve hydration status compared to sucrose-based beverages, it remains unclear if ingestion of an isomaltulose beverage prior to exercise in the heat may improve plasma volume (PV) and thermoregulatory responses. Methods Twelve endurance-trained men consumed a 1L carbohydrate beverage containing either 6.5%-sucrose (SUC) or 6.5%-isomaltulose (ISO) 60 min prior to 5 successive, 15-min bouts of moderate-intensity (60% of their pre-determined maximum oxygen uptake) in the heat (32 °C, 50% relative humidity), each separated by a 5 min rest. A 6th bout was performed, wherein the participant adjusted running speed to maximize distance covered within the 15-min period. The change (Δ) in PV, heart rate (HR), body core (rectal and gastrointestinal) and skin temperatures, and whole-body sweat loss were assessed during each exercise bout. Results Ingestion of ISO induced a higher ΔPV at 4th bout only (P < 0.001) and lower HR (P = 0.032, main effect of beverage) during exercise compared to those of SUC. Body core and skin temperatures and whole-body sweat loss did not differ between conditions (all P ≥ 0.192, interaction effect). Running distance covered in final exercise bout tended to increase (~ 5%) in ISO versus SUC (P = 0.057, d = 0.64). Conclusions Relative to a sucrose-based beverage, ISO ingestion prior to exercise in the heat reduced cardiovascular strain by preserving PV and attenuating HR, albeit with no corresponding benefit on thermoregulatory function. The former response may facilitate improvements in exercise performance.
... The effects of rehydration with different types of fluid intake such as water or sport drinks on performance have been widely investigated among athletes [7][8][9][10][11][12][13]. However, there is a lack of studies that have investigate the effect of rehydration with Zamzam water on hydration status among athletes. ...
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Background: the present study aimed to examine the effect of rehydration with mineral water on cardiorespiratory fitness in athletes. Methods: Twenty athletes (21.7±3 years) randomly underwent a crossover design experimental trial. Three visits were arranged. The first visit was for baseline measurement. The second visit included three phases (pre-dehydration, post-dehydration, and post-rehydration), and either Zamzam (mineral water) or bottled water (control water) was used. The third visit was similar to the second visit with an exchange for the type of water. Cardiorespiratory fitness and blood parameters have been evaluated. Data were analyzed to compare the results of Zamzam water with bottled water and to compare the phases for each type of water. Results: although there was no significant difference found between Zamzam and bottled water in the cardiorespiratory fitness markers, Zamzam water maintained cardiorespiratory function including VO2peak, VT1, VT2, and VEpeak even with rehydration equal to 100% of losing body mass following exercise-induced dehydration (>-2% body mass), where rehydration with bottle water reported a significant reduction in both VO2peak and VEpeak. Conclusion: rehydration with mineral water such as Zamzam water may not impair cardiorespiratory fitness even with an amount equal to 100% of losing body mass.
... be to some extent common. This may also happen in situations of diminished5 fluid intake or as a result of consumption of diuretics. The loss of body fluids outstripping the amount which 1 is taken in, interrupting the delicate equilibrium of minerals in body fluids, culminates in dehydration. ...
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Water is an essential component in terms of having a role in building of human body. The total body watercontent must be adequately maintained for the health and wellbeing of an individual. Water intake as well aswater loss is governed by efficacious homeostatic mechanisms which are receptive to even minute changessuch as hundred milliliters. Water deficit happens as hypohydration when fluid intake is not sufficient to replacefluid losses. When water loss exceeds the amount of water consumed, dehydration results. Mild dehydration isdescribed as fluid loss being around 1-2% of total body fluids. Severe dehydration occurs with fluid loses over5%. Dehydration has remarkable consequences including effect on body temperature, respiratory rate, mentalfunctioning and muscle endurance. Overall, the role of water as a necessary nutrient is indispensable.Consequently, appropriate hydration status is extremely imperative for health and wellbeing of an individual.1 The human body contains around 70% of water. In terms of body weight water makes up 75% in infants and55% in elderly. Water is necessary for cellular homeostasis as well as life. Still plentiful unanswered2 questions exist regarding this extremely imperative constituent of our body and our diet. The water in the1 body has diverse physiological roles. These include being required for breathing for oxygen transport to thecells, metabolism, digestion and absorption of nutrients, detoxification of the body, regulation of body1 temperature, upkeep of equal osmotic pressure in cells as well as extracellular space etc. Water should betreated as vital nutrient in diet. Accordingly, it is imperative for health to have total body water (TBW) contentin appropriate standards.
... But now a day's sports drinks are made of with different combinations of nutrients so diverse sports drinks are available in the market. Therefore intake of sports drinks helps us to maintain our intra cellular and extracellular water balance (Shirreffs, 2009). ...
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Optimal hydration is an essential consideration for athletic performance and it involves activities before, during and after exercise. Hence, adequate hydration not only provides benefits for health but also facilitate to maintain athletic performance. Therefore, the objective of the present study is to evaluate the importance of sports drinks as a performance prerequisites. The central aim of sports drinks utilization differ according to the mode of exercise regime but from a hydration point of view it depends upon rapid fluid absorption, reduction of physiological stress and faster recovery after exercise. So, proper intake of different essential macro and micro nutrients will help our body to hydrate. Sports drinks is a such a product which contain almost all the things which we lost during sports performance. Similarly, dehydration is a condition which cause negative impact on sports performance. The performance of the athlete is very much depends upon their hydration point of view, which may lead to cause both psychological as well as physiological illness. During activity the major fluid loss occurs through sweat. Thus it causes increment of heart rate, body temperature and also reduces the fluid absorption rate, making out body resistive against the minimum demand of work. All these problems can be overcome with the help of isotonic sports drinks. It helps replenish the lost fluid and also provide essential electrolytes and carbohydrates to the athletes which ultimately helped them to execute better performance output.
... Seemingly marginal improvements in late-race performance, therefore, can substantially affect race outcomes. While a plethora of studies have compared the impact of consumption of sports drinks vs. water on performance and have been reviewed elsewhere (Shirreffs and Maughan, 2000;Shirreffs, 2009;Temesi et al., 2011;Orru et al., 2018), none to our knowledge have examined how rehydration with these distinct solutions may differentially impact performance during the important final stages of a race, i.e., the final push to the finish line after a dehydrating exercise bout. To our knowledge, no previous studies have compared the rehydration capabilities of a beverage containing ultra-filtered deproteinized milk and a traditional sports drink and their subsequent influence on performance. ...
