None listed
Conditions
Brief summary
The health benefits of proper hydration have long been recognized. A major component of the hydration process involves thirst which, depending on drinking availability, leads to voluntary fluid intake. Exercising to fatigue (which commonly occurs in adolescent athletes) creates conditions that are similar to acute dehydration. Acutely, fluid restoration is effective in restoring fluid balance in these situations and improving exercise performance. Adolescent athletes are particularly prone to the effects of acute dehydration during exercise. They frequently remain unaware or simply ignore thirst during exercise which may result in significant dehydration leading to poor exercise performance. The physiological effects of dehydration are well documented in athletes. In particular acute dehydration with exercise results in impaired of cardiac performance and inefficient oxygen delivery to the tissues, being a critical factor in severely limiting peak exercise performance very early on in exercise. The most important issue to remember here is that this impairment in exercise performance is preventable with an appropriate hydration strategy. Strategies utilizing oral fluid loading using sports drinks immediately prior to exercise have the potential to reduce the negative effects that early dehydration may have on cardiac performance. Current research supports a continued increase in Stroke Volume (SV) during exercise. This increase may well be augmented in adolescent athletes by a hydration strategy that preloads with oral fluid immediately prior to exercise. This is the underlying hypothesis of the study. If the hypothesis is proven to be correct, that preloading with oral fluid improves cardiac performance in adolescent athletes then the same can be said of older children during exercise. We would then have a scientifically proven hydration strategy for use in older children to prevent early dehydration with exercise and produce maximum exercise performance. This is a blinded randomise controlled trial involving 350 childhood athletes attending sports high schools in the Sydney West region. Participants are initially randomised to two groups. All participants are evaluated at baseline for hydration status, aerobic exercise and cardiac performance. The participants are then reevaluated 1 week later with hydration status controlled 24 hours prior to retesting. One group will be the intervention group (being preloaded immediately prior to exercise with oral fluid equivalent to half normal saline) and will receive GatoradeR 20mL/kg 15 minutes prior to exercise. All participants are then retested to determine differences in hydration status, aerobic exercise performance and cardiac performance between groups.
Interventions
Oral fluid loading using sport drinks (Gatorade R) immediately prior to exercise. Gatorade is a about half normal saline with 8% dextrose. On average for each 100 mL it contains Carbohydrate 6.3g;], Sodium 47mg, and Potassium 22.5mg.
A single session baseline exercise assessment will be conducted 1 week before the intervention. Each subject will be perform a running exercise in the upright position on a treadmill (TrackmasterR TMX425 treadmill) with a complete penal of metabolic parameters co
Oral fluid loading using sport drinks (Gatorade R) immediately prior to exercise. Gatorade is a about half normal saline with 8% dextrose. On average for each 100 mL it contains Carbohydrate 6.3g;], Sodium 47mg, and Potassium 22.5mg. A single session baseline exercise assessment will be conducted 1 week before the intervention. Each subject will be perform a running exercise in the upright position on a treadmill (TrackmasterR TMX425 treadmill) with a complete penal of metabolic parameters collected using the MedgraphicsR CPX/D breath by breath gas exchange system. Subjects will be evaluated according to the Bruce protocol to the point of exhaustion usually 25-30 minutes after the warm-up period. At the retesting session, subjects in the treatment group will receive Gatorade 20mL/Kg 15 minutes prior to the exercise assessment. The same routine of exercise will be performed by each subject and in the same manner as the baseline session.
Sponsors
Gary J Browne
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Prevention
Masking
Blinded (masking used)
Eligibility
Sex/Gender
All
Age
12 Years to 16 Years
Healthy volunteers
No
Inclusion criteria
High school adolescents, both males and females, aged between 12 and 16 years who are physically fit and are free of known illnesses or diseases that may affect their exercise ability. Due to the fact that the study is specifically aiming to develop hydration strategies for elite and even professional sports players and young people who usually involve in high intensity exercise, ordinary adolescents are not considered as the target population. Potential subjects will be recruited only from regional high schools that are designated as centres of excellence for Sports, hence, the inclusion criteria are the high school students aged between 12 and 16 years who are attending one of the regional Sports High School within the catchment areas of he Sydney West Area Health Services.
Exclusion criteria
Students who are diagnosed with any chronic illnesses and diseases that may affect their exercise ability and students who are diagnosed as over weight and obese will not be included in the study.
Outcome results
None listed