Rehydration Following Exercise-Induced Dehydration

Dehydration Related to Exercise Clinical Trial

Official title:

Rehydration Following Exercise-Induced Dehydration: Beverage Formula Effects in Team Sport Athletes

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01974986
• Other study ID #: AN-US-1307
• Status: Completed
• Phase: N/A
• First received: October 28, 2013
• Last updated: May 31, 2016
• Start date: July 2013
• Est. completion date: May 2016

Study information

• Verified date: May 2016
• Source: University of Illinois at Chicago
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Interventional

Clinical Trial Summary

Athletes participating in multiple training sessions a day can be at increased risk of suboptimal hydration and heat illness during their second training session, especially when the environment is hot and humid. With the exception of the absolute volume of water delivered by a rehydration beverage, characteristics of the beverage consumed play a role in the recovery and completeness of rehydration. The amount of sodium in the beverage has been shown to be a primary factor in rehydration. Recently, an effect of the carbohydrate concentration of the beverage was been reported, with its effects mediated by the renal system in response to elevated serum insulin. The purpose of this study is to compare sodium and carbohydrate effects on rehydration and recovery.

Description:

The effectiveness of beverage composition will be evaluated by modifying the sodium content and carbohydrate content of the beverage. Hypothesis: Completeness of rehydration will be greater in the beverage with higher sodium concentration. It is also hypothesized that electrolyte-carbohydrate beverages will promote rehydration that exceeds that of consuming placebo (water). Using a randomized balanced-treatment crossover design, physically trained males (18-35 yrs) will participate in intermittent exercise for 85 to 100 minutes in three experimental trials of variable intensity training in the heat (30 +/-3 C) followed by a rehydration-recovery period. Exercise will be done at varying intensities (intermittent intervals) ranging from 50% to nearly 100% of maximum oxygen uptake (max VO2) determined prior to the experimental trials. During the 85 to 100 min of exercise, no fluids will be given during the trial to elicit an acute reduction in body mass of approximately 2.5 to 3% (standardized for each subject). Following exercise, 100% of the volume of fluid lost will be replaced with one of the beverages. Beverages will be ingested in six aliquots over a 1-hr period given at the end of the trial. Retention of fluid will be calculated by measuring volume of urine lost at 30, 60, 135, and 210 min following ingestion of the rehydration beverage. The primary outcome variable is the percentage of fluid retained, i.e., the difference between volume ingested and cumulative urine produced in 3.5 h as a percentage of volume ingested. Body mass, urine specific gravity, total body water, and ratings of vigor and affect will be assessed prior to exercise, after exercise in a state of dehydration, and at 210 min post-exercise following rehydration. A one-way ANOVA will be used to test the hypothesis for rehydration, the primary outcome variable.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 26
• Est. completion date: May 2016
• Est. primary completion date: May 2015
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Male
• Age group: 18 Years to 35 Years

Eligibility

Inclusion Criteria:

• Male, age 18-35 y, physically fit, and regularly undergoing exercise training particularly but not exclusively in team sports.

Exclusion Criteria:

• "Yes" on PAR-Q survey, symptoms or signs of exercise intolerance, VO2 max <50 mL/kg/min, smoker

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Crossover Assignment, Masking: Double Blind (Subject, Investigator, Outcomes Assessor), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Dehydration
• Dehydration Related to Exercise

Intervention

Other:
• Water with flavoring and non-nutritive sweetener.
A volume of fluid (water) was given after exercise to return each subject's body mass (to euhydration).
• High-Na low-CHO beverage
A volume of fluid (high-Na, low-CHO) was given after exercise to return each subject's body mass (to euhydration).
• Low-Na high-CHO beverage
A volume of fluid (low-Na, high-CHO) was given after exercise to return each subject's body mass (to euhydration).

Locations

Country	Name	City	State
United States	University of Illinois	Chicago	Illinois

Sponsors (2)

Lead Sponsor	Collaborator
University of Illinois at Chicago	Abbott Nutrition

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Total body water	Change in estimated total body water from the start of data collection.	8 hours	No
Primary	Rehydration	Fluid retained to rehydrate the body as a percentage of volume of beverage ingested.	8 hours	No
Secondary	Body weight	Change in body mass from the start of data collection.	8 hours	No