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Dehydration ≥2% loss of body mass is associated with reductions in performance capacity, and carbohydrate (CHO)-electrolyte solutions (CES) are often recommended to prevent dehydration and provide a source of exogenous carbohydrate during exercise. It is also well established that performance capacity in the heat is diminished compared to cooler conditions, a response attributable to greater cardiovascular strain caused by high skin and core temperatures. Because hydration status, environmental conditions, and carbohydrate availability interact to influence performance capacity, we sought to determine how these factors affect push-to-the-finish cycling performance. Ten young trained cyclists exercised at a moderate intensity (2.5 W·kg⁻¹) in a hot-dry condition [40°C, 20% relative humidity (RH)] until dehydration of ~2% body mass. Subjects then consumed either no fluid (NF) or enough fluid (water, WAT; Gatorade®, GAT; or GoodSport™, GS) to replace 75% of lost body mass over 30 min. After a 30-min light-intensity warm-up (1.5 W·kg⁻¹) in a 35°C, 20% RH environment, subjects then completed a 120-kJ time trial (TT). TT time-to-completion, absolute power, and relative power were significantly improved in WAT (535 ± 214 s, 259 ± 99 W, 3.3 ± 0.9 W·kg⁻¹), GAT (539 ± 226 s, 260 ± 110 W, 3.3 ± 1.0 W·kg⁻¹), and GS (534 ± 238 s, 262 ± 105 W, 3.4 ± 1.0 W·kg⁻¹) compared to NF (631 ± 310 s, 229 ± 96 W, 3.0 ± 0.9 W·kg⁻¹) all (p < 0.01) with no differences between WAT, GAT, and GS, suggesting that hydration is more important than carbohydrate availability during exercise in the heat. A subset of four subjects returned to the laboratory to repeat the WAT, GAT, and GS treatments to determine if between-beverage differences in time-trial performance were evident with a longer TT in thermoneutral conditions. Following dehydration, the ambient conditions in the environmental chamber were reduced to 21°C and 20% RH and subjects completed a 250-kJ TT. All four subjects improved TT performance in the GS trial (919 ± 353 s, 300 ± 100 W, 3.61 ± 0.86 W·kg⁻¹) compared to WAT (960 ± 376 s, 283 ± 91 W, 3.43 ± 0.83 W·kg⁻¹), while three subjects improved TT performance in the GAT trial (946 ± 365 s, 293 ± 103 W, 3.60 ± 0.97 W·kg⁻¹) compared to WAT, highlighting the importance of carbohydrate availability in cooler conditions as the length of a push-to-the-finish cycling task increases.
... In young children, both athletes or not, the increased intake of soft drinks or the consumption of food rich in SF could have a negative impact on bone health and performance due to the impact of these on calcium absorption. This is the reason why it may be important to suggest using unsweetened drinks (water and milk) or orange juice, or sports drinks but only with small amounts of carbohydrate (<2%) and moderate amounts of sodium (37) and fortified with calcium in order to obtain rehydration and reduce or prevent loss of BMD. Furthermore, following a healthy diet rich in unsaturated fat is also suggested. ...
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There is growing recognition of the role of diet and physical activity in modulating bone mineral density, bone mineral content, and remodeling, which in turn can impact bone health later in life. Adequate nutrient composition could influence bone health and help to maximize peak bone mass. Therefore, children’s nutrition may have lifelong consequences. Also, physical activity, adequate in volume or intensity, may have positive consequences on bone mineral content and density and may preserve bone loss in adulthood. Most of the literature that exists for children, about diet and physical activity on bone health, has been translated from studies conducted in adults. Thus, there are still many unanswered questions about what type of diet and physical activity may positively influence skeletal development. This review focuses on bone requirements in terms of nutrients and physical activity in childhood and adolescence to promote bone health. It explores the contemporary scientific literature that analyzes the impact of diet together with the typology and timing of physical activity that could be more appropriate depending on whether they are children and adolescents to assure an optimal skeleton formation. A description of the role of parathyroid hormone (PTH) and gut hormones (gastric inhibitory peptide (GIP), glucagon-like peptide (GLP)-1, and GLP-2) as potential candidates in this interaction to promote bone health is also presented.
... During the experimental session (see below), the participants consumed one of three carbohydrates-electrolytes beverages consisting of 6.5 g of isomaltulose (ISO), 6.5 g of sucrose (SUC), and 3.25 g of glucose plus 3.25 g of fructose (G + F) as carbohydrates per 100 ml solutions, respectively. These carbohydrate concentrations are commonly found in commercial sports beverages [23]. A list of nutrients contained in each beverage is presented in Table 1. ...
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PurposeIsomaltulose is a low glycemic and insulinaemic carbohydrate available as a constituent in sports drink. However, it remains unclear whether postexercise rehydration achieved by isomaltulose drink ingestion alone differs as compared to other carbohydrates.Methods Thirteen young men performed intermittent exercise in the heat (35 °C and relative humidity 40%) to induce a state of hypohydration as defined by a 2% loss in body mass. Thereafter, participants were rehydrated by ingesting drinks equal to the volume of body mass loss with either a mixture of 3.25% glucose and 3.25% fructose, 6.5% sucrose (SUC), or 6.5% isomaltulose (ISO) within the first 30 min of a 3-h recovery. The change in plasma volume (ΔPV) from pre-exercise baseline, blood glucose, and plasma insulin concentration were assessed every 30-min.ResultsΔPV was lower in ISO as compared to SUC until 90 min of the recovery (all P ≤ 0.038) with no difference thereafter (all P ≥ 0.391). The ΔPV were paralleled by concomitant changes in blood glucose levels that were greater in ISO as compared to other drinks after 90 min of the recovery (all P ≤ 0.035). Plasma insulin secretion, which potentially enhances renal sodium reabsorption and fluid retention, did not differ between the trials (interaction, P = 0.653). ISO induced a greater net fluid volume retention as compared to SUC (P = 0.010).Conclusion We showed that rehydration with an isomaltulose drink following exercise-heat stress induces comparable recovery of PV and a greater net fluid retention as compared to other drinks, albeit this response is delayed. The delayed water transport along with glucose absorption may modulate this response.This trial was registered in 25th Sep 2019 at https://www.umin.ac.jp/ as UMIN000038099.(249/250)
... In SPD, appearance liking increased significantly in all viscosity ranges (Table 3). Once the consumer learned the importance of hydration in elderly people with swallowing difficulties, they might have considered the sports drink to be a good source of hydration, as it was designed for rehydration during or after exercise [52]. ...
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: Most people tend to think that healthy foods do not taste good. This view could have a negative impact on the taste of the food that people eat for health. However, if health-related information is provided to avoid negative aspects, acceptability may improve. Thus, this study investigated changes in consumers’ sensory perception of thickened beverages before and after the provision of dysphagia-related health information. Sixty young (19–39 years old) and middle-aged (40–64 years old) consumers participated in two experiment sessions conducted one week apart. The first session proceeded without any information and the second provided information about dysphagia and the need for dietary modification before evaluation. Three beverages (orange juice, red bean water, and sports drink) were used in nectar-like (51–350 cP) and honey-like (351–1750 cP) forms; original beverage samples (0%) were used as the control. Consumers were asked about acceptability, liking the flavor, intensity, and general health interest (GHI). An analysis of variance was performed to show the change in flavor rating and acceptability between the two sessions. Although there were age-related differences in response to the samples, thickened beverages were rated as more acceptable, in terms of their characteristics (swallowing, viscosity, and mouthfeel) after the information was provided. There were no significant differences for the 0% samples. The mean GHI values were 3.97 ± 0.85 and 4.81 ± 0.68 for the young and middle-aged groups, respectively. High and low GHI groups were analyzed. The high GHI group showed significant differences in acceptability in the informed evaluation, whereas the low GHI group was not influenced by the information.
... Consumption of fluids containing carbohydrates and electrolytes is recommended before and during exercise in a hot environment to maintain muscle glucose metabolism and fluid balance as well as physiological function, including thermoregulatory and cardiovascular responses [1][2][3]. Conventional sports drinks contain carbohydrates such as glucose, fructose, maltodextrin, and sucrose. Isomaltulose (ISO) is a naturally occurring disaccharide composed of α-1, 6-linked glucose, and fructose, in contrast to the α-1, 2glycosidic bond found in sucrose (SUC). ...
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Isomaltulose is a low glycemic and insulinemic carbohydrate available as a constituent of sports drinks. However, it remains unclear whether thermoregulatory responses (sweating and cutaneous vasodilation) after isomaltulose drink ingestion differ from those of sucrose and water during exercise in a hot environment. Ten young healthy males consumed 10% sucrose, 10% isomaltulose, or water drinks. Thirty-five minutes after ingestion, they cycled for fifteen minutes at 75% peak oxygen uptake in a hot environment (30 °C, 40% relative humidity). Sucrose ingestion induced greater blood glucose concentration and insulin secretion at the pre-exercise state, compared with isomaltulose and/or water trials, with no differences during exercise in blood glucose. Change in plasma volume did not differ between the three trials throughout the experiment, but both sucrose and isomaltulose ingestions similarly increased plasma osmolality, as compared with water (main beverage effect, p = 0.040)—a key response that potentially delays the onset of heat loss responses. However, core temperature thresholds and slopes for heat loss responses were not different between the trials during exercise. These results suggest that ingestion of isomaltulose beverages induces low glycemic and insulinemic states before exercise but does not alter thermoregulatory responses during exercise in a hot environment, compared with sucrose or water.
