Article

Omega 3 Chia Seed Loading as a Means of Carbohydrate Loading

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Abstract

The purpose of this study was to determine if Omega 3 Chia seed loading is a viable option for enhancing sports performance in events lasting >90 minutes and allow athletes to decrease their dietary intake of sugar while increasing their intake of Omega 3 fatty acids. It has been well documented that a high dietary carbohydrate (CHO) intake for several days before competition is known to increase muscle glycogen stores resulting in performance improvements in events lasting >90 minutes. This study compared performance testing results between 2 different CHO-loading treatments. The traditional CHO-loading treatment served as the control (100% cals from Gatorade). The Omega 3 Chia drink (50% of calories from Greens Plus Omega 3 Chia seeds, 50% Gatorade) served as the Omega 3 Chia loading drink. Both CHO-loading treatments were based on the subject's body weight and were thus isocaloric. Six highly trained male subjects V(O2)max 47.8-84.2 ml · kg(-1); mean (SD) of V(O2)max 70.3 ml · kg(-1) (13.3) performed a 1-hour run at ∼65% of their V(O2)max on a treadmill, followed by a 10k time trial on a track. There were 2 trials in a crossover counterbalanced repeated-measures design with a 2-week washout between testing sessions to allow the participants to recover from the intense exercise and any effects of the treatment. There was no statistical difference (p = 0.83) between Omega 3 Chia loading (mean 10k time = 37 minutes 49 seconds) and CHO loading (mean = 37 minutes 43 seconds). Under our conditions, Omega 3 Chia loading appears a viable option for enhancing performance for endurance events lasting >90 minutes and allows athletes to decrease their dietary intake of sugar while increasing their intake of Omega 3 fatty acids but offered no performance advantages.

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... Cardiovascular Decreased blood glucose [35][36][37] Increased Decreased body weight in ABCA1 R230C variant (MetS patients) [39] Decreased adiponectin in ABCA1 R230C variant (MetS patients) [39] Decreased weight in overweight adults [42] Decreased waist circumference in overweight adults [42] Integumentary Inhibition of total melanin production [43] Subjective improvement of pruritic skin [45] Improvement of lichen simplex chronicus [45] Improvement of prurigo nodularis [45] Improvement of skin capacitance [45] Musculoskeletal Increased endurance in 10 K athletes [47] Parker J et al. Therapeutic Perspectives on … Planta Med Postprandial glucose levels Additionally, the propensity toward overeating may be regulated with supplementation of chia. Lee et al. [35] found in one experiment that S. hispanica reduced the amount of postprandial blood glucose incremental area under the curve and reduced appetite on a subjective self-analysis by the subject. ...
... The primary argument by Nieman et al. [46] is that run time to exhaustion alter respiratory exchange ratio or counter elevations in cortisol and inflammatory outcome measures, which were not improved, although immediate post-run ALA levels did increase dramatically. Illian et al. [47] performed a strategic study in runners and concluded that chia oil glycogen loading could be used in place of omega-3 loading but ultimately produced no discernible benefits (see ▶ Table 1). The strategic benefit of using chia supplementation is that it allows for less sugar intake. ...
Article
The attraction of novel foods proceeds alongside epidemic cardiovascular disease, diabetes, obesity, and related risk factors. Dieticians have identified chia (Salvia hispanica) as a product with a catalog of potential health benefits relating to these detriments. Chia is currently consumed not only as seeds, but also as oil, which brings about similar effects. Chia seeds and chia seed oil are used mainly as a food commodity and the oil is also used popularly as a dietary ingredient used in various dietary supplements available in the U. S. market. Chia seed is rich in α-linolenic acid, the biological precursor to eicosapentaenoic acid, a polyunsaturated fatty acid, and docosahexaenoic acid. Because the body cannot synthesize α-linolenic acid, chia has a newfound and instrumental role in diet. However, the inconclusive nature of the scientific communityʼs understanding of its safety warrants further research and appropriate testing. The focus of this work is to summarize dietary health benefits of S. hispanica seed and oil to acknowledge concerns of adverse events from its ingestion, to assess current research in the field, and to highlight the importance of quality compendial standards to support safe use. To achieve this end, a large-scale literature search was partaken on the two well-known databases, PubMed and SciFinder. Hundreds of articles detailing such benefits as decreased blood glucose, decreased waist circumference and weight in overweight adults, and improvements in pruritic skin and endurance in distance runners have been recorded. These benefits must be considered within the appropriate circumstances.
... In spite of chia's well-known properties of an antioxidant and its healthy fatty acid profile, many people are still unaware of its benefits. The argentine economy is very much depending upon chia seed production as it has a 24% contribution in the agricultural industry [58][59] . In the 2008 report, it is mentioned that Argentina contributed approx. ...
Article
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Salvia hispanica L. Well known as chia is gaining popularity day by day due to its nutritional value. This plant is native to Mexico, belonging to family Labiatae / Laminacea, and it was used as a superfood from ancient times. Chia is valued more due to its oil content as it consists of omega-3-alpha linolenic acid in higher amount along with various types of other nutrients, e.g., proteins, dietary fibers, antioxidants, etc. which is very beneficial to keep a person healthy and also it helps in prevention of many diseases like CVS, diabetes, obesity cancer and also it gives strength to our immune system. In the past few decades, we have noticed a certain growth in the market value of chia, and it is increasing day by day, not in a particular area or region but around the whole globe. In this paper, we have discussed all the important characteristics of chia (from its morphological characters to its pharmacological properties along with nutritional values and its today's marketing value) by collecting different kinds of literature and surveys.
... Furthermore, only 3.1% of para-athletes correctly answered the question about the percentage of dietary carbohydrate needed for glycogen (carbohydrate) loading. Glycogen (carbohydrate) loading is a basic knowledge in sports conditioning as a means of increasing intramuscular glycogen stores [73], and improve performance [74,75]. Thus, even para-athletes at a high competition level do not have basic knowledge of sports nutrition, and conversely, there is room for improvement in competitive performance through the transition of sports nutrition knowledge to them. ...
