Dietary Supplementations
Conditions
Keywords
glycogen, glucose, aerobic exercise, time to exhaustion, supplementation, protein, endurance, recovery
Brief summary
The purpose of this study is to determine whether the consumption of a carbohydrate, carbohydrate plus protein, or placebo sports drink during a 2-hour recovery period effectively moderates performance decrements during a subsequent bout of high-intensity exercise. This information will benefit any endurance-trained masters class athlete who may need to compete or train multiple times a day.
Detailed description
To test the hypothesis, this study will utilize a randomized, double-blind, placebo-controlled between-subject design to examine the effects of carbohydrate (CHO) and carbohydrate-protein (CHO-P) supplementation on short-term recovery following aerobic interval exercise (INT) and time to exhaustion (TTE) testing in maters class athletes. After completing the informed consent and screening process (Visit #1), each participant will be assessed for their anthropometric measures as well as body composition and will complete a graded exercise test to volitional exhaustion on a cycle ergometer to determine VO2peak. Forty-eight to 72 hours after Visit #1, or VO2peak testing, participants will return to the lab for familiarization with the INT exercise protocol and TTE test (Visit #2). Within forty-eight to 72 hours after familiarization (Visit #2), participants will return to the lab for Visit #3 to complete INT exercise and TTE, a 2-hour passive recovery period including the consumption of one of three treatments (CHO, CHO-P, PLA), followed by repeated INT exercise and TTE, heart rate variability and sweat rate determination. Participants will also complete the Nutritional Recovery Practices, Knowledge, and Beliefs of Australian Triathletes survey during the 2-hour recovery period. Participants will be asked to complete the ASA24®, an automated self-administered 24-hour dietary assessment tool during the 5-9-day period between familiarization (Visit #2) and the experimental protocol (Visit #3).
Interventions
DIETARY_SUPPLEMENTCarbohydrate
Participants have a one in three chance of consuming a carbohydrate beverage between two bouts of high-intensity exercise.
DIETARY_SUPPLEMENTCarbohydrate-Protein
Participants have a one in three chance of consuming a carbohydrate-protein beverage between two bouts of high-intensity exercise.
DIETARY_SUPPLEMENTPlacebo
Participants have a one in three chance of consuming a placebo beverage between two bouts of high-intensity exercise.
Sponsors
Erica Goldstein
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
DOUBLE (Subject, Outcomes Assessor)
Masking description
The primary investigator will not be blinded to the treatment groups. However, both the research assistants responsible for administering the experimental protocol (aerobic interval and time to exhaustion testing) and the participants will be.
Intervention model description
Participants will be randomized to one of three groups: isocaloric carbohydrate (1.2 g/kg of body weight), carbohydrate-protein (0.8 g/kg body weight carbohydrate + 0.4 g/kg body weight protein), or placebo (flavored water). All three beverages will have a similar appearance and taste and participants will be blinded to the contents. All beverages will contain the same volume of fluid (1 liter).
Eligibility
Sex/Gender
MALE
Age
35 Years to 59 Years
Healthy volunteers
Yes
Inclusion criteria
* Men between the ages of 35 and 59 years * Free of any physical limitations as determined by the Exercise Preparticipation Health Screening Questionnaire for Exercise Professionals (PHSQEP), and a Physical Activity Readiness Questionnaire for Everyone (PAR-Q+) * Regularly engaged in endurance exercise (running, cycling, swimming) for a minimum of three years, a weekly training volume of 5-10 hours, and a maximal oxygen uptake of 45.00 ml·kg-1·min-1 or higher as determined by completion of VO2peak assessment (Visit #1).
Exclusion criteria
* Recent musculoskeletal injuries or surgeries * Any chronic illness that requires continuous medical care * Current incarceration, cognitive impairment or inability to provide consent * Present or past use of performance-enhancing drugs
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Time to Exhaustion (TTE) | Visit #3 (Day 7) | Participants cycle for as long as possible at 90% of peak power output (watts) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Heart Rate Variability (HRV) | Visit #3 (Day 7) | R-R intervals recorded via a heart rate monitor and Elite HRV will be downloaded and analyzed using a laptop with commercially available HRV analysis software. Root mean square of the successive differences of R-R intervals (RMSSD) values will be recorded during the 90% TTE and then post-exercise every 5 min (end of TTE, 5min, 10min, 15min, 20min, 25min, 30min). |
| Sweat Rate (SR) | Visit #3 (Day 7) | Sweat rate will be determined based on the difference between pre-and post-weight changes for each bout of exercise, the amount of fluid consumed during the recovery period, and total exercise time in minutes. |
Countries
United States
Outcome results
None listed