... Dehydration has been shown to decrease performance by impairing cognitive function and weakening muscle contraction (12). The recovery process also relies on hydration because of the role of water in maintaining blood volume, regulating body temperature, and promoting muscle repair (69). Athletes should then aim to consume 2-4 L per day and 150% of the fluids lost after exercise sessions (77). ...
Article
The rapid growth in trick progression for competitive snowboarding over the past 20 years has resulted in increased physical demands required from snowboarding athletes. Despite a wealth of knowledge surrounding strength and conditioning principles for other sports, researchers are yet to address the novel strength and conditioning challenges faced by the freestyle nature of competitive snowboarding. This article, therefore, offers practitioners strategies to address the unique considerations surrounding cultural qualities, injury prevention, unstable surface training, skill acquisition, and recovery strategies for the effective implementation of strength and conditioning interventions for snowboarding athletes.
Chapter
Hydration is essential for athletic performance and overall health, yet many athletes face challenges in achieving it. A cross-sectional study was conducted on the Ankaragücü youth soccer team in Turkey to assess hydration status. Twenty-six male athletes (15 ± 1.2 years) participated, with data collected over 3 days, including body weight, fluid volume changes, and urinalysis. Hydration was assessed by urine specific gravity (USG), osmolality, and urine color. Results showed a mean daily fluid consumption of 2780 ± 567 mL, of which 908.6 ± 332.7 mL was consumed during training. Dehydration levels averaged 0.5% over the two training days. Urinalysis showed a strong correlation between USG (strip) with both USG (laboratory) and USG (refractometry) (r = 0.8; P < 0.01) and with osmolality (r = 0.7; P < 0.01), while its association with urine color was moderate (r = 0.4; P < 0.05). Despite adequate hydration, some athletes completed training in a dehydrated state, highlighting the need for improved hydration strategies. This study highlights the effectiveness of urine strips for practical, field-based hydration assessment and emphasizes the importance of hydration education for young athletes to prevent dehydration and enhance performance.
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Sports drinks typically contain high levels of carbs, which are a useful energy source. Sports drinks also help to keep the body in balance, enhance performance, and include several electrolytes that, when taken before or during intense activity, can enhance performance. Sports drink formulations should take into account the individual energy, nutritional, fluid, and electrolyte requirements of athletes, taking into account the phase of exercise (before, during, or after). A balanced, healthy diet that includes chia seeds and regular exercise can help athletes meet their performance objectives while also maintaining their general health.
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Hypohydration can impair aerobic performance and deteriorate cognitive function during exercise. To minimize hypohydration, athletes are recommended to commence exercise at least euhydrated, ingest fluids containing sodium during long-duration and/or high-intensity exercise to prevent body mass loss over 2% and maintain elevated plasma osmolality, and rapidly restore and retain fluid and electrolyte homeostasis before a second exercise session. To achieve these goals, the compositions of the fluids consumed are key; however, it remains unclear what can be considered an optimal formulation for a hydration beverage in different settings. While carbohydrate–electrolyte solutions such as sports drinks have been extensively explored as a source of carbohydrates to meet fuel demands during intense and long-duration exercise, these formulas might not be ideal in situations where fluid and electrolyte balance is impaired, such as practicing exercise in the heat. Alternately, hypotonic compositions consisting of moderate to high levels of electrolytes (i.e., ≥45 mmol/L), mainly sodium, combined with low amounts of carbohydrates (i.e., <6%) might be useful to accelerate intestinal water absorption, maintain plasma volume and osmolality during exercise, and improve fluid retention during recovery. Future studies should compare hypotonic formulas and sports drinks in different exercise settings, evaluating different levels of sodium and/or other electrolytes, blends of carbohydrates, and novel ingredients for addressing hydration and rehydration before, during, and after exercise.
Article
Aim The purpose of this review was to emphasize the nutritional value, and pharmacological and phytochemical properties of Salvia hispanica, as well as its toxicological evaluation. Background Salvia hispanica L. (S. hispanica), also called chia seeds, is an annual herbaceous plant belonging to the family Lamiaceae. It is a species of medicinal and dietary plant used since ancient times by the Maya and Aztecs. Its product is an indehiscent dry fruit that is commonly called a seed. It is utilized for its health benefits and uses in cooking. Objective The study aimed to investigate the pharmacological, phytochemical, and toxicological properties of S. hispanica seeds. The research also attempted to explore and compile all existing knowledge and data on these seeds' nutritional value and medical applications. Materials and Methods The current review was conducted using numerous scientific databases, including Science Direct, Scopus, PubMed, Google Scholar, etc. The correct plant name was verified from plantlist.org. The results of this search were interpreted, analyzed, and documented based on the obtained bibliographic information. Results S. hispanica is a pseudo cereal that is consumed by the world’s population because of its preventive, functional, and antioxidant characteristics, attributable to the presence of lipids, dietary fiber, protein, phenolic compounds, vitamins, and minerals. According to research, chia offers hypoglycemic, antimicrobial, anticancer, anti-inflammatory, antioxidant, antihypersensitive, anti-obesity, and cardioprotective properties. Chia consumption has grown because of its favorable benefits on obesity, cardiovascular disease, diabetes, and several forms of cancer. These advantages are mostly due to the high concentration of essential fatty acids, dietary fiber, antioxidants, flavonoids, anthocyanins, vitamins, carotenoids, and minerals found in this seed. Based on the beneficial components, chia seeds have enormous potential in the areas of health, food, animal feed, medicines, and nutraceuticals. Finally, toxicological investigations have indicated the greater doses of chia seed extracts as safe. Conclusion The current evaluation has focused on the distribution, chemical composition, nutritional value, and principal uses of S. hispanica in order to determine future research requirements and examine its pharmacological applications through clinical studies.
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Objective: There is a high incidence of concussion and frequent utilization of rapid weight loss (RWL) methods among combat sport athletes, yet the apparent similarity in symptoms experienced as a result of a concussion or RWL has not been investigated. This study surveyed combat sports athletes to investigate the differences in symptom onset and recovery between combat sports and evaluated the relationships between concussion and RWL symptoms. Design: Cross-sectional study. Setting: Data were collected through an online survey. Participants: One hundred thirty-two (115 male athletes and 17 female athletes) combat sport athletes. Interventions: Modified Sport Concussion Assessment Tool (SCAT) symptom checklist and weight-cutting questionnaire. Main outcome measures: Survey items included combat sport discipline, weight loss, medical history, weight-cutting questionnaire, and concussion and weight-cutting symptom checklists. Results: Strong associations (rs = 0.6-0.7, P < 0.05) were observed between concussion and RWL symptoms. The most frequently reported symptom resolution times were 24 to 48 hours for a weight cut (WC; 59%) and 3 to 5 days for a concussion (43%), with 60% to 70% of athletes reporting a deterioration and lengthening of concussion symptoms when undergoing a WC. Most of the athletes (65%) also reported at least one WC in their career to "not go according to plan," resulting in a lack of energy (83%) and strength/power (70%). Conclusions: Rapid weight loss and concussion symptoms are strongly associated, with most of the athletes reporting a deterioration of concussion symptoms during a WC. The results indicate that concussion symptoms should be monitored alongside hydration status to avoid any compound effects of prior RWL on the interpretation of concussion assessments and to avoid potential misdiagnoses among combat athletes.