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Limited information exists on dietary practices in para-athletes. The aim of this study was to clarify the actual situation of para-athletes’ dietary practice and to sort out the factors (i.e., eating perception, nutrition knowledge, and body image), that may hinder their dietary practices, and explored the practical challenges in nutritional support and improving nutrition knowledge for para-athletes. Thirty-two Japanese para-athletes (22 men) and 45 collegiate student athletes without disabilities (27 men) participated in the online survey. The questionnaire included demographic characteristics, eating perception, dietary practices, and nutrition knowledge. The Japanese version of the body appreciation scale was used to determine their body image. Para-athletes who answered that they knew their ideal amount and way of eating showed significantly higher body image scores (r = 0.604, p < 0.001). However, mean score for nutrition knowledge of para-athletes were significantly lower than collegiate student athletes (19.4 ± 6.8 vs. 24.2 ± 6.1 points, p = 0.001). Both groups did not identify a dietitian as the source of nutrition information or receiving their nutrition advice. The results indicate para-athletes have unique eating perceptions and inadequate nutrition knowledge. Future interventions are needed to examine nutritional supports and education in relation to the role of dietitians.
... Chia seed (Salvia hispanica L.) is an oilseed native to southern Mexico and northern Guatemala, and is a rich source of ALA, containing 4.4 g ALA (57% of total fat) per 25 g serving [16][17][18][19][20]. One previous study showed that a mixture of chia seeds and a 6% carbohydrate sports beverage supported 10-km running performance (following a 1-h moderate run) to the same level as an isocaloric volume of the 6% carbohydrate sports beverage alone [21]. Although not measured, these data imply that ALA β-oxidation provided energy to support high intensity running performance. ...
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Runners (n = 24) reported to the laboratory in an overnight fasted state at 8:00 am on two occasions separated by at least two weeks. After providing a blood sample at 8:00 am, subjects ingested 0.5 liters flavored water alone or 0.5 liters water with 7 kcal kg-1 chia seed oil (random order), provided another blood sample at 8:30 am, and then started running to exhaustion (~70% VO2max). Additional blood samples were collected immediately post- and 1-h post-exercise. Despite elevations in plasma alpha-linolenic acid (ALA) during the chia seed oil (337%) versus water trial (35%) (70.8 ± 8.6, 20.3 ± 1.8 μg mL-1, respectively, p < 0.001), run time to exhaustion did not differ between trials (1.86 ± 0.10, 1.91 ± 0.13 h, p = 0.577, respectively). No trial differences were found for respiratory exchange ratio (RER) (0.92 ± 0.01), oxygen consumption, ventilation, ratings of perceived exertion (RPE), and plasma glucose and blood lactate. Significant post-run increases were measured for total leukocyte counts, plasma cortisol, and plasma cytokines (Interleukin-6 (IL-6), Interleukin-8 (IL-8), Interleukin-10 (IL-10), and Tumor necrosis factors-α (TNF-α)), with no trial differences. Chia seed oil supplementation compared to water alone in overnight fasted runners before and during prolonged, intensive running caused an elevation in plasma ALA, but did not enhance run time to exhaustion, alter RER, or counter elevations in cortisol and inflammatory outcome measures.
... Chia seed (Salvia hispanica L.) is an oilseed native to southern Mexico and northern Guatemala, and is a rich source of ALA, containing 4.4 g ALA (57% of total fat) per 25 g serving [16][17][18][19][20]. One previous study showed that a mixture of chia seeds and a 6% carbohydrate sports beverage supported 10-km running performance (following a 1-h moderate run) to the same level as an isocaloric volume of the 6% carbohydrate sports beverage alone [21]. Although not measured, these data imply that ALA β-oxidation provided energy to support high intensity running performance. ...
... High dietary carbohydrate intake by athletes for several days before competition is known to increase muscle glycogen stores resulting in performance improvements in events lasting longer than 90 min. Illian et al. (2011) compared two high dietary carbohydrates, the traditional Gatorade (a sports drink) and a chia seed-based drink for sports performance augmentation. After treadmill and track running trials of six subjects, no difference was observed in the recovery from the intense exercise. ...
Chapter
Chia seed (Salvia hispanica) is an emerging plant-derived nutraceutical. With a balanced composition of dietary fiber, proteins, ω-3 fatty acids, antioxidants, vitamins and essential minerals, this seed has attracted the attention of nutritionists. Rich in α-linolenic acid, it is credited to be instrumental in cardiac and hepatic protection. Also, the abundance of dietary fibres is recognized to confer digestive benefits, whereas the proteins augment physical endurance. Further, antidiabetic and anticancer properties are being disclosed. Improvement of meat quality by feeding chia diet to the animals is another potential implication. Though a relatively newbie in the functional food sector, this seed is expected to boom in popularity within no time. In this regard, an updated account on the health potentials of this emerging ‘superfood’ has been furnished. This chapter is expected to play role in revival of this erstwhile source of sustenance into a sustainable food.
... There are different experimental trials where researches found beneficial effects of the daily intake of 35À37 g of ground chia can exert a blood pressure reduction (Toscano et al., 2014;Vuksan et al., 2007). For the athletes that require endurance, the consumption of chia seeds provides ω-3 fatty acids (Illian, Casey, & Bishop, 2011). It has been hypothesized that dietary fiber and ω-3 fatty acids are involved in losing weight; chia mucilage can absorb a high amount of water, forming a large bolus that passes into the stomach evoking great satiety which may reduce consumption of more food. ...
Chapter
Salvia hispanica L. commonly known as chia is an ancient food that provides a balanced amount of nutrients composed of insoluble fiber, high ω-3/-6 fatty acids, proteins with an excellent quality of amino acids, high content of antioxidants, and minerals. In first instance, chia seeds contain a coat mucilage that covers completely all seed nutrients and is involved in water retention in consumers. The seed is a valuable source of one of the most important ω-3 fatty acids, α-linoleic, the storage proteins are composed mainly by globulin, followed by albumin, prolamin and glutelin fractions; and they are encrypted in their primary sequences of essential amino acids. Rosmarinic, caffeic and gallic acids are the main phenolic compounds. Nutritionists, researchers and industry have paid attention to chia for its outstanding benefits. Chia is now recognized as a “seed for the first 21st century” that confers invaluable nutraceutical benefits such as antihypertensive and antioxidant functions. The seed compounds may be improved and modified by genome edition technologies to obtain better nutraceutical attributes for health and food industry. Chia can be crowned as the new golden and super seed with excellent benefits for human health.
