Clinical trial NCT04097171: The Effect of Diet Composition on Performance, Expenditure, Blood Lipids, and Appetite Hormones in Highly Trained Cyclists
Official title: The Effect of Diet Composition on Performance, Energy Expenditure, Blood Lipids and Lipoproteins, and Cognitive Function and Mood States in Highly Trained Cyclists
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Endurance Cycling Performance
Lead sponsor: Texas Christian University
Sponsor class: OTHER
First posted: 2019-09-20
Enrollment: 34
Sex: ALL
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: BASIC_SCIENCE

Brief summary: This study employs a crossover design to evaluate the effect of two different diets (high carbohydrate vs. ketogenic) and corresponding test meals on endurance exercise performance, energy expenditure including resting metabolic rate and thermic effect of food, postprandial responses of blood lipids, glucose and appetite hormones, and cognitive function and mood states.

Detailed description: Traditionally, a high carbohydrate diet is recommended for elite endurance athletes and sub-elite, highly trained recreational athletes competing in endurance events. However, recently the ketogenic diet (extremely low carbohydrate content) has become popular in these populations. The effect on endurance exercise performance, energy expenditure, postprandial blood profiles, and cognitive function and mood states requires further investigation.

In this study, highly trained recreational cyclists and triathletes will adhere to each diet (high-carbohydrate and ketogenic) for 14 days in a crossover design. Experimental trials at baseline and after each diet will evaluate endurance cycling performance (time trial), resting energy expenditure, the thermic effect of food of test meals corresponding in composition to each diet, postprandial responses of blood lipids, glucose and appetite hormones, and cognitive function and mood states.

Eligibility criteria: Inclusion Criteria:

* \>100-150km of cycling per week
* VO2max \> 80th percentile for sex and age (adjusted for cycle ergometry)
* apparently healthy

Exclusion Criteria:

* weight loss supplements/medications/diet
* extreme dietary patterns (e.g. extremely high or low carbohydrate)
* nicotine use
* heavy alcohol use (\>7 drinks/week female; \>14 drinks/week male)
* food allergies
* diabetes
* heart disease
* stroke
* liver/kidney/thyroid disease
* anemia
* eating disorders
* uncontrolled hypertension
* pulmonary/orthopedic/musculoskeletal problems that prevent exercise
* surgery that affects swallowing and digestion
* claustrophobia

Primary outcomes:
measure: Endurance Cycling Performance
timeFrame: 180 min after the meal begins
Secondary outcomes:
measure: Respiratory Exchange Ratio
timeFrame: Change from baseline at 30 min, 60 min, 90 min, 120 min, 150 min, 180 min, 192 min, 204 min, 216 min, 228 min and 240 min after the meal begins
measure: Muscle Fuel Rating
timeFrame: Change from baseline at 180 min and 240 min after the meal begins
measure: Oxygen consumption (VO2)
timeFrame: At 192 min, 204 min, 216 min, 228 min and 240 min after the meal begins
measure: Rating of Perceived Exertion (RPE)
timeFrame: At 192 min, 204 min, 216 min, 228 min and 240 min after the meal begins
measure: Thermic Effect of Food (postprandial energy expenditure)
timeFrame: Change from baseline at 30 min, 60 min, 90 min, 120 min, 150 min, 180 min after the meal begins
measure: Subjective appetite ratings
timeFrame: Change from baseline at 60 min, 120 min, 180 min after the meal begins
measure: Appetite hormones including ghrelin, leptin, insulin, and Peptide-YY
timeFrame: Change from baseline at 30 min, 60 min, 120 min, 180 min and 240 min
measure: Blood glucose
timeFrame: Change from baseline at 180 min and 240 min after the meal begins; on day 7 of each diet
measure: Blood pressure
timeFrame: Change from baseline at 180 min after the meal begins
measure: Cognitive function
timeFrame: At 180 min and 240 min after the meal begins
measure: Mood state questionnaire
timeFrame: At 180 min and 240 min after the meal begins
measure: Resting Metabolic Rate
timeFrame: At baseline before meal begins
measure: Blood lipids including (triglycerides, total cholesterol, low density lipoprotein, and high-density lipoprotein)
timeFrame: Change from baseline at 30 min, 60 min, 120 min, 180 min, 192 min, 204 min, 216 min, 228 min and 240 min after the meal begins
Other outcomes:
Locations:
city: Fort Worth
country: United States
facility: Texas Christian University
state: Texas
Study officials:
References: