Effects of acute heat stress and regular exposure to hot environments on the oxidation of carbohydrates consumed during exercise

Not Applicable

Completed

Conditions: Acute heat stress and heat acclimation
Not Applicable

Registration Number: ISRCTN16394569

Lead Sponsor: niversity of Birmingham

Brief Summary: Not available

Detailed Description: Not available

Recruitment & Eligibility

Status: Completed

Sex: All

Target Recruitment: 18

Inclusion Criteria

1. Men or women
2. Aged 18 – 45 years
3. Compliance: understands and is willing, able and likely to comply with all study procedures and restrictions
4. Consent: demonstrates an understanding of the study and willingness to participate as evidenced by voluntary written informed consent
5. In good general health with no previous history of cardiometabolic disease
6. Body mass index in the range 18.5 – 27.5 kg/m²
7. Aerobically trained (i.e., participates in endurance-based exercise [e.g. cycling, running, rowing] at least three times per week)
8. Aerobic fitness: VO2max >45 ml/kg/min (men), >40 ml/kg/min (women)

Exclusion Criteria

1. Lidocaine allergy
2. Current participation in another scientific/clinical study
3. Pregnant or breastfeeding
4. Bleeding disorder/s
5. Current or recent smoker to include vaping (last 60 days)
6. Existence of food intolerances
7. Poor recent health as indicated in the general health questionnaire
8. Engage in uncommon eating practices (e.g. sustained periods of fasting)
9. Following a low dietary carbohydrate lifestyle

Study & Design

Study Type: Interventional

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Exogenous carbohydrate oxidation from a carbohydrate drink consumed during exercise, measured using a stable isotope tracer every 15 minutes during exercise

Secondary Outcome Measures

Name	Time	Method
1. Fluid absorption from a carbohydrate drink consumed during exercise, measured using the appearance of deuterated water in the bloodstream every 15 minutes during exercise after the 30-min timepoint<br>2. Self-rated gut comfort measured using visual analogue scales before and after exercise as well as every 15 min during exercise<br>3. Blood glucose regulation measured using analysis of plasma glucose concentrations every 15 min during exercise as well as before and after exercise<br>4. Muscle glycogen concentrations measured using biochemical analysis of glucose-6-phosphate after the breakdown of glycogen using hydrochloric acid just before and after exercise