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Atletska gibanja izvorni su oblici kretanja s najizraženijom filogenetskom komponentom u kojoj su se kao fundamentalna generička motorička znanja održala od postanka čovjeka do danas (Burton, 1998). Opće je poznata uzrečica kako je atletika “kraljica sportova”. Neizbježan faktor koji se veže uz atletiku je hidracija. Naime, voda čini 60% tijela zrelog muškarca, kod beba i male djece ta je količina 80%, a kod žena 55% (Roganović, 2011). Potrebe za vodom su individualne i razlikuju se od osobe do osobe, te stoga ne možemo utvrditi jedan univerzalni plan unosa tekućine za sve ljude. U ovom radu nastojat će se utvrditi razlike u stanju hidriranosti trkača na srednje i duge pruge, razlike u motivacijskim profilima te povezanost stanja hidriranosti i motivacije.
Article
Purpose The purpose of this study was to confirm and evaluate the assessment of dehydration, whole body sweat rate, sweat sodium · potassium concentration, and fluid intake during workout in college badminton and rugby athletes using the field sweat test. Methods 14 male badminton athletes and 17 male rugby athletes were measured during an usual training session in a typical environment. USG(urine specific gravity) was measured before the start of training. Whole body sweat rate, sweat sodium·potassium concentration, and fluid intake were measured during and post a session of training. Results USG higher than 1.023 in both groups, which was considered as dehydrated. Sweating rate were 1.037±0.315L/h for the badminton athletes and 1.987±0.386L/h for the rugby athletes. The concentration of sodium and potassium were 53.6±20.2mmol/L, 4.1±0.7mmol/L for badminton athletes, and 55.6±15.2mmol/L, 4.3±0.5mmol/L for rugby athletes, respectively. The loss of sodium and potassium were 1.02±0.48g, 0.08±0.02g for badminton athletes, and 1.95±0.52g, 0.15±0.03g for rugby athletes, respectively. Conclusions In this study, a standard protocol of field sweat test was suggested as a useful factor in evaluating athletes' hydration status and electrolyte loss during a routine in-door or out-door training session. And, it is expected to build reliable data to establish a standard hydration guideline for Korean athletes.
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Dehydration during exercise has been shown to limit performance. This study aimed to determine the best hydrocolloid for producing sports energy gel from chia seeds (Salvia hispanica L.). This study was a completed random-design study using one factor: the addition of 0.1% w/w hydrocolloids (SEG1: xanthan gum; SEG2: pectin; and SEG3: carboxymethyl cellulose). A sports energy gel was then analyzed for pH, viscosity, total soluble solids, potassium content, and gross energy. The sensory characteristics that were analyzed include color, texture, aroma, and flavor, using hedonic tests on 25 panelists. The addition of different hydrocolloids resulted in significant differences in pH, viscosity, total soluble solids, potassium, and energy contents (p = 0.026; 0.0001; 0.0001; and 0.0001). Differences in hydrocolloid types also led to differences in the panelists’ perceptions of the sports energy gels’ colors and textures (p = 0.008 and 0.0001). The best formulation was the sports energy gel with added xanthan gum, which showed the highest average energy, total soluble solids, potassium, and viscosity values, and the lowest average of pH values (60.24 ± 0.340, 10.6 ± 0.08, 19.6 ± 0.23, 367.4 ± 9.81, and 5.2 ± 0.38, respectively). The conclusion is that chia seeds can be used as the main ingredient for producing a high-energy sports gel. Energy has a huge impact on a person’s physical and mental health.
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The effectiveness of different carbohydrate solutions in restoring fluid balance in situations of voluntary fluid intake has not been examined previously. The effect of the carbohydrate content of drinks ingested after exercise was examined in 6 males and 3 females previously dehydrated by 1.99 0.07% of body mass via intermittent exercise in the heat. Beginning 30min after the cessation of exercise, subjects drank ad libitum for a period of 120min. Drinks contained 31mmolL¹ Na⁺ as NaCl and either 0%, 2%, or 10% glucose with mean SD osmolalities of 74 1, 188 3, and 654 4 mosmkg¹, respectively. Blood and urine samples were collected before and after exercise, midway through rehydration, and throughout a 5h recovery period. Total fluid intake was not different among trials (0%: 2258 519mL; 2%: 2539 436mL; 10%: 2173 252mL; p = 0.173). Urine output was also not different among trials (p = 0.160). No differences among trials were observed in net fluid balance or in the fraction of the ingested drink retained. In conclusion, in situations of voluntary fluid intake, hypertonic carbohydrate-electrolyte solutions are as effective as hypotonic carbohydrate-electrolyte solutions at restoring whole-body fluid balance.
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To investigate the effect of drink temperature on cycling capacity in the heat. On two separate trials, eight males cycled at 66 +/- 2% VO2peak (mean +/- SD) to exhaustion in hot (35.0 +/- 0.2 degrees C) and humid (60 +/- 1%) environments. Participants ingested three 300-mL aliquots of either a cold (4 degrees C) or a warm (37 degrees C) drink during 30 min of seated rest before exercise and 100 mL of the same drink every 10 min during exercise. Rectal and skin temperatures, heart rate, and sweat rate were recorded. Ratings of thermal sensation and perceived exertion were assessed. Exercise time was longer (P < 0.001) with the cold drink (63.8 +/- 4.3 min) than with the warm drink (52.0 +/- 4.1 min). Rectal temperature fell by 0.5 +/- 0.1 degrees C (P < 0.001) at the end of the resting period after ingestion of the cold drinks. There was no effect of drink temperature on mean skin temperature at rest (P = 0.870), but mean skin temperature was lower from 20 min during exercise with ingestion of the cold drink than with the warm drink (P < 0.05). Heart rate was lower before exercise and for the first 35 min of exercise with ingestion of the cold drink than with the warm drink (P < 0.05). Drink temperature influenced sweat rate (1.22 +/- 0.34 and 1.40 +/- 0.41 L x h(-1) for the cold and the warm drink, respectively; P < 0.05). Ratings of thermal sensation and perceived exertion (P < 0.01) during exercise were lower when the cold drink was ingested. Compared with a drink at 37 degrees C, the ingestion of a cold drink before and during exercise in the heat reduced physiological strain (reduced heat accumulation) during exercise, leading to an improved endurance capacity (23 +/- 6%).
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This study examined effects of ingesting a 10% carbohydrate (CHO) drink (CI) or placebo (PI) at 500 ml/h on total (splanchnic) glucose appearance (endogenous+exogenous; Ra), blood glucose oxidation, and muscle glycogen utilization in 14 male endurance-trained cyclists who rode for 180 min at 70% of maximal O2 uptake after CHO loading [starting muscle glycogen 203 +/- 7 (SE) mmol/kg wet wt]. Total CHO oxidation was similar in CI and PI, but Ra increased significantly during the trial in both groups with CI reaching a plateau after 75 min. Ra was significantly greater in CI than in PI at the end of exercise. Blood glucose oxidation also increased significantly during the trial to a plateau in CI and was significantly higher in CI than in PI at the end of exercise. However, mean endogenous Ra was significantly lower in CI than in PI throughout exercise, as was oxidation of endogenous blood glucose, which remained almost constant in CI and reached 43 +/- 8 and 73 +/- 13 mumol.min-1.kg fat-free mass-1 in CI and PI, respectively, at the end of exercise. At 0.83 g/min of CHO ingestion, 0.77 +/- 0.03 g/min was oxidized. Muscle glycogen utilization was identical in both groups and was higher during the 1st h of exercise.(ABSTRACT TRUNCATED AT 250 WORDS)
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Dehydration alters cardiovascular, thermoregulatory, central nervous system, and metabolic functions. One or more of these alterations will degrade endurance exercise performance when dehydration exceeds 2% of body weight. These performance decrements are accentuated by heat stress. To minimize the adverse consequences of body water deficits on endurance exercise performance, it is recommended that fluid intake be sufficient to minimize dehydration to less than 2% of body weight loss. This can usually be achieved with fluid intakes of under 1 L x h(-1).