... Estado de México, Jalisco, Nayarit and Sinaloa), Guatemala, Nicaragua and Honduras ( Figure 1). Chia was an important food source for the Aztecs, who during in the wars of conquest that lasted several days, their warriors as such as the informants who traveled great distances had as food source only small amounts of this oilseed [4,29]. But chia not only was used for the Aztecs, and in the Lienzo de Tlaxcala (Tlaxcaltecs war book) which is also known as Yaotlacuiloli, [30] there are evidences that in 1531 chia was cultivated in the South of Sinaloa; at least so it reflects the picture painted by the Tlaxcaltecs warriors that accompanied to Nuño of Guzman and its Spanish warriors in the conquest of Chiyametlan (today Chametla) that in Nahua language means place where there is a lot of chia. ...
Article
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Chia Crop (Salvia hispanica l.): its History and Importance as a Source of Polyunsaturated Fatty Acids Omega-3 Around the World: a Review Anacleto Sosa1,5, Guadalupe Ruiz2, Jat Rana3, Gerardo Gordillo1, Heather West4, Maneesh Sharma4, Xiaozhong Liu4. Raul Rene Robles de la Torre5 1Nutrilite S de RL de CV. Av. México #8. Rancho El Petacal, Municipio de Tolimán Jalisco, México. CP 49750. Phone 01 341 41 178 78 ext. 112. 2Instituto Tecnológico Superior de Tamazula de Gordiano Jalisco, México. 3 Amway Corporation, 7575 Fulton St. East Bldg. 50-2D, Ada Michigan 49355. Phone 616-787-1409. 4Amway Corporation, Beach Boulevard, # 5600, Buena Park California, USA. CP 90621. Phone 714-5 62-48800. 5Centro de Biotecnología Aplicada (CIBA-IPN). IBA-Tlaxcala, Hacienda San Juan Molino Km 15 Carretera Estatal Tecuexcomac-Tepetitla, Las Palomas CP 90700. Email: anacleto.sosa@amway.com Abstract Since 5,500 years ago, chia (Salvia hispanica L.) crop is used as food in Mexico, and today is considered one of the most important sources of polyunsaturated fatty acids (PUFAs) of omega-3 (ω3) for the man. This specie has a fascinating history that is little known; hence, the main objective of this work is to contribute to know its history and importance as a crop and source of PUFAs ω3 on the world. Chia along corn, bean and amaranths were key on feeding of México; however, after the Spanish conquest the restrictions on its use by around of 260 years led to the chia production almost disappeared, this because the traditional use as a food and medicine was not completely transmitted in at least six generations. After the independence of Mexico, the chia to overcome the oblivion of almost 180 years and it was able to become the 90s decade because some farmers of Acatic Jalisco retained the tradition of their use as crop. Because the chia crop presents agronomic rusticity and high content of PUFAs ω3, it has become one of the most important functional crops and currently are cultivated 370, 000 has of chia in several agricultural regions of the world. The integration into modern agriculture of chia is ongoing and considering that in the next years their demand will continue increasing is evident that the chia after a lethargy of almost 500 years in the future could be destined to be the Sleeping Beauty of the nutraceutical crops on wide world. Key words: chia, Omega 3, fatty acids, Nutrition.
... Estado de México, Jalisco, Nayarit and Sinaloa), Guatemala, Nicaragua and Honduras ( Figure 1). Chia was an important food source for the Aztecs, who during in the wars of conquest that lasted several days, their warriors as such as the informants who traveled great distances had as food source only small amounts of this oilseed [4,29]. But chia not only was used for the Aztecs, and in the Lienzo de Tlaxcala (Tlaxcaltecs war book) which is also known as Yaotlacuiloli, [30] there are evidences that in 1531 chia was cultivated in the South of Sinaloa; at least so it reflects the picture painted by the Tlaxcaltecs warriors that accompanied to Nuño of Guzman and its Spanish warriors in the conquest of Chiyametlan (today Chametla) that in Nahua language means place where there is a lot of chia. ...
Article
Full-text available
Abstract Since 5,500 years ago, chia (Salvia hispanica L.) crop is used as food in Mexico, and today is considered one of the most important sources of polyunsaturated fatty acids (PUFAs) of omega-3 (ω3) for the man. This specie has a fascinating history that is little known; hence, the main objective of this work is to contribute to know its history and importance as a crop and source of PUFAs ω3 on the world. Chia along corn, bean and amaranths were key on feeding of México; however, after the Spanish conquest the restrictions on its use by around of 260 years led to the chia production almost disappeared, this because the traditional use as a food and medicine was not completely transmitted in at least six generations. After the independence of Mexico, the chia to overcome the oblivion of almost 180 years and it was able to become the 90s decade because some farmers of Acatic Jalisco retained the tradition of their use as crop. Because the chia crop presents agronomic rusticity and high content of PUFAs ω3, it has become one of the most important functional crops and currently are cultivated 370, 000 has of chia in several agricultural regions of the world. The integration into modern agriculture of chia is ongoing and considering that in the next years their demand will continue increasing is evident that the chia after a lethargy of almost 500 years in the future could be destined to be the Sleeping Beauty of the nutraceutical crops on wide world.
... and hs-CRP levels in chia group -No difference of effects on glycaemic control and blood pressure Ho et al., 2013 Postprandial (15., 30., 45., 60., 90., 120. mins) 13 healthy individuals 0, 7, 15 or 25 g whole or milled chia seed in 50 g bread -Decrease in blood glucose levels in a dose dependent manner whether it is milled or whole chia Chia seed supplement for athletes that perform more than 90 minutes can be used due to chia seed's omega-3 fatty acid, fiber, protein and antioxidant components (Illian et al., 2011). On the other hand, 7 kcal/kg chia oil extract supplementation to the water of runners has no effect on performance instead an increase in plasma ALA levels (Nieman et al., 2015). ...
