Body Weight and Carb Metabolism

• Sponsor: University of Bath (Other)
• Overall Status: Recruiting
• CT.gov ID: NCT05330481
• Collaborator: University of Birmingham (Other)
• Enrollment: 20
• Location: 1
• Anticipated Duration (Months): 18
• Patients Per Site Per Month: 1.1

Study Details

Study Description

Brief Summary

Whilst theoretically, body size should influence the capacity for intestinal carbohydrate absorption and thus exogenous oxidation rates during exercise, there is currently little empirical evidence to support this hypothesis. Accordingly, current nutrition guidelines for carbohydrate intake during exercise do not take body mass into account. Therefore, there is a need to establish whether body mass is related to exogenous carbohydrate oxidation rates during exercise. If such a relationship is established, this would lay the foundation to revise the current sports nutrition guidelines regarding carbohydrate intake during exercise.

The aims of this study are, therefore, to: 1) establish whether larger individuals display higher rates of exogenous carbohydrate oxidation than smaller individuals; and 2) establish if such a difference can be explained by the higher absolute exercise intensity, and thus the energy demand of exercise. It is hypothesised that larger individuals will demonstrate higher exogenous carbohydrate oxidation rates than smaller individuals, and that this difference will be partly (but not completely) diminished when the absolute intensity of exercise is matched.

Condition or Disease	Intervention/Treatment	Phase
Exercise Metabolism	Other: Moderate-intensity (relative) exercise with glucose ingestion; Other: Moderate-intensity (absolute) exercise with glucose ingestion

Study Design

• Study Type: Observational
• Anticipated Enrollment: 20 participants
• Observational Model: Case-Control
• Time Perspective: Cross-Sectional
• Official Title: Exploring the Role of Body Mass in Exogenous Carbohydrate Oxidation Rates During Exercise
• Actual Study Start Date: Mar 1, 2022
• Anticipated Primary Completion Date: May 1, 2023
• Anticipated Study Completion Date: Aug 30, 2023

Arms and Interventions

Arm	Intervention/Treatment
<70 kg body mass Cyclists or triathletes with a body mass of less than 70 kg	Other: Moderate-intensity (relative) exercise with glucose ingestion; 120 minutes of cycling at 95% of lactate threshold ingesting 90 g/h of glucose
>80 kg body mass Cyclists or triathletes with a body mass of less than 80 kg	Other: Moderate-intensity (relative) exercise with glucose ingestion; 120 minutes of cycling at 95% of lactate threshold ingesting 90 g/h of glucose; Other: Moderate-intensity (absolute) exercise with glucose ingestion; 120 minutes of cycling at a power matched to participant in the <70 kg body mass group, ingesting 90 g/h of glucose

Outcome Measures

Primary Outcome Measures

1. Peak exogenous carbohydrate oxidation rate (g/min) [120 minute]

   Peak exogenous carbohydrate oxidation rate (g/min)

2. Total exogenous carbohydrate oxidation (g) [minutes 60-120 of exercise]

   Sum of exogenous carbohydrate oxidation in g

Secondary Outcome Measures

1. Total exogenous carbohydrate oxidation (g/kgFFM) [minutes 60-120 of exercise i]

   Sum of exogenous carbohydrate oxidation (g/kgFFM)

2. Whole-body carbohydrate oxidation rate (g) [minutes 60-120 of exercise]

   Sum of whole-body carbohydrate oxidation (g)

3. Whole-body carbohydrate oxidation rate (mg/kgFFM) [Sum ominutes 60-120 of exercise i]

   Sum of whole-body carbohydrate oxidation (mg/kgFFM)

4. Endogenous carbohydrate oxidation rate (g) [minutes 60-120 of exercise]

   Sum of endogenous carbohydrate oxidation (g)

5. Endogenous carbohydrate oxidation rate (mg/kgFFM) [minutes 60-120 of exercise]

   Sum of endogenous carbohydrate oxidation (mg/kgFFM)

6. Whole-body fat oxidation rate (g) [minutes 60-120 of exercise]

   Sum of whole-body fat oxidation (g)

7. Whole-body fat oxidation rate (mg/kgFFM) [minutes 60-120 of exercise]

   Sum of whole-body fat oxidation (mg/kgFFM)

8. Plasma lactate concentrations (mmol/L) [minutes 0-120 of exercise]

   Plasma lactate concentrations (mmol/L)

9. Plasma glucose concentrations (mmol/L) [minutes 0-120 of exercise]

   Plasma glucose concentrations (mmol/L)

10. Plasma non-esterified fatty acid concentrations (mmol/L) [minutes 0-120 of exercise]

    Plasma non-esterified fatty acid concentrations (mmol/L)

11. Plasma insulin concentrations (pmol/L) [minutes 0-120 of exercise]

    Plasma insulin concentrations (pmol/L)

12. Dietary carbohydrate intake (grams/day) [72-hour food diary in g/d]

    Dietary carbohydrate intake (grams/day)

13. Dietary sugar intake (grams/day) [72-hour food diary]

    Dietary sugar intake (grams/day)

14. Dietary fibre intake (grams/day) [72-hour food diary]

    Dietary fibre intake (grams/day)

15. Dietary fat intake (grams/day) [72-hour food diary]

    Dietary fat intake (grams/day)

16. Dietary protein intake (grams/day