Exercise Substrate Utilisation and Endurance Performance Following Short-term Manipulation of Dietary Fat Intake

• ClinicalTrials.gov Identifier: NCT02568592
• Recruitment Status: Unknown
• First Posted: October 6, 2015
• Last Update Posted: May 13, 2016
• Sponsor: University of Birmingham
• Collaborator: GlaxoSmithKline
• Information provided by (Responsible Party): University of Birmingham

Tracking Information

• First Submitted Date: May 13, 2015
• First Posted Date: October 6, 2015
• Last Update Posted Date: May 13, 2016
• Study Start Date: March 2015
• Estimated Primary Completion Date: June 2016 (Final data collection date for primary outcome measure)

Current Primary Outcome Measures (submitted: October 2, 2015)

Rates of fat oxidation during exercise [ Time Frame: 90 minutes of sub-maximal exercise ]

Rates of fat oxidation to be measured via indirect calorimetry during 90 minutes of submaximal exercise

• Original Primary Outcome Measures: Same as current

Current Secondary Outcome Measures (submitted: October 2, 2015)

• 5km running performance [ Time Frame: Immediately following measurement of Primary Outcome measure ]
  Time to complete 5km on a treadmill
• Change in plasma glucose concentration [ Time Frame: 90 minutes sub-maximal exercise ]
  Area under the plasma concentration versus time curve (AUC) of glucose
• Change in Free Fatty Acid concentration [ Time Frame: 90 minutes sub-maximal exercise ]
  Area under the plasma concentration versus time curve (AUC) of Free Fatty Acid
• Change in plasma glycerol concentration [ Time Frame: 90 minutes sub-maximal exercise ]
  Area under the plasma concentration versus time curve (AUC) of glycerol

• Original Secondary Outcome Measures: Same as current
• Current Other Pre-specified Outcome Measures: Not Provided
• Original Other Pre-specified Outcome Measures: Not Provided

Descriptive Information

• Brief Title: Exercise Substrate Utilisation and Endurance Performance Following Short-term Manipulation of Dietary Fat Intake
• Official Title: Exercise Substrate Utilisation and Endurance Performance Following Short-term Manipulation of Dietary Fat Intake in Women

Brief Summary

The capacity to burn fat as fuel for exercise may have important implications for sporting performance, with dietary fat intake positively influencing this ability.

Endurance performance and the ability to burn fat will be measured in women runners following the consumption of 3 diets varying in the amount of fat and carbohydrate.

• Detailed Description: Dietary fat intake positively influences the ability to burn fat during exercise in women but not men, whereas carbohydrate intake negatively influences fat oxidation in both sexes. The independent nature of dietary fat intake as a predictor of the ability to burn fat in women suggests that in conditions of adequate carbohydrate intake providing additional fat may increase fat oxidation in women whereas it does not in men. It is of interest to explore if indeed women are responsive (i.e., increase in fat oxidation) to short-term increases in dietary fat intake induced by overfeeding (adequate carbohydrate) or if as appears to be the case in men reduced carbohydrate intake as typically employed in high-fat, low carbohydrate dietary studies is also a prerequisite for enhancing fat oxidation in women, and whether this translates into a difference in exercise endurance performance.
• Study Type: Interventional
• Study Phase: Not Applicable
• Study Design: Allocation: Randomized; Intervention Model: Crossover Assignment; Masking: None (Open Label); Primary Purpose: Basic Science
• Condition: Dietary Modification

Intervention

• Dietary Supplement: High Fat
  High Fat - Carbohydrate (20%), Fat (65%), Protein (15%)
• Dietary Supplement: Normal
  Normal - Carbohydrate (50%), Fat (35%) and Protein (15%)
• Dietary Supplement: Normal + Extra Fat
  Normal + Extra Fat - Carbohydrate (50%), Fat (65%), Protein (15%). Carbohydrate and protein intake identical in absolute amounts to NORMAL, with an additional 30% extra energy coming from fat.

Study Arms

• Experimental: High Fat
  High Fat - Carbohydrate (20%), Fat (65%), Protein (15%)
  Intervention: Dietary Supplement: High Fat
• Experimental: Normal
  Normal - Carbohydrate (50%), Fat (35%) and Protein (15%)
  Intervention: Dietary Supplement: Normal
• Experimental: Normal + Extra Fat
  Normal + Extra Fat - Carbohydrate (50%), Fat (65%), Protein (15%). Carbohydrate and protein intake identical in absolute amounts to NORM (Normal), with an additional 30% extra energy coming from fat.
  Intervention: Dietary Supplement: Normal + Extra Fat

• Publications *: Not Provided

Recruitment Information

• Recruitment Status: Unknown status
• Actual Enrollment (submitted: October 2, 2015): 16
• Original Estimated Enrollment: Same as current
• Estimated Study Completion Date: June 2016
• Estimated Primary Completion Date: June 2016 (Final data collection date for primary outcome measure)

Eligibility Criteria

Inclusion Criteria:

• BMI >17.0 < 25 kg/m2
• Good General Health
• Accustomed to vigorous physical activity
• Run > 2 times per week
• V̇O2max >50ml/kg/min
• Weight Stable > last 6months
• Non Smoker
• Pre-menopausal, and either eumenorrheic and regularly menstruating, or using monophasic hormonal oral contraceptives for > 3 months.

Exclusion Criteria:

• Currently taking part in another scientific/clinical study
• Taking any prescription drug / supplement thought to influence metabolism
• Following unusual dietary practices (such as intermittent fasting or low carbohydrate diets)
• Pregnant
• Breast Feeding

Sex/Gender

• Sexes Eligible for Study: Female

• Ages: 18 Years to 45 Years (Adult)
• Accepts Healthy Volunteers: Yes
• Contacts: Contact information is only displayed when the study is recruiting subjects
• Listed Location Countries: United Kingdom

Administrative Information

• NCT Number: NCT02568592
• Other Study ID Numbers: ERN_15-0012
• Has Data Monitoring Committee: No
• U.S. FDA-regulated Product: Not Provided

IPD Sharing Statement

• Plan to Share IPD: No

• Responsible Party: University of Birmingham
• Study Sponsor: University of Birmingham
• Collaborators: GlaxoSmithKline

Investigators

• Principal Investigator: Gareth A Wallis, PhD; University of Birmingham

• PRS Account: University of Birmingham
• Verification Date: May 2016