Article
Chia seed (Salvia hispanica L.) is getting attention with its high polyunsaturated fatty acid, dietary fiber content and antioxidant capacity in recent years. It is considered as a functional food or ingredient because of being a natural source of some bioactive substances such as polyphenol compounds, dietary fiber, and omega-3 fatty acid. In human consumption, it can be used alone as whole chia seed or for the preparation especially bakery products. It has high antioxidant properties and angiotensin converting enzyme inhibitory effects in vitro. It is considered that chia prevents from cardiovascular diseases, diabetes mellitus and obesity with its high omega- 3 fatty acid and dietary fiber content. Furthermore previous studies demonstrated the fiber and protein fractions of chia seed can be used in food industry for many purposes. In this review, nutritional value of chia, usage in food industry and effects on health is examined.
... The applicants provided eight articles on human studies (Nieman et al., 2009Vuksan et al., 2010Vuksan et al., , 2017aIllian et al., 2011;Guevara-Cruz et al., 2012;Jin et al., 2012;Ho et al., 2013) and three reviews (Ulbricht et al., 2009;Ali et al., 2012;Teoh et al., 2018). EFSA retrieved six additional human studies in literature search (Brissette et al., 2013;Toscano et al., 2014Toscano et al., , 2015Nieman et al., 2015;Ayaz et al., 2017;Vuksan et al., 2017b) and three review articles (De Souza Ferreira et al., 2015;Parker et al., 2018;Grancieri et al., 2019). ...
Article
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Following a request from the European Commission, the EFSA Panel on Nutrition, Novel foods and Food Allergens (NDA) was asked to deliver an opinion on overall safety assessment for chia seeds (Salvia hispanica L.) as a novel food (NF) pursuant to Regulation (EU) 2015/2283 in the light of the increasing dietary intake from the growing number of authorised uses in recent years. The safety assessment of this NF is based on data supplied in seven applications, previous safety assessments of chia seeds and information retrieved from an extensive literature search done by EFSA. Since none of the applications addressed the possible formation of process contaminants, the present assessment is limited to those proposed extended uses which do not raise safety concerns regarding the formation of such contaminants. These include the use of whole and ground chia seeds added to chocolate, fruit spreads, fruit desserts, mixed fruit with coconut milk in twin pot, fruit-preparations to underlay a dairy product, fruit-preparations to be mixed with dairy products, confectionary (excluding chewing gums), dairy products and analogues, edible ices, fruit and vegetables products, non-alcoholic beverages and compotes from fruit and/or vegetables and/or with cereals. In addition, this assessment also concerns uses of chia seeds without specific restrictions and precautions regarding their use levels in other foods which usually do not include heat treatment during processing and cooking. Apart from allergenicity, the Panel did not identify any hazard which causes safety concerns. Lacking the basis and need to establish safe maximum intake levels for chia seeds, no exposure assessment was conducted. The Panel concludes that chia seeds are safe under the assessed conditions of use. © 2019 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.
... [ 24] In autumn 2018, Slovenia experienced a fast Chia outbreak. Mainly, the occurrence of these species was on gravel bars, stretching to about 2,000 square kilometers. ...
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Chia (Salvia hispanica L.) is a small seed that comes from an annual herbaceous plant, Salvia hispanica L. In recent years, usage of Chia seeds has tremendously grown due to their high nutritional and medicinal values. Chia was cultivated by Mesopotamian cultures, but then disappeared for centuries until the middle of the 20th century, when it was rediscovered. Chia seeds contain healthy ω-3 fatty acids, polyunsaturated fatty acids, dietary fiber, proteins, vitamins, and some minerals. Besides this, the seeds are an excellent source of polyphenols and antioxidants, such as caffeic acid, rosmarinic acid, myricetin, quercetin, and others. Today, chia has been analyzed in different areas of research. Researches around the world have been investigating the benefits of chia seeds in the medicinal, pharmaceutical, and food industry. Chia oil is today one of the most valuable oils on the market. Different extraction methods have been used to produce the oil. In the present study, an extensive overview of the chemical composition, nutritional properties, and antioxidant and antimicrobial activities, along with extraction methods used to produce chia oil, will be discussed.
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RESUMO: A cultura da chia (Salvia hispanica L.) pertence à família das Lamiaceas, originária da região que compreende o centro-oeste do México até o norte da Guatemala. Grande fonte de energia, era um dos principais alimentos dos Astecas no período Pré-Colombiano. A semente é rica em ácidos graxos insaturados (ômega-3 e ômega-6) fibras, proteínas, carboidratos, sais minerais, antioxidantes e vitaminas. As sementes de chia produzem uma grande quantidade de mucilagem quando embebidas em água, podendo ser consumidas in natura, na forma de farinha ou óleo. A planta é cultivada principalmente em regiões de clima tropical e subtropical, situadas entre 0 a 2600 m de altitude, tolera condições de salinidade e seca, entretanto não resiste a geadas. Entre os países que se destacam no cultivo estão a Austrália, Bolívia, Colômbia, Guatemala, México, Perú e Argentina. O cultivo no Brasil ainda é recente, e por esse motivo são poucas as informações contidas na literatura em relação às práticas, exigências nutricionais e manejo da cultura nos climas e solos Brasileiros. Neste contexto, serão abordados os aspectos relacionados às características e classificação da cultura, composição química e germinação das sementes, práticas e manejo da cultura e também as suas formas de utilização e comercialização. ABSTRACT: The chia plant (Salvia hispanica L.) belongs to Lamiacea family, from the region comprising the Noth of Midwest Mexico to Guatemala. Major source of energy, this culture was an important nutrition source to Aztec civilizacion in pré-Columbian period. The seed is rich in unsaturated fatty acids (omega-3 and omega-6), fiber, protein, carbohydrates, minerals, antioxidants and vitamins. Chia seeds produce large amounts of mucilage when soaked in water and can be eaten raw, in the form of meal or oil. The chia cultivation is mainly in tropical and subtropical climate, situated between 0-2600 m altitude, tolerates drought and salinity conditions, however does not withstand frost. Among the countries that stand out are growing in Australia, Bolivia, Colombia, Guatemala, Mexico, Peru and Argentina. The cultivation in Brazil is still recent, and therefore there is little information in the literature about the practices, nutritional requirements and crop management in Brazilian soils and climates. In this context, issues related to the characteristics and classification of culture, chemical composition, and germination of seeds, and crop management practices and also their ways of using and marketing will be addressed.