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The high metabolic rates sustained by soccer players during training and match-play cause sweat to be produced in both warm and temperate environments. There is limited published information available on the effects of this sweat loss on performance in soccer. However, this limited information, together with knowledge of the effects of sweat loss in other sports with skill components as well as endurance and sprint components, suggests that the effects of sweating will be similar to the effects in these other activities. Therefore, the generalization that a body mass reduction equivalent to 2% should be the acceptable limit of sweat losses seems reasonable. This amount, or more, of sweat loss reflected in body mass loss is a common experience for some players. Sodium is the main electrolyte lost in sweat and the available data indicate considerable variability in sodium losses between players due to differences in sweating rate and sweat electrolyte concentration. Additionally, the extent of sodium loss is such that its replacement will be warranted for some of these players during training sessions and matches. Although soccer is a team sport, the great individual variability in sweat and electrolyte losses of players in the same training session or match dictates that individual monitoring to determine individual water and electrolyte requirements should be an essential part of a player's nutritional strategy.
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Nine males cycled at 53% (s = 2) of their peak oxygen uptake (VO(2peak)) for 90 min (dry bulb temperature: 25.4 degrees C, s = 0.2; relative humidity: 61%, s = 3). One litre of flavoured water at 10 (cold), 37 (warm) or 50 degrees C (hot) was ingested 30 - 40 min into exercise. Immediately after the 90 min of exercise, participants cycled at 95%VO(2peak) to exhaustion to assess exercise capacity. Rectal and mean skin temperatures and heart rate were recorded. The gradient of rise in rectal temperature was influenced (P < 0.01) by drink temperature. Mean skin temperature was highest in the hot trial (cold trial: 34.2 degrees C, s = 0.5; warm trial: 34.4 degrees C, s = 0.5; hot trial: 34.7 degrees C, s = 0.6; P < 0.01). Significant differences were observed in heart rate (cold trial: 132 beats . min(-1), s = 13; warm trial: 134 beats . min(-1), s = 12; hot trial: 139 beats . min(-1), s = 13; P < 0.05). Exercise capacity was similar between trials (cold trial: 234 s, s = 69; warm trial: 214 s, s = 52; hot trial: 203 s, s = 53; P = 0.562). The heat load and debt induced via drinking resulted in appropriate thermoregulatory reflexes during exercise leading to an observed heat content difference of only 33 kJ instead of the predicted 167 kJ between the cold and hot trials. These results suggest that there may be a role for drink temperature in influencing thermoregulation during exercise.
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Significant scientific evidence documents the deleterious effects of hypohydration (reduced total body water) on endurance exercise performance; however, the influence of hypohydration on muscular strength, power and high-intensity endurance (maximal activities lasting >30 seconds but <2 minutes) is poorly understood due to the inconsistent results produced by previous investigations. Several subtle methodological choices that exacerbate or attenuate the apparent effects of hypohydration explain much of this variability. After accounting for these factors, hypohydration appears to consistently attenuate strength (by approximately 2%), power (by approximately 3%) and high-intensity endurance (by approximately 10%), suggesting alterations in total body water affect some aspect of force generation. Unfortunately, the relationships between performance decrement and crucial variables such as mode, degree and rate of water loss remain unclear due to a lack of suitably uninfluenced data. The physiological demands of strength, power and high-intensity endurance couple with a lack of scientific support to argue against previous hypotheses that suggest alterations in cardiovascular, metabolic and/or buffering function represent the performance-reducing mechanism of hypohydration. On the other hand, hypohydration might directly affect some component of the neuromuscular system, but this possibility awaits thorough evaluation. A critical review of the available literature suggests hypohydration limits strength, power and high-intensity endurance and, therefore, is an important factor to consider when attempting to maximise muscular performance in athletic, military and industrial settings.
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In this study, we examined thermoregulatory responses to ingestion of separate aliquots of drinks at different temperatures during low-intensity exercise in conditions of moderate heat stress. Eight men cycled at 50% (s = 3) of their peak oxygen uptake (VO2peak) for 90 min (dry bulb temperature: 25.3 degrees C, s = 0.5; relative humidity: 60%, s = 5). Four 400-ml aliquots of flavoured water at 10 degrees C (cold), 37 degrees C (warm) or 50 degrees C (hot) were ingested after 30, 45, 60, and 75 min of exercise. Immediately after the 90 min of exercise, participants cycled at 95% VO2peak to exhaustion to assess exercise capacity. There were no differences between trials in rectal temperature at the end of the 90 min of exercise (cold: 38.11 degrees C, s = 0.30; warm: 38.10 degrees C, s = 0.33; hot: 38.21 degrees C, s = 0.30; P = 0.765). Mean skin temperature between 30 and 90 min tended to be influenced by drink temperature (cold: 34.49 degrees C, s = 0.64; warm: 34.53 degrees C, s = 0.69; hot: 34.71 degrees C, s = 0.48; P = 0.091). Mean heart rate from 30 to 90 min was higher in the hot trial (129 beats . min(-1), s = 7; P < 0.05) than on the cold (124 beats . min(-1), s = 9) and warm trials (126 beats . min(-1), s = 8). Ratings of thermal sensation were higher on the hot trial than on the cold trial at 35 and 50 min (P < 0.05). Exercise capacity was similar between trials (P = 0.963). The heat load and debt induced by periodic drinking resulted in similar body temperatures during low-intensity exercise in conditions of moderate heat stress due to appropriate thermoregulatory reflexes.
Article
This study assessed whether replacing sweat losses with sodium-free fluid can lower the plasma sodium concentration and thereby precipitate the development of hyponatremia. Ten male endurance athletes participated in one 1-h exercise pretrial to estimate fluid needs and two 3-h experimental trials on a cycle ergometer at 55% of maximum O 2 consumption at 34°C and 65% relative humidity. In the experimental trials, fluid loss was replaced by distilled water (W) or a sodium-containing (18 mmol/l) sports drink, Gatorade (G). Six subjects did not complete 3 h in trial W, and four did not complete 3 h in trial G. The rate of change in plasma sodium concentration in all subjects, regardless of exercise time completed, was greater with W than with G (−2.48 ± 2.25 vs. −0.86 ± 1.61 mmol ⋅ l ⁻¹ ⋅ h ⁻¹ , P = 0.0198). One subject developed hyponatremia (plasma sodium 128 mmol/l) at exhaustion (2.5 h) in the W trial. A decrease in sodium concentration was correlated with decreased exercise time ( R = 0.674; P = 0.022). A lower rate of urine production correlated with a greater rate of sodium decrease ( R = −0.478; P = 0.0447). Sweat production was not significantly correlated with plasma sodium reduction. The results show that decreased plasma sodium concentration can result from replacement of sweat losses with plain W, when sweat losses are large, and can precipitate the development of hyponatremia, particularly in individuals who have a decreased urine production during exercise. Exercise performance is also reduced with a decrease in plasma sodium concentration. We, therefore, recommend consumption of a sodium-containing beverage to compensate for large sweat losses incurred during exercise.
