Anomalies Gastrointestinal
Conditions
Brief summary
Several previous studies have shown that repeatedly ingesting carbohydrate supplements during exercise training sessions, over a period of days and weeks, can gradually increase carbohydrate oxidation and reduce gut discomfort during exercise. However, repeatedly ingesting large amounts of carbohydrate during training sessions can be burdensome and can cause gut distress. Thus, it would be advantageous if the same long-term benefits could be realized from consuming these carbohydrate supplements at rest instead of specifically during training sessions. Therefore, the goal of this study is to examine whether repeatedly ingesting a carbohydrate-rich beverage at rest over a 5-day period alters metabolism and gut symptoms while ingesting carbohydrate during exercise.
Interventions
DIETARY_SUPPLEMENTCarbohydrate Beverage
The carbohydrate beverage will supply approximately 100 grams of carbohydrate per day (in the form of glucose and fructose)
DIETARY_SUPPLEMENTPlacebo Beverage
The placebo beverage will contain aspartame.
Sponsors
Old Dominion University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Be currently running ≥15 miles per week * Have completed at least one run \>60 minutes over the past month * Have completed one or more marathons within the past year
Exclusion criteria
* Overt cardiovascular disease or metabolic disorder * Adverse symptoms (e.g., unusual shortness of breath, dizziness, chest pain) with exercise * Allergies/intolerances to any of the ingredients in the beverages
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Gastrointestinal Symptom Ratings | Symptoms will be collected during a 60 minute run on a treadmill at a baseline visit and at a second visit after ingesting the carbohydrate or placebo beverage for 5 days. | Symptoms such as nausea, fullness, belching, reflux, abdominal cramps, flatulence, and urge to defecate will be recorded on a 0-10 scale (0 = no discomfort, 10 = unbearable discomfort). |
| Change in Hydrogen Breath Production | Samples will be collected before after a 60-minute run at a baseline visit and at a second visit after ingesting the carbohydrate or placebo beverage for 5 days. | Samples of expired air will be tested for hydrogen levels, a marker of carbohydrate malabsorption |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Carbohydrate Oxidation | Respiratory gases will be collected during each 60-minute run at a baseline visit and at a second visit after ingesting the carbohydrate or placebo beverage for 5 days. | Respiratory gases will be used to estimate carbohydrate oxidation rates. |
| Change in Feeling Scale | Ratings will be collected collected before and during each 60-minute run at a baseline visit and at a second visit after ingesting the carbohydrate or placebo beverage for 5 days. | A bipolar scale ranging from -5 (very bad) to +5 (very good) |
Countries
United States
Outcome results
None listed