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This book introduces some emerging functional foods that are natural resources with tremendous promise as nutraceuticals and pharmaceuticals. The author considers biodiversity and bioprospecting as a response to food security issues, drug-resistance, nutrition-poor diets and other problems, exploring the prospects of several under-utilized nutrients and bioactive repositories. Readers will discover biochemical makeups, validated health benefits, explanations of underlying mechanisms, hurdles in the path of popularity and promotion strategies. Chapters explore particular plants, seeds and fruits including the strawberry guava, opuntia fruits, the Carissa genus, grape seeds, quinoa and the milk thistle (Silybum), amongst others. They are considered as food sources where possible and from the perspective of the roles they can play in complementary and alternative medicine, such as in wound healing, antimicrobial activity, gastroprotective activity in treatment of cancers and as natural antioxidant sources. This rich compilation holds plausible solutions to a range of current issues and it endorses the much-needed goal of sustainability in terms of diet and drugs. It paves the path for further research and development on hitherto obscure natural resources. Scientists working in the area of food development, phytochemical and antioxidant analysis, bioprospecting of low-profile foods and in complementary and alternative medicine will find this work particularly valuable. It will also be of interest to the general reader with an interest in food science, food security, phytochemicals and functional food studies.
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We examined the time course of metabolic adaptations to 15 days of a high-fat diet (HFD). Sixteen endurance-trained cyclists were assigned randomly to a control (CON) group, who consumed their habitual diet (30% ± 8% mJ fat), or a HFD group, who consumed a high-fat isocaloric diet (69% ± 1% mJ fat). At 5-day intervals, the subjects underwent an oral glucose tolerance test (OGTT); on the next day, they performed a 2.5-hour constant-load ride at 70% peak oxygen consumption (VO2peak), followed by a simulated 40-km cycling time-trial while ingesting a 10% 14C-glucose + 3.44% medium-chain triglyceride (MCT) emulsion at a rate of 600 mL/h. In the OGTT, plasma glucose concentrations at 30 minutes increased significantly after 5 days of the HFD and remained elevated at days 10 and 15 versus the levels measured prior to the HFD (P < .05). The activity of carnitine acyltransferase (CAT) in biopsies of the vastus lateralis muscle also increased from 0.45 to 0.54 μmol/g/min over days 0 to 10 of the HFD (P < .01) without any change in citrate synthase (CS) or 3-hydroxyacyl-coenzyme A dehydrogenase (3-HAD) activities. Changes in glucose tolerance and CAT activity were associated with a shift from carbohydrate (CHO) to fat oxidation during exercise (P < .001), which occurred within 5 to 10 days of the HFD. During the constant-load ride, the calculated oxidation of muscle glycogen was reduced from 1.5 to 1.0 g/min (P < .001) after 15 days of the HFD. Ingestion of a HFD for as little as 5 to 10 days significantly altered substrate utilization during submaximal exercise but did not attenuate the 40-km time-trial performance.
Article
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For 5 days, eight well-trained cyclists consumed a random order of a high-carbohydrate (CHO) diet (9.6 g. kg(-1). day(-1) CHO, 0.7 g. kg(-1). day(-1) fat; HCHO) or an isoenergetic high-fat diet (2.4 g. kg(-1). day(-1) CHO, 4 g. kg(-1). day(-1) fat; Fat-adapt) while undertaking supervised training. On day 6, subjects ingested high CHO and rested before performance testing on day 7 [2 h cycling at 70% maximal O(2) consumption (SS) + 7 kJ/kg time trial (TT)]. With Fat-adapt, 5 days of high-fat diet reduced respiratory exchange ratio (RER) during cycling at 70% maximal O(2) consumption; this was partially restored by 1 day of high CHO [0.90 +/- 0.01 vs. 0.82 +/- 0.01 (P < 0.05) vs. 0.87 +/- 0.01 (P < 0.05), for day 1, day 6, and day 7, respectively]. Corresponding RER values on HCHO trial were [0. 91 +/- 0.01 vs. 0.88 +/- 0.01 (P < 0.05) vs. 0.93 +/- 0.01 (P < 0.05)]. During SS, estimated fat oxidation increased [94 +/- 6 vs. 61 +/- 5 g (P < 0.05)], whereas CHO oxidation decreased [271 +/- 16 vs. 342 +/- 14 g (P < 0.05)] for Fat-adapt compared with HCHO. Tracer-derived estimates of plasma glucose uptake revealed no differences between treatments, suggesting muscle glycogen sparing accounted for reduced CHO oxidation. Direct assessment of muscle glycogen utilization showed a similar order of sparing (260 +/- 26 vs. 360 +/- 43 mmol/kg dry wt; P = 0.06). TT performance was 30.73 +/- 1.12 vs. 34.17 +/- 2.48 min for Fat-adapt and HCHO (P = 0.21). These data show significant metabolic adaptations with a brief period of high-fat intake, which persist even after restoration of CHO availability. However, there was no evidence of a clear benefit of fat adaptation to cycling performance.
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Prior to endurance competition, many endurance athletes participate in a carbohydrate loading regimen in order to help delay the onset of fatigue. The "classic" regimen generally includes an intense glycogen depleting training period of approximately two days followed by a glycogen loading period for 3-4 days, ingesting approximately 60-70% of total energy intake as carbohydrates, while the newer method does not consist of an intense glycogen depletion protocol. However, recent evidence has indicated that glycogen loading does not occur in the same manner for males and females, thus affecting performance. The scope of this literature review will include a brief description of the role of estradiol in relation to metabolism and gender differences seen in carbohydrate metabolism and loading.