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Six well-trained men (peak pulmonary oxygen uptake = 5.03 +/- 0.11 l/min) were studied during 2 h of exercise at 69 +/- 1% peak pulmonary oxygen uptake to examine the effect of carbohydrate (CHO) ingestion on glucose kinetics. Subjects ingested 250 ml of either a 10% glucose solution containing 6-[3H]glucose (CHO) or a sweet placebo every 15 min during exercise. Glucose kinetics were assessed by 6,6-[2H]glucose infusion corrected for gut-derived glucose in CHO. Plasma glucose was higher (P < 0.05) in CHO from 20 min. Total glucose appearance was higher in CHO due to glucose delivery from the gut (68 +/- 7 g), since hepatic glucose production was reduced by 51% (29 +/- 5 vs. 59 +/- 5 g). Glucose uptake was higher in CHO (96 +/- 7 vs. 60 +/- 6 g) with the ingested glucose supplying 67 +/- 4 g and, with the assumption that it was fully oxidized, accounted for 14 +/- 1% of total energy expenditure. In conclusion, CHO ingestion during prolonged exercise results in suppression of hepatic glucose production and increased glucose uptake. These effects appear to be mediated mainly by increased plasma glucose and insulin levels.
Article
Four athletes developed water intoxication (hyponatremia) during endurance events lasting more than 7 h. The etiology of the condition appears to be voluntary hyperhydration with hypotonic solutions combined with moderate sweat sodium chloride losses. The reason why the fluid excess in these runners was not corrected by increased urinary losses is unknown. When advised to drink less during prolonged exercise, three of the athletes have subsequently completed prolonged endurance events uneventfully. (C)1985The American College of Sports Medicine
Article
Significant scientific evidence documents the deleterious effects of hypohydration (reduced total body water) on endurance exercise performance; however, the influence of hypohydration on muscular strength, power and high-intensity endurance (maximal activities lasting >30 seconds but <2 minutes) is poorly understood due to the inconsistent results produced by previous investigations. Several subtle methodological choices that exacerbate or attenuate the apparent effects of hypohydration explain much of this variability. After accounting for these factors, hypohydration appears to consistently attenuate strength (by ≈2%), power (by ≈3%) and high-intensity endurance (by ∼10%), suggesting alterations in total body water affect some aspect of force generation. Unfortunately, the relationships between performance decrement and crucial variables such as mode, degree and rate of water loss remain unclear due to a lack of suitably uninfluenced data. The physiological demands of strength, power and high-intensity endurance couple with a lack of scientific support to argue against previous hypotheses that suggest alterations in cardiovascular, metabolic and/or buffering function represent the performance-reducing mechanism of hypohydration. On the other hand, hypohydration might directly affect some component of the neuromuscular system, but this possibility awaits thorough evaluation. A critical review of the available literature suggests hypohydration limits strength, power and highintensity endurance and, therefore, is an important factor to consider when attempting to maximise muscular performance in athletic, military and industrial settings.
Article
This study investigated the effect of the osmolality and carbohydrate content of drinks on their rehydration effectiveness after exercise-induced dehydration. Six healthy male volunteers were dehydrated by 1.9+/-0.1% of body mass by intermittent cycle ergometer exercise in the heat before ingesting one of three solutions with different carbohydrate contents and osmolalities over a period of 1h. Thirty minutes after the cessation of exercise, subjects drank a volume that amounted to 150% (130-150, median [range]) of their body mass loss. Drinks contained 25 mmol/L Na(+) and 0%, 2%, or 10% glucose with osmolalities of (mean+/-SD) 79+/-4, 193+/-5, and 667+/-12 mosm/kg, respectively. Blood and urine samples were collected before exercise, after exercise, and 0, 1, 2, 3, 4, and 6h after the end of the rehydration period. Significantly more of the ingested fluid was retained in the 10% trial (46+/-9%) than in the 0% trial (27+/-13%), with 40+/-14% retained in the 2% trial. Subjects remained euhydrated for 1h longer in the 10% glucose trial than in the 2% glucose trial. In the 2% glucose trial, plasma volume was elevated immediately after and 1h after rehydration. This study suggests that, following the rehydration protocol used, hypertonic glucose-sodium drinks may be more effective at restoring and maintaining hydration status after sweat loss than more dilute solutions when the sodium concentration is comparable.
Article
The change in blood and plasma volume following ingestion of glucose solutions of varying concentrations was estimated in twelve healthy male volunteers. Subjects consumed, within a 5 min period, 600 ml of a solution containing 0, 2, 5 or 10 % glucose with osmolalities of 0 (sd 0), 111 (sd 1), 266 (sd 7) and 565 (sd 5) mOsm/kg, respectively. Blood samples were collected over the course of 1 h after ingestion at intervals of 10 min. After ingestion of the 2 % glucose solution, plasma volume increased from baseline levels at 20 min. Plasma volume decreased from baseline levels at 10 and 60 min after ingestion of the 10 % glucose solution. Heart rate was elevated at 10 and 60 min after ingestion of the 10 % glucose solution and decreased at 30 and 40 min after ingestion of the 2 % glucose solution relative to the average heart rate recorded before drinking. It is concluded that ingestion of hypertonic, energy-dense glucose solutions results in a decrease in plasma and extracellular fluid volume, most likely due to the net secretion of water into the intestinal lumen.
Article
The purpose of this experiment was to determine whether fluid ingestion attenuates the hyperthermia and cardiovascular drift that occurs during exercise dehydration due to increases in blood volume. In addition, forearm blood flow, which is indicative of skin blood flow, was measured to determine whether the attenuation of hyperthermia and cardiovascular drift during exercise with fluid ingestion is due to higher skin blood flow. On three different occasions, seven trained cyclists [mean age, body weight, and maximum oxygen uptake: 23 +/- 3 yr, 73.9 +/- 10.5 kg, and 4.75 +/- 0.34 (SD) l/min, respectively] cycled at a power output equal to 62-67% maximum oxygen uptake for 2 h in a warm environment (33 degrees C, 50% relative humidity, wind speed 2.5 m/s). During exercise, they randomly received no fluid (NF) or a volume of a carbohydrate-electrolyte fluid replacement solution (FR) sufficient to replace 80 +/- 2% of sweat loss or were intravenously infused with 5.3 ml/kg of a blood volume expander (BVX; 6% dextran in saline). The infusion of 398 +/- 23 ml of BVX maintained blood volume at levels similar to that when 2,404 +/- 103 ml of fluid were ingested during FR and greater than that when no fluid was ingested during the 2nd h of exercise (P less than 0.05). However, BVX and NF resulted in similar esophageal and rectal temperatures, forearm blood flow, and elevations in serum osmolality and sodium concentration during 2 h of exercise.(ABSTRACT TRUNCATED AT 250 WORDS)
Article
This investigation determined the effect of different rates of dehydration, induced by ingesting different volumes of fluid during prolonged exercise, on hyperthermia, heart rate (HR), and stroke volume (SV). On four different occasions, eight endurance-trained cyclists [age 23 +/- 3 (SD) yr, body wt 71.9 +/- 11.6 kg, maximal O2 consumption 4.72 +/- 0.33 l/min] cycled at a power output equal to 62-67% maximal O2 consumption for 2 h in a warm environment (33 degrees C dry bulb, 50% relative humidity, wind speed 2.5 m/s). During exercise, they randomly received no fluid (NF) or ingested a small (SF), moderate (MF), or large (LF) volume of fluid that replaced 20 +/- 1, 48 +/- 1, and 81 +/- 2%, respectively, of the fluid lost in sweat during exercise. The protocol resulted in graded magnitudes of dehydration as body weight declined 4.2 +/- 0.1, 3.4 +/- 0.1, 2.3 +/- 0.1, and 1.1 +/- 0.1%, respectively, during NF, SF, MF, and LF. After 2 h of exercise, esophageal temperature (Tes), HR, and SV were significantly different among the four trials (P < 0.05), with the exception of NF and SF. The magnitude of dehydration accrued after 2 h of exercise in the four trials was linearly related with the increase in Tes (r = 0.98, P < 0.02), the increase in HR (r = 0.99, P < 0.01), and the decline in SV (r = 0.99, P < 0.01). LF attenuated hyperthermia, apparently because of higher skin blood flow, inasmuch as forearm blood flow was 20-22% higher than during SF and NF at 105 min (P < 0.05). There were no differences in sweat rate among the four trials. In each subject, the increase in Tes from 20 to 120 min of exercise was highly correlated to the increase in serum osmolality (r = 0.81-0.98, P < 0.02-0.19) and the increase in serum sodium concentration (r = 0.87-0.99, P < 0.01-0.13) from 5 to 120 min of exercise. In summary, the magnitude of increase in core temperature and HR and the decline in SV are graded in proportion to the amount of dehydration accrued during exercise.
