The Effect of Diet Composition on Performance, Expenditure, Blood Lipids, and Appetite Hormones in Highly Trained Cyclists (DCAP)

• ClinicalTrials.gov Identifier: NCT04097171
• Recruitment Status: Recruiting
• First Posted: September 20, 2019
• Last Update Posted: November 6, 2019
• Sponsor: Texas Christian University
• Information provided by (Responsible Party): Meena Shah, Texas Christian University

Study Description

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.

Condition or disease	Intervention/treatment	Phase
Endurance Cycling Performance	Other: Diet	Not Applicable

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.

Study Design

• Study Type: Interventional (Clinical Trial)
• Estimated Enrollment: 20 participants
• Allocation: Randomized
• Intervention Model: Crossover Assignment
• Masking: None (Open Label)
• Primary Purpose: Basic Science
• 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
• Estimated Study Start Date: November 11, 2019
• Estimated Primary Completion Date: March 30, 2021
• Estimated Study Completion Date: March 30, 2021

Arms and Interventions

Arm	Intervention/treatment
Experimental: High Carbohydrate Diet; Participants will consume a high carbohydrate diet (65-75% of total energy intake). Protein intake will be standardized at 15% of total energy intake.	Other: Diet; Participants will consume each diet for 14 days in a crossover design.
Experimental: Ketogenic Diet; Participants will consume a low carbohydrate diet (<5-10% of total energy intake). Protein intake will be standardized at 15% of total energy intake.	Other: Diet; Participants will consume each diet for 14 days in a crossover design.

Outcome Measures

Primary Outcome Measures :

1. Endurance Cycling Performance [ Time Frame: 180 min after the meal begins ]
   Time to completion in a 30-kilometer simulated time trial

Secondary Outcome Measures :

1. Respiratory Exchange Ratio [ Time Frame: 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 ]
   Indirect calorimetry fasted, postprandial, and during exercise
2. Muscle Fuel Rating [ Time Frame: Change from baseline at 180 min and 240 min after the meal begins ]
   Ultrasound echogenicity of Rectus Femoris
3. Oxygen consumption (VO2) [ Time Frame: At 192 min, 204 min, 216 min, 228 min and 240 min after the meal begins ]
   Indirect calorimetry during exercise
4. Rating of Perceived Exertion (RPE) [ Time Frame: At 192 min, 204 min, 216 min, 228 min and 240 min after the meal begins ]
   6-20 Borg's scale during exercise
5. Thermic Effect of Food (postprandial energy expenditure) [ Time Frame: Change from baseline at 30 min, 60 min, 90 min, 120 min, 150 min, 180 min after the meal begins ]
   Fasted vs. postprandial indirect calorimetry
6. Subjective appetite ratings [ Time Frame: Change from baseline at 60 min, 120 min, 180 min after the meal begins ]
   Visual Analog Scale (Scale 1: Perception of Hunger [0-100 mm]; Scale 2: Perception of Fullness [0-100 mm]; Scale 3: Desire to Eat [0-100 mm]
7. Appetite hormones including ghrelin, leptin, insulin, and Peptide-YY [ Time Frame: Change from baseline at 30 min, 60 min, 120 min, 180 min and 240 min ]
   Fasted, postprandial & post exercise blood concentration of appetite hormones
8. Blood glucose [ Time Frame: Change from baseline at 180 min and 240 min after the meal begins; on day 7 of each diet ]
   Fasted, postprandial & post exercise blood concentration of glucose
9. Blood pressure [ Time Frame: Change from baseline at 180 min after the meal begins ]
   Fasted, postprandial & post exercise
10. Cognitive function [ Time Frame: At 180 min and 240 min after the meal begins ]
    Stroop test
11. Mood state questionnaire [ Time Frame: At 180 min and 240 min after the meal begins ]
    Abbreviated Profile of Mood States; 40-item scale; Likert scale from 0 = "not at all" to 4 = "extremely"
12. Resting Metabolic Rate [ Time Frame: At baseline before meal begins ]
    Indirect calorimetry in fasted state
13. Blood lipids including (triglycerides, total cholesterol, low density lipoprotein, and high-density lipoprotein) [ Time Frame: 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 ]
    Fasted and postprandial in mg/dL

Eligibility Criteria

• Ages Eligible for Study: 18 Years to 65 Years (Adult, Older Adult)
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

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

Contacts and Locations

Contacts

Contact: Meena Shah, PhD; 817-257-6871; m.shah@tcu.edu

Contact: Andreas Kreutzer; 817-257-6859; a.kreutzer@tcu.edu

Locations

United States, Texas

Texas Christian University; Recruiting

Fort Worth, Texas, United States, 76129

Contact: Meena Shah, Ph.D. m.shah@tcu.edu

Principal Investigator: Meena Shah, Ph.D.

Sponsors and Collaborators

Texas Christian University

More Information

• Responsible Party: Meena Shah, Interim Chair, Professor and Director, Graduate Program, Texas Christian University
• ClinicalTrials.gov Identifier: NCT04097171 History of Changes
• Other Study ID Numbers: CT2019MS3
• First Posted: September 20, 2019
• Last Update Posted: November 6, 2019
• Last Verified: November 2019

Individual Participant Data (IPD) Sharing Statement:

• Plan to Share IPD: Yes
• Plan Description: De-identified study data of all outcome variables will be shared on an Open Science Framework project page (osf.io) along with the study protocol, statistical analysis plan, and analytic code
• Supporting Materials: Study Protocol; Statistical Analysis Plan (SAP); Analytic Code
• Time Frame: Will become available at the latest June 2021 and be available indefinitely
• Access Criteria: Openly available
• URL: http://osf.io/ujx6e/

• Studies a U.S. FDA-regulated Drug Product: No
• Studies a U.S. FDA-regulated Device Product: No