Article
We examined the time course of metabolic adaptations to 15 days of a high-fat diet (HFD). Sixteen endurance-trained cyclists were assigned randomly to a control (CON) group, who consumed their habitual diet (30% ± 8% mJ fat), or a HFD group, who consumed a high-fat isocaloric diet (69% ± 1% mJ fat). At 5-day intervals, the subjects underwent an oral glucose tolerance test (OGTT); on the next day, they performed a 2.5-hour constant- load ride at 70% peak oxygen consumption (VO(2peak)), followed by a simulated 40-km cycling time-trial while ingesting a 10% 14C-glucose + 3.44% medium- chain triglyceride (MCT) emulsion at a rate of 600 mL/h. In the OGTT, plasma glucose concentrations at 30 minutes increased significantly after 5 days of the HFD and remained elevated at days 10 and 15 versus the levels measured prior to the HFD (P < .05). The activity of carnitine acyltransferase (CAT) in biopsies of the vastus lateralis muscle also increased from 0.45 to 0.54 μmol/g/min over days 0 to 10 of the HFD (P < .01) without any change in citrate synthase (CS) or 3-hydroxyacyl-coenzyme A dehydrogenase (3-HAD) activities. Changes in glucose tolerance and CAT activity were associated with a shift from carbohydrate (CHO) to fat oxidation during exercise (P < .001), which occurred within 5 to 10 days of the HFD. During the constant- load ride, the calculated oxidation of muscle glycogen was reduced from 1.5 to 1.0 g/min (P < .001) after 15 days of the HFD. Ingestion of a HFD for as little as 5 to 10 days significantly altered substrate utilization during submaximal exercise but did not attenuate the 40-km time-trial performance.
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The muscle glycogen content of the quadriceps femoris muscle was determined in 9 healthy subjects with the aid of the needle biopsy technique. The glycogen content could be varied in the individual subjects by instituting different diets after exhaustion of the glycogen store by hard exercise. Thus, the glycogen content after a fat ± protein (P) and a carbohydrate-rich (C) diet varied maximally from 0.6 g/100g muscle to 4.7 g. In all subjects, the glycogen content after the C diet was higher than the normal range for muscle glycogen, determined after the mixed (M) diet. After each diet period, the subjects worked on a bicycle ergometer at a work load corresponding to 75 per cent of their maximal O2 uptake, to complete exhaustion. The average work time was 59, 126 and 189 min after diets P, M and C, and a good correlation was noted between work time and the initial muscle glycogen content. The total carbohydrate utilization during the work periods (54–798 g) was well correlated to the decrease in glycogen content. It is therefore concluded that the glycogen content of the working muscle is a determinant for the capacity to perform long-term heavy exercise. Moreover, it has been shown that the glycogen content and, consequently, the long-term work capacity can be appreciably varied by instituting different diets after glycogen depletion.
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We determined the effect of fat adaptation on metabolism and performance during 5 h of cycling in seven competitive athletes who consumed a standard carbohydrate (CHO) diet for 1 day and then either a high-CHO diet (11 g {middle dot} kg[-]1 {middle dot} day[-]1 CHO, 1 g {middle dot} kg[-]1 {middle dot} day[-]1 fat; HCHO) or an isoenergetic high-fat diet (2.6 g {middle dot} kg[-]1 {middle dot} day[-]1 CHO, 4.6 g {middle dot} kg[-]1 {middle dot} day[-]1 fat; fat-adapt) for 6 days. On day 8, subjects consumed a high-CHO diet and rested. On day 9, subjects consumed a preexercise meal and then cycled for 4 h at 65% peak O2 uptake, followed by a 1-h time trial (TT). Compared with baseline, 6 days of fat-adapt reduced respiratory exchange ratio (RER) with cycling at 65% peak O2 uptake [0.78 {+/-} 0.01 (SE) vs. 0.85 {+/-} 0.02; P < 0.05]. However, RER was restored by 1 day of high-CHO diet, preexercise meal, and CHO ingestion (0.88 {+/-} 0.01; P < 0.05). RER was higher after HCHO than fat-adapt (0.85 {+/-} 0.01, 0.89 {+/-} 0.01, and 0.93 {+/-} 0.01 for days 2, 8, and 9, respectively; P < 0.05). Fat oxidation during the 4-h ride was greater (171 {+/-} 32 vs. 119 {+/-} 38 g; P < 0.05) and CHO oxidation lower (597 {+/-} 41 vs. 719 {+/-} 46 g; P < 0.05) after fat-adapt. Power output was 11% higher during the TT after fat-adapt than after HCHO (312 {+/-} 15 vs. 279 {+/-} 20 W; P = 0.11). In conclusion, compared with a high-CHO diet, fat oxidation during exercise increased after fat-adapt and remained elevated above baseline even after 1 day of a high-CHO diet and increased CHO availability. However, this study failed to detect a significant benefit of fat adaptation to performance of a 1-h TT undertaken after 4 h of cycling.
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Men with regular physical training habits voluntarily increased their dietary fat intake from 43 to 54% of energy (E%) for four weeks. This was followed by a low-fat (29 E%), high-carbohydrate diet for another four weeks. During the high-fat diet period, the muscle lipoprotein lipase activity (LPLA) increased from 59 +/- 8 to 106 +/- 12 mU/g (mean +/- SE) (P less than 0.05). After the high-carbohydrate diet, LPLA was 57 +/- 16 mU/g, and unchanged relative to the pre-trial value. The triglyceride content in m. vastus lateralis increased from 30 +/- 4 to 47 +/- 9 mmol/kg d.w. (P less than 0.05; mean +/- SE) following the high-fat diet and to 41 +/- 8 following the high-carbohydrate diet. Neither of the diets affected the serum triglyceride and insulin concentrations, nor glucose, glycerol, beta-hydroxybutyrate, citrate and lactate levels in the blood. Nor did they alter enzyme activities in muscle used as markers for the oxidative (citrate synthase, beta-hydroxy-acyl CoA dehydrogenase) and glycolytic (glyceraldehyde phosphate dehydrogenase, lactate dehydrogenase) capacity. It is concluded that one month's adaptation to a high-fat diet results in increased muscle-LPL activity indicating a higher capacity for uptake of fatty acids from circulating serum triglycerides into the muscle cell in association with a greater capacity for triglyceride storage in the muscle. Under these conditions serum triglycerides were not decreased despite the increased muscle LPLA, and serum insulin variations could not explain the change in muscle LPLA.(ABSTRACT TRUNCATED AT 250 WORDS)
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In order to study how the diet may influence sympatho-adrenal activity during exercise, 7 subjects were examined at rest and during submaximal exercise (25 min at 65% of VO2 max) on two occasions. The first occasion was preceded by 5 days on a carbohydrate poor diet (5% carbohydrate, 72% fat and 23% protein) and the second one by 5 days on a carbohydrate rich diet (78% carbohydrate, 8% fat and 14% protein) with the same energy content. Oxygen uptake, respiratory exchange ratio (R), heart rate and arterial plasma concentrations of adrenaline, noradrenaline, dopamine, insulin, glucose, lactate, free fatty acids (FFA), glycerol and beta-hydroxybutyrate were measured at rest and during exercise. Oxygen uptake and heart rate during exercise were higher and R was lower after the carbohydrate poor than after the carbohydrate rich diet. During exercise the arterial plasma concentrations of FFA, glycerol and beta-hydroxybutyrate were higher after the carbohydrate poor than after the carbohydrate rich diet whereas concentrations of insulin and lactate were lower. At rest arterial plasma noradrenaline and adrenaline levels were similar on the two diets (0.70 +/- 0.31 nM noradrenaline and 0.35 +/- 0.32 nM adrenaline one the carbohydrate rich diet, mean values +/- SD). Exercise induced increases in noradrenaline were more pronounced after the carbohydrate poor than after the carbohydrate rich diet (12.42 +/- 3.41 vs. 7.45 +/- 2.68 at 25 min of exercise, p less than 0.001). A similar, although more variable accentuation of exercise induced increases in adrenaline was found. It is concluded that, when compared to a carbohydrate rich diet, a carbohydrate poor diet increases the relative contribution of fat to oxidative metabolism and increases the sympatho-adrenal response to exercise. Stimulation of lipolysis by sympatho-adrenal mechanisms might be of importance for the substrate availability when carbohydrate intake in low.