Article
This study examined the influence of both hydration and blood glucose concentration on cardiovascular drift during exercise. We first determined if the prevention of dehydration during exercise by full fluid replacement prevents the decline in stroke volume (SV) and cardiac output (CO) during prolonged exercise. On two occasions, 10 endurance-trained subjects cycled an ergometer in a 22 degrees C room for 2 h, beginning at 70 +/- 1% maximal O2 uptake (VO2max) and in a euhydrated state. During one trial, no fluid (NF) replacement was provided and the subject's body weight declined 2.09 +/- 0.19 kg or 2.9%. During the fluid replacement trial (FR), water was ingested at a rate that prevented body weight from declining after 2 h of exercise (i.e., 2.34 +/- 0.17 1/2 h). SV declined 15% and CO declined 7% during the 20- to 120-min period of the NF trial while heart rate (HR) increased 10% and O2 uptake (VO2) increased 6% (all P less than 0.05). In contrast, SV was maintained during the 20- to 120-min period of FR while HR increased 5% and thus CO actually increased 7% (all P less than 0.05). Rectal temperature, SV, and HR were similar during the 1st h of exercise during NF and FR. However, after 2 h of exercise, rectal temperature was 0.6 degree C higher (P less than 0.05) and SV and CO were 11-16% lower (P less than 0.05) during NF compared with FR.(ABSTRACT TRUNCATED AT 250 WORDS)
Article
The availability of carbohydrate (CHO) as a substrate for the exercising muscles is known to be a limiting factor in the performance of prolonged cycle exercise, and provision of exogenous CHO in the form of glucose can increase endurance capacity. The present study examined the effects of ingestion of fluids and of CHO in different forms on exercise performance. Six male volunteers exercised to exhaustion on a cycle ergometer at a workload which required approximately 70% of Vo2max. After one preliminary trial, subjects performed this exercise test on six occasions, one week apart. Immediately before exercise, and at 10-min intervals throughout, subjects ingested 100 ml of one of the following: control (no drink), water, glucose syrup, fructose syrup, glucose-fructose syrup or a dilute glucose-electrolyte solution. Each of the syrup solutions contained approximately 36 g CHO per 100 ml; the isotonic glucose-electrolyte solution contained 4 g glucose per 100 ml. A randomised Latin square order of administration of trials was employed. Expired air samples for determination of Vo2, respiratory exchange ratio and rate of CHO oxidation were collected at 15-min intervals. Venous blood samples were obtained before and after exercise. Subjects drinking the isotonic glucose-electrolyte solution exercised longer (90.8 (12.4) min, mean (SEM] than on the control test (70.2 (8.3) min; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
Article
Four athletes developed water intoxication (hyponatremia) during endurance events lasting more than 7 h. The etiology of the condition appears to be voluntary hyperhydration with hypotonic solutions combined with moderate sweat sodium chloride losses. The reason why the fluid excess in these runners was not corrected by increased urinary losses is unknown. When advised to drink less during prolonged exercise, three of the athletes have subsequently completed prolonged endurance events uneventfully.
Article
1. The effect of osmolality and carbohydrate content on the rate of gastric emptying was assessed by using the double sampling gastric aspiration technique to measure the rate of gastric emptying of isoenergetic and isosmotic solutions of glucose and glucose polymer. Six healthy male subjects were each studied on four separate occasions using a test drink volume of 600 ml. 2. The half-emptying time (t1/2, mean +/- S.E.M.) for a dilute (40 g l-1) solution of glucose (LG, 230 mosmol kg-1) was 17 +/- 1 min. This was greater than that (14 +/- 1 min) for a glucose polymer solution with the same energy content (LP, 42 mosmol kg-1). A concentrated (188 g l-1) glucose polymer solution (HP, 237 mosmol kg-1) emptied faster (t1/2 = 64 +/- 8 min) than the corresponding isoenergetic glucose solution (HG, 1300 mosmol kg-1, t1/2 = 130 +/- 18 min). 3. The dilute (40 g l-1) glucose solution emptied faster than the concentrated (188 g l-1) glucose polymer solution with the same osmolality (LG, 230 mosmol kg-1; HP, 237 mosmol kg-1). 4. The two dilute solutions (40 g l-1) delivered a similar amount of carbohydrate to the small intestine, whereas the concentrated (188 g l-1) glucose polymer solution delivered a greater amount of carbohydrate at 20, 40 and 50 min than the isoenergetic glucose solution. 5. These results indicate that both osmolality and carbohydrate content influence gastric emptying of liquids in man, but the carbohydrate content appears to have greater influence than osmolality.(ABSTRACT TRUNCATED AT 250 WORDS)
Article
This study determined the effects of fluid and carbohydrate ingestion on performance, core temperature, and cardiovascular responses during intense exercise lasting 1 h. On four occasions, eight men cycled at 80 +/- 1% (+/- SEM) of VO2max for 50 min followed by a performance test. During exercise, they consumed either a large volume (1330 +/- 60 ml) of a 6% carbohydrate (79 +/- 4 g) solution or water or a small volume (200 +/- 10 ml) of a 40% maltodextrin (79 +/- 4 g) solution or water. These trials were pooled so the effects of fluid replacement (Large FR vs Small FR) and carbohydrate ingestion (CHO vs NO CHO) could be determined. Performance times were 6.5% faster during Large FR than Small FR and 6.3% faster during CHO than NO CHO (P < 0.05). At 50 min, heart rate was 4 +/- 1 b.min-1 lower and esophageal temperature was 0.33 +/- 0.04 degrees C lower during Large FR than Small FR (P < 0.05) but no differences occurred between CHO and NO CHO. In summary, Large FR slightly attenuates the increase in heart rate and core temperature which occurs during Small FR. Both fluid and carbohydrate ingestion equally improve cycling performance and their effects are additive.
Article
Six well-trained men (peak pulmonary oxygen uptake = 5.03 +/- 0.11 l/min) were studied during 2 h of exercise at 69 +/- 1% peak pulmonary oxygen uptake to examine the effect of carbohydrate (CHO) ingestion on glucose kinetics. Subjects ingested 250 ml of either a 10% glucose solution containing 6-[3H]glucose (CHO) or a sweet placebo every 15 min during exercise. Glucose kinetics were assessed by 6,6-[2H]glucose infusion corrected for gut-derived glucose in CHO. Plasma glucose was higher (P < 0.05) in CHO from 20 min. Total glucose appearance was higher in CHO due to glucose delivery from the gut (68 +/- 7 g), since hepatic glucose production was reduced by 51% (29 +/- 5 vs. 59 +/- 5 g). Glucose uptake was higher in CHO (96 +/- 7 vs. 60 +/- 6 g) with the ingested glucose supplying 67 +/- 4 g and, with the assumption that it was fully oxidized, accounted for 14 +/- 1% of total energy expenditure. In conclusion, CHO ingestion during prolonged exercise results in suppression of hepatic glucose production and increased glucose uptake. These effects appear to be mediated mainly by increased plasma glucose and insulin levels.
