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

Dietary Modification Clinical Trial

Official title:

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

Clinical Trial Details — Status: Active, not recruiting

Administrative data

• NCT number: NCT02568592
• Other study ID #: ERN_15-0012
• Status: Active, not recruiting
• Phase: N/A
• First received: May 13, 2015
• Last updated: May 11, 2016
• Start date: March 2015
• Est. completion date: June 2016

Study information

• Verified date: May 2016
• Source: University of Birmingham
• Contact: n/a
• Is FDA regulated: No
• Health authority: United Kingdom: Research Ethics Committee
• Study type: Interventional

Clinical Trial 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.

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.

Recruitment information / eligibility

• Status: Active, not recruiting
• Enrollment: 16
• Est. completion date: June 2016
• Est. primary completion date: June 2016
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Female
• Age group: 18 Years to 45 Years

Eligibility

Inclusion Criteria:

• BMI >17.0 < 25 kg/m2

• Good General Health

• Accustomed to vigorous physical activity

• Run > 2 times per week

• V?O2max >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

Study Design

Allocation: Randomized, Intervention Model: Crossover Assignment, Masking: Open Label, Primary Purpose: Basic Science

Related Conditions & MeSH terms

• Dietary Modification

Intervention

Dietary Supplement:
• High Fat
High Fat - Carbohydrate (20%), Fat (65%), Protein (15%)
• Normal
Normal - Carbohydrate (50%), Fat (35%) and Protein (15%)
• 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.

Locations

Country	Name	City	State
United Kingdom	University of Birmingham	Birmingham	West Midlands

Sponsors (2)

Lead Sponsor	Collaborator
University of Birmingham	GlaxoSmithKline

Country where clinical trial is conducted

United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Rates of fat oxidation during exercise	Rates of fat oxidation to be measured via indirect calorimetry during 90 minutes of submaximal exercise	90 minutes of sub-maximal exercise	No
Secondary	5km running performance	Time to complete 5km on a treadmill	Immediately following measurement of Primary Outcome measure	No
Secondary	Change in plasma glucose concentration	Area under the plasma concentration versus time curve (AUC) of glucose	90 minutes sub-maximal exercise	No
Secondary	Change in Free Fatty Acid concentration	Area under the plasma concentration versus time curve (AUC) of Free Fatty Acid	90 minutes sub-maximal exercise	No
Secondary	Change in plasma glycerol concentration	Area under the plasma concentration versus time curve (AUC) of glycerol	90 minutes sub-maximal exercise	No