Article
To study the effect of chronic ketosis on exercise performance in endurance-trained humans, five well-trained cyclists were fed a eucaloric balanced diet (EBD) for one week providing 35-50 kcal/kg/d, 1.75 g protein/kg/d and the remainder of kilocalories as two-thirds carbohydrate (CHO) and one-third fat. This was followed by four weeks of a eucaloric ketogenic diet (EKD), isocaloric and isonitrogenous with the EBD but providing less than 20 g CHO daily. Both diets were appropriately supplemented to meet the recommended daily allowances for vitamins and minerals. Pedal ergometer testing of maximal oxygen uptake (VO2max) was unchanged between the control week (EBD-1) and week 3 of the ketogenic diet (EKD-3). The mean ergometer endurance time for continuous exercise to exhaustion (ENDUR) at 62%-64% of VO2max was 147 minutes at EBD-1 and 151 minutes at EKD-4. The ENDUR steady-state RQ dropped from 0.83 to 0.72 (P less than 0.01) from EBD-1 to EKD-4. In agreement with this were a three-fold drop in glucose oxidation (from 15.1 to 5.1 mg/kg/min, P less than 0.05) and a four-fold reduction in muscle glycogen use (0.61 to 0.13 mmol/kg/min, P less than 0.01). Neither clinical nor biochemical evidence of hypoglycemia was observed during ENDUR at EKD-4. These results indicate that aerobic endurance exercise by well-trained cyclists was not compromised by four weeks of ketosis. This was accomplished by a dramatic physiologic adaptation that conserved limited carbohydrate stores (both glucose and muscle glycogen) and made fat the predominant muscle substrate at this submaximal power level.
Article
This study examined the effect of three exercise-diet regimens on muscle glycogen supercompensation and subsequent performance during a 20.9-km run. A diet containing 15% carbohydrate (CHO,L), 50% CHO (M), or 70% (CHO (H) was arranged in three trials as follows: trial A = 3 days L, 3 days H; trial B = 3 days M, 3 days H; trial C = 6 days M. For each trial a 5-day depletion-taper exercise sequence was conducted on the treadmill at 73% VO2 max. The runs were 90, 40, 40, 20, and 20 min, respectively. A day of rest preceded the 20.9-km performance run. Muscle biopsies were obtained from the gastrocnemius on days 4 and 7 (both prior to and after the performance run). Trials A, B, and C elevated muscle glycogen to 207, 203, and 159 mmol glucosyl units/kg wet tissue (mmG), respectively. The performance run in both trials A and B utilized significantly more glycogen than in trial C: 5.0 and 5.1 mmG/km vs. 3.1 mmG/km. There were, however, no differences in either performance run times or post-performance run glycogen levels between the trials. These data demonstrate that (1) muscle glycogen can be elevated to high levels with a moderate exercise-diet regimen; (2) initial muscle glycogen levels influence the amount subsequently utilized during exercise; (3) carbohydrate loading is of no benefit to performance for trained runners during a 20.9-km run.
Article
To study the effect of nutrient intake (substrate flux) and training on muscle enzyme activities, 36 untrained healthy men adapted for 7 wk to a fat-rich or a carbohydrate-rich diet. Ten of the 18 subjects on each diet completed an endurance training program, and the remaining 8 served as controls. Maximal oxygen uptake was increased (11%) in the trained groups (P < 0.05). Irrespective of training, beta-hydroxyacyl-CoA-dehydrogenase activity in the vastus lateralis muscle was significantly increased by an average of 25% after adaptation to a fat-rich diet and was unchanged after adaptation to a carbohydrate-rich diet. In contrast, irrespective of diet, muscle citrate synthase activity and hexokinase activity were increased (P < 0.05) after adaptation to training by 17 and 18% in the group fed the carbohydrate, rich diet and by 17 and 12% in the group fed the fat-rich diet, respectively, and were unchanged in the two control groups. We suggest that diet can affect muscle enzymatic adaptation, presumably through an effect on the substrate flux.
