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Food and Fluid Guidelines Before, During, and After Exercise

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Abstract

Athletes who are properly fueled and hydrated before, during, and after exercise can improve training, increase performance, and decrease fatigue. Many commercial products are marketed to athletes and are designed to be consumed at specific periods: before, during, and after exercise. Are these products really necessary? This article reviews the research on nutrition support for the athlete surrounding exercise and discusses the different nutritional needs of the recreational athlete versus the elite athlete. Guidelines for macronutrient intake before, during, and after exercise are provided along with decision trees to help the practitioner guide the athlete to proper fueling strategies.

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... To this end, it is recommended to consume 500 ml of fluid 2 h before the event followed by 125-250 ml 15-30 min before the event. [20,21] For endurance events such as a football (soccer) match, the aim of nutrition strategy during exercise is to conserve muscle glycogen and to maintain blood glucose and electrolytes levels. ...
... A carbohydrate-rich meal should be consumed approximately 2 h following the postevent food intake later. [20,21] With respect to fluid intake, at least 500 ml should be consumed during the first 2 h after the competition, and fluid intake should be continued at regular intervals to replace fluid losses. ...
... The ratio of the group allocation is 1:1:1, therefore, 15 participants were allocated for each group. Inclusion criteria were individuals aged between 18 to 25 years old, who have hamstring tightness, and undertake sports at least once a week for leisure (Rosenbloom 2012). Hamstring tightness was defined as receiving a score less than 30cm in males and 33cm in females in sit-and-reach test (Ayala et al. 2012). ...
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Background and Objective: Hamstring strain is one of the most common sports injuries contributed by lack of hamstring flexibility as one of the injury risks factors. Eccentric training could serve to reduce the risk of hamstring strain by improving hamstring flexibility. However, the effectiveness of different eccentric hamstring exercise in improving hamstring flexibility is still understudied. The aim of this study is to compare the effectiveness of eccentric exercises and static stretching exercise on hamstring flexibility of recreational athletes. Methods: A randomized controlled trial was carried out to examine the effects of Nordic Hamstring Exercise (NHE) and Sliding Leg Curls (SLC) on hamstring flexibility of recreational athlete for four weeks. Participants with hamstring tightness were classified as sit and reach test score for less than 30cm for males and 33cm for females. Participants were randomly assigned using sequentially numbered, opaque, and sealed envelopes to three equal groups (n = 15 for each group): NHE, SLC and Static Stretching (SS). Assessor was blinded from participants' group assignment. Results: A total of 45 recreational athletes (28 male and 17 female), mean age 20.36 ± 1.25 years participated in the study. There was no difference between eccentric hamstring (NHE and SLC) and static stretching exercise in improving hamstring flexibility (p = 0.82). NHE and SLC exercises are equally effective in increasing hamstring flexibility [NHE: p < 0.0001, ES = 0.90, 95% CI (4.36, 6.77); SLC: p < 0.0001, ES = 0.70, 95% CI (4.26, 6.09)], as to static stretching [SS: p < 0.0001, ES = 0.62, 95% CI (3.18, 4.71)]. Conclusion: Eccentric hamstring exercises are equally effective as static stretching in improving hamstring muscle flexibility.
... Devising robust pre-fight meal prescriptions is currently difficult (Slater and Phillips 2011), however benefits in repeated high intensity efforts have been shown with carbohydrate intakes ≥1g/kg BM in the hours before exercise (Lambert, Flynn et al. 1991). Although athletes' preferences and the likelihood of GI distress must be considered, the consumption of easily digested, low-fat, low-fibre and low gas producing carbohydrate-rich choices before and between bouts seems a reasonable target (Rosenbloom 2012). Of course, some fighters concerned with gastrointestinal distress (potentially exacerbated by gut contact during competition) feel unable to consume foods or fluids in the hours pre-event. ...
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Olympic combat sports separate athletes into weight divisions, in an attempt to reduce size, strength, range and/or leverage disparities between competitors. Official weigh-ins are conducted anywhere from 3 and up to 24 h prior to competition ensuring athletes meet weight requirements (i.e. have ‘made weight’). Fighters commonly aim to compete in weight divisions lower than their day-to-day weight, achieved via chronic and acute manipulations of body mass (BM). Although these manipulations may impair health and absolute performance, their strategic use can improve competitive success. Key considerations are the acute manipulations around weigh-in, which differ in importance, magnitude and methods depending on the requirements of the individual combat sport and the weigh-in regulations. In particular, the time available for recovery following weigh-in/before competition will determine what degree of acute BM loss can be implemented and reversed. Increased exercise and restricted food and fluid intake are undertaken to decrease body water and gut contents reducing BM. When taken to the extreme, severe weight-making practices can be hazardous, and efforts have been made to reduce their prevalence. Indeed some have called for the abolition of these practices altogether. In lieu of adequate strategies to achieve this, and the pragmatic recognition of the likely continuation of these practices as long as regulations allow, this review summarises guidelines for athletes and coaches for manipulating BM and optimising post weigh-in recovery, to achieve better health and performance outcomes across the different Olympic combat sports.