Article
A 17-year-old, nationally ranked, male tennis player (AH) had been experiencing heat cramps during tennis match play. His medical history and previous physical exams were unremarkable, and his in-office blood chemistry profiles were normal. On-court evaluation and an analysis of a 3-day dietary record revealed that AH's sweat rate was extensive (2.5 L.hr-1) and that his potential daily on-court sweat sodium losses (89.8 mmol.hr of play-1) could readily exceed his average daily intake of sodium (87.0-174.0 mmol.day-1). The combined effects of excessive and repeated fluid and sodium losses likely predisposed AH to heat cramps during play. AH was ultimately able to eliminate heat cramps during competition and training by increasing his daily dietary intake of sodium.
Article
Sodium and water loss during, and replacement after, exercise-induced volume depletion was investigated in six volunteers volume depleted by 1.89 +/- 0.17% (SD) of body mass by intermittent exercise in a warm, humid environment. Subjects exercised in a large, open plastic bag, allowing collection of all sweat secreted during exercise. For over 60 min beginning 40 min after the end of exercise, subjects ingested drinks containing 0, 25, 50, or 100 mmol/l sodium (trials 0, 25, 50, and 100) in a volume (ml) equivalent to 150% of the mass lost (g) by volume depletion. Body mass loss and sweat electrolyte (Na+, K+, and Cl-) loss were the same on each trial. The measured sweat sodium concentration was 49.2 +/- 18.5 mmol/l, and the total loss (63.9 +/- 38.7 mmol) was greater than that ingested on trials 0 and 25. Urine production over the 6-h recovery period was inversely related to the amount of sodium ingested. Subjects were in whole body negative sodium balance on trials 0 (-104 +/- 48 mmol) and 25 (-65 +/- 30 mmol) and essentially in balance on trial 50 (-13 +/- 29 mmol) but were in positive sodium balance on trial 100 (75 +/- 40 mmol). Only on trial 100 were subjects in positive fluid balance at the end of the study. There was a large urinary loss of potassium over the recovery period on trial 100, despite a negligible intake during volume repletion. These results confirm the importance of replacement of sodium as well as water for volume repletion after sweat loss. The sodium intake on trial 100 was appropriate for acute fluid balance restoration, but its consequences for potassium levels must be considered to be undesirable in terms of whole body electrolyte homeostasis for anything other than the short term.
Article
This study assessed whether replacing sweat losses with sodium-free fluid can lower the plasma sodium concentration and thereby precipitate the development of hyponatremia. Ten male endurance athletes participated in one 1-h exercise pretrial to estimate fluid needs and two 3-h experimental trials on a cycle ergometer at 55% of maximum O2 consumption at 34 degrees C and 65% relative humidity. In the experimental trials, fluid loss was replaced by distilled water (W) or a sodium-containing (18 mmol/l) sports drink, Gatorade (G). Six subjects did not complete 3 h in trial W, and four did not complete 3 h in trial G. The rate of change in plasma sodium concentration in all subjects, regardless of exercise time completed, was greater with W than with G (-2.48 +/- 2.25 vs. -0.86 +/- 1.61 mmol. l-1. h-1, P = 0.0198). One subject developed hyponatremia (plasma sodium 128 mmol/l) at exhaustion (2.5 h) in the W trial. A decrease in sodium concentration was correlated with decreased exercise time (R = 0.674; P = 0.022). A lower rate of urine production correlated with a greater rate of sodium decrease (R = -0. 478; P = 0.0447). Sweat production was not significantly correlated with plasma sodium reduction. The results show that decreased plasma sodium concentration can result from replacement of sweat losses with plain W, when sweat losses are large, and can precipitate the development of hyponatremia, particularly in individuals who have a decreased urine production during exercise. Exercise performance is also reduced with a decrease in plasma sodium concentration. We, therefore, recommend consumption of a sodium-containing beverage to compensate for large sweat losses incurred during exercise.
Article
For a person undertaking regular exercise, any fluid deficit that is incurred during one exercise session can potentially compromise the next exercise session if adequate fluid replacement does not occur. Fluid replacement after exercise can, therefore, frequently be thought of as hydration before the next exercise bout. The importance of ensuring euhydration before exercise and the potential benefits of temporary hyperhydration with sodium salts or glycerol solutions are also important issues. Post-exercise restoration of fluid balance after sweat-induced dehydration avoids the detrimental effects of a body water deficit on physiological function and subsequent exercise performance. For effective restoration of fluid balance, the consumption of a volume of fluid in excess of the sweat loss and replacement of electrolyte, particularly sodium, losses are essential. Intravenous fluid replacement after exercise has been investigated to a lesser extent and its role for fluid replacement in the dehydrated but otherwise well athlete remains equivocal.
Article
The amounts of water, carbohydrate and salt that athletes are advised to ingest during exercise are based upon their effectiveness in attenuating both fatigue as well as illness due to hyperthermia, dehydration or hyperhydration. When possible, fluid should be ingested at rates that most closely match sweating rate. When that is not possible or practical or sufficiently ergogenic, some athletes might tolerate body water losses amounting to 2% of body weight without significant risk to physical well-being or performance when the environment is cold (e.g. 5-10 degrees C) or temperate (e.g. 21-22 degrees C). However, when exercising in a hot environment ( > 30 degrees C), dehydration by 2% of body weight impairs absolute power production and predisposes individuals to heat injury. Fluid should not be ingested at rates in excess of sweating rate and thus body water and weight should not increase during exercise. Fatigue can be reduced by adding carbohydrate to the fluids consumed so that 30-60 g of rapidly absorbed carbohydrate are ingested throughout each hour of an athletic event. Furthermore, sodium should be included in fluids consumed during exercise lasting longer than 2 h or by individuals during any event that stimulates heavy sodium loss (more than 3-4 g of sodium). Athletes do not benefit by ingesting glycerol, amino acids or alleged precursors of neurotransmitter. Ingestion of other substances during exercise, with the possible exception of caffeine, is discouraged. Athletes will benefit the most by tailoring their individual needs for water, carbohydrate and salt to the specific challenges of their sport, especially considering the environment's impact on sweating and heat stress.
Article
Fluid balance and sweat electrolyte losses were measured in the players and substitutes engaged in an English Premier League Reserve competitive football match played at an ambient temperature of 6-8 degrees C (relative humidity 50-60%). Intake of water and/or sports drink and urine output were recorded, and sweat composition was estimated from absorbent swabs applied to 4 skin sites for the duration of the game. Body mass was recorded before and after the game. Data were obtained for 22 players (age 21 y, height 180 cm, mass 78 kg) and 9 substitutes (17 y, 181 cm, 72 kg). All were male. Two of the players were dismissed during the game, and none of the substitutes played any part in the game. Mean +/- SD sweat loss of players amounted to 1.68 +/- 0.40 L, and mean fluid intake was 0.84 +/- 0.47 L (n = 20), with no difference between teams. Corresponding values for substitutes, none of whom played in the match, were 0.40 +/- 0.24 L and 0.78 +/- 0.46 L (n = 9). Prematch urine osmolality was 678 +/- 344 mOsm/kg: 11 of the 31 players provided samples with an osmolality of more than 900 mOsm/kg. Sweat sodium concentration was 62 +/- 13 mmol/L, and total sweat sodium loss during the game was 2.4 +/- 0.8 g. These descriptive data show a large individual variability in hydration status, sweat losses, and drinking behaviors in a competitive football match played in a cool environment, highlighting the need for individualized assessment of hydration status to optimize fluid-replacement strategies.
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