Article
Five days of a high-fat diet produce metabolic adaptations that increase the rate of fat oxidation during prolonged exercise. We investigated whether enhanced rates of fat oxidation during submaximal exercise after 5 d of a high-fat diet would persist in the face of increased carbohydrate (CHO) availability before and during exercise. Eight well-trained subjects consumed either a high-CHO (9.3 g x kg(-1) x d(-1) CHO, 1.1 g x kg(-1) x d(-1) fat; HCHO) or an isoenergetic high-fat diet (2.5 g x kg(-1) x d(-1) CHO, 4.3 g x kg(-1) x d(-1) fat; FAT-adapt) for 5 d followed by a high-CHO diet and rest on day 6. On day 7, performance testing (2 h steady-state (SS) cycling at 70% peak O(2) uptake [VO(2peak)] + time trial [TT]) of 7 kJ x kg(-1)) was undertaken after a CHO breakfast (CHO 2 g x kg(-1)) and intake of CHO during cycling (0.8 g x kg(-1) x h(-1)). FAT-adapt reduced respiratory exchange ratio (RER) values before and during cycling at 70% VO(2peak); RER was restored by 1 d CHO and CHO intake during cycling (0.90 +/- 0.01, 0.80 +/- 0.01, 0.91 +/- 0.01, for days 1, 6, and 7, respectively). RER values were higher with HCHO (0.90 +/- 0.01, 0.88 +/- 0.01 (HCHO > FAT-adapt, P < 0.05), 0.95 +/- 0.01 (HCHO > FAT-adapt, P < 0.05)). On day 7, fat oxidation remained elevated (73 +/- 4 g vs 45 +/- 3 g, P < 0.05), whereas CHO oxidation was reduced (354 +/- 11 g vs 419 +/- 13 g, P < 0.05) throughout SS in FAT-adapt versus HCHO. TT performance was similar for both trials (25.53 +/- 0.67 min vs 25.45 +/- 0.96 min, NS). Adaptations to a short-term high-fat diet persisted in the face of high CHO availability before and during exercise, but failed to confer a performance advantage during a TT lasting approximately 25 min undertaken after 2 h of submaximal cycling.
Article
To determine the effect of short-term (3-d) fat adaptation on high-intensity exercise training in seven competitive endurance athletes (maximal O2 uptake 5.0 +/- 0.5 L x min(-1), mean +/-SD). Subjects consumed a standardized diet on d-0 then, in a randomized cross-over design, either 3-d of high-CHO (11 g x kg(-1)d(-1) CHO, 1 g x kg(-1) x d(-1) fat; HICHO) or an isoenergetic high-fat (2.6 g CHO x kg(-1) x d(-1), 4.6 g FAT x kg(-1) x d(-1); HIFAT) diet separated by an 18-d wash out. On the 1st (d-1) and 4th (d-4) day of each treatment, subjects completed a standardized laboratory training session consisting of a 20-min warm-up at 65% of VO2peak (232 +/- 23W) immediately followed by 8 x 5 min work bouts at 86 +/- 2% of VO2peak (323 +/- 32 W) with 60-s recovery. Respiratory exchange ratio (mean for bouts 1, 4, and 8) was similar on d-1 for HIFAT and HICHO (0.91 +/- 0.04 vs 0.92 +/- 0.03) and on d-4 after HICHO (0.92 +/- 0.03) but fell to 0.85 +/- 0.03 (P < 0.05) on d-4 after HIFAT. Accordingly, the rate of fat oxidation increased from 31 +/- 13 on d-1 to 61 +/- 25 micromol x kg(-1) x min(-1) on d-4 after HIFAT (P < 0.05). Blood lactate concentration was similar on d-1 and d-4 of HICHO and on d-1 of HIFAT (3.5 +/- 0.9 and 3.2 +/- 1.0 vs 3.7 +/- 1.2 mM) but declined to 2.4 +/- 0.5 mM on d-4 after HIFAT (P < 0.05). Ratings of perception of effort (legs) were similar on d-1 for HIFAT and HICHO (14.8 +/- 1.5 vs 14.1 +/- 1.4) and on d-4 after HICHO (13.8 +/- 1.8) but increased to 16.0 +/- 1.3 on d-4 after HIFAT (P < 0.05). 1) competitive endurance athletes can perform intense interval training during 3-d exposure to a high-fat diet, 2) such exercise elicited high rates of fat oxidation, but 3) compared with a high-carbohydrate diet, training sessions were associated with increased ratings of perceived exertion.
Article
One limitation shared by all published carbohydrate-loading regimens is that 2-6 d are required for the attainment of supranormal muscle glycogen levels. Because high rates of glycogen resynthesis are reported during recovery from exercise of near-maximal intensity and that these rates could in theory allow muscle to attain supranormal glycogen levels in less than 24 h, the purpose of this study was to examine whether a combination of a short bout of high-intensity exercise with 1 d of a high-carbohydrate intake offers the basis for an improved carbohydrate-loading regimen. Seven endurance-trained athletes cycled for 150 s at 130% VO2peak followed by 30 s of all-out cycling. During the following 24 h, each subject was asked to ingest 12 g.kg-1 of lean body mass (the equivalent of 10.3 g.kg-1 body mass) of high-carbohydrate foods with a high glycemic index. Muscle glycogen increased from preloading levels (+/- SE) of 109.1 +/- 8.2 to 198.2 +/- 13.1 mmol.kg-1 wet weight within only 24 h, these levels being comparable to or higher than those reported by others over a 2- to 6-d regimen. Densitometric analysis of muscle sections stained with periodic acid-Schiff not only corroborated these findings but also indicated that after 24 h of high-carbohydrate intake, glycogen stores reached similar levels in Type I, IIa, and IIb muscle fibers. This study shows that a combination of a short-term bout of high-intensity exercise followed by a high-carbohydrate intake enables athletes to attain supranormal muscle glycogen levels within only 24 h.
Article
High dietary carbohydrate (CHO) intake for several days before competition (CHO loading) is known to increase muscle glycogen stores, with subsequent ergogenic performance benefits often seen in events longer than 90 min in duration. CHO-loading strategies vary in characteristics such as type and duration of dietary manipulation and the accompanying exercise/training activities. Additionally, glycogen concentration may remain elevated for up to 5 d. This versatility in CHO-loading strategies allows the athlete greater flexibility in tailoring pre-event preparation. Women who attempt to CHO load should be particularly attentive to both total energy intake and relative CHO intake; dietary CHO should exceed 8 g x kg body mass(-1) x d(-1) or 10 g x kg lean body mass(-1) x d(-1). As long as the amount ingested is adequate for loading, the type of CHO is less important, with the exception of 1-d loading protocols where the glycemic index may be an important consideration.
Work capacity and dietary intake
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