... Male recreational athletes ranging from 18 to 25 years old were recruited. In this study, recreational athletes were defined as people who undertake sports for leisure [15] and do not represent any college, national, or international teams [16]. Participants with histories of developing pain in the lower limbs because of motor vehicle accidents, sports injuries, and assaults to the lower limb, those who have been diagnosed with musculoskeletal, vestibular, and neurological disorder, and those on medication were excluded. ...
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This study aimed to determine the effects of Kinesio® taping (KT) on dynamic postural control following fatigue induction. It is hypothesized that the application of KT limits the effects of fatigue on dynamic postural control. This study used a randomized controlled trial recruited 32 male recreational athletes, randomized to one of the two groups (Group A: KT and fatigue and Group B: KT and no fatigue). Fatigue was induced using the adapted Functional Agility Short Term Fatigue Protocol (FAST-FP). The rectus femoris of quadriceps, biceps femoris of the hamstring and medial gastrocnemius of the dominant leg were taped. The dynamic postural control was assessed pre and post fatigue. A significant interaction was observed between the group and time for the anterior-posterior position (p=0.03, ηp2=0.21) while non-significant interaction was observed in the lateral symmetry (p=0.84, ηp2=0.001). A significant main effect of time was observed for anterior-posterior position (p>0.05, ηp2=0.15) while non-significant for the lateral symmetry (p=0.65, ηp2=0.007). For the main effect of the two groups was not significant for the anterior-posterior position (p=0.42, ηp2=0.02) and lateral symmetry (p=0.73, ηp2=0.004). In conclusion, the diminishing effect of fatigue on the anterior-posterior position was observed. Moreover, KT application does not limit the effects of fatigue on the dynamic postural control.
... Although carbohydrate consumption is not essential for training sessions with a duration of less than 60 minutes (such as the ones that took place during Winter), carbohydrate was important for the longer training sessions (70 minutes) in Autumn to maintain blood glucose levels and sustain athletic performance [38,43,44]. Although in theory the intake of carbohydrate is not as important for exercise of short duration players from a low socio-economic environment, such as these where 28% of players were classified as wasted may well need to consume carbohydrate during training. ...
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Background: Poor hydration compromises performance and heightens the risk of heat stress which adolescents are particularly susceptible to as they produce comparatively larger amount of metabolic heat during exercise. This study determined the hydration status and fluid intake of socio-economically disadvantaged, male adolescent soccer players during training. Methods: A pilot study was conducted among 79 soccer players (mean age 15.9 ± 0.8 years; mean BMI 20.2 ± 2.1 kg/m(2)). Hydration status was determined before and after two training sessions, using both urine specific gravity and percent loss of body weight. The type and amount of fluid consumed was assessed during training. A self-administered questionnaire was used to determine the players' knowledge regarding fluid and carbohydrate requirements for soccer training. Results: Players were at risk of developing heat illness during six of the 14 training sessions (60 - 90 minutes in length). Although on average players were slightly dehydrated (1.023 ± 0.006 g/ml) before and after (1.024 ± 0.007 g/ml) training, some were extremely dehydrated before (24%) and after (27%) training. Conversely some were extremely hyperhydrated before (3%) and after training (6%). The mean percent loss of body weight was 0.7 ± 0.7%. The majority did not consume fluid during the first (57.0%) and second (70.9%) training sessions. An average of 216.0 ± 140.0 ml of fluid was consumed during both training sessions. The majority (41.8%) consumed water, while a few (5.1%) consumed pure fruit juice. More than 90% stated that water was the most appropriate fluid to consume before, during and after training. Very few (5.0%) correctly stated that carbohydrate should be consumed before, during and after training. Conclusions: Approximately a quarter were severely dehydrated. Many did not drink or drank insufficient amounts. The players' beliefs regarding the importance of fluid and carbohydrate consumption did not correspond with their practices. A nutrition education programme is needed to educate players on the importance of fluid and carbohydrate to prevent dehydration and ensure appropriate carbohydrate intake.
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Objectives. The present study examined beliefs surrounding food culture in youth athletics. Design. Qualitative research. Methods. Coaches (n = 62), parents (n = 161), and youth athletes (n = 40) in the USA completed questionnaires that explored aspects of the food environment of youth athletics, including practices related to food and beverage consumption and perspectives on the nutritional value of available foods and beverages. Results. Coaches, parents, and athletes all reported a high number of available foods and beverages, and were mixed both about whether these were healthy or unhealthy, and whether the availability of unhealthy foods and beverages was problematic. Conclusions. This study aimed to add to the literature an examination of multiple perspectives on the current food culture in youth athletics. Participant perspectives suggest that the food environment of youth sport may be an unhealthy mismatch with the physical, social, and psychological benefits of participation. Further research could aim to identify optimal environments for promoting health in youth sport. Limitations and additional directions for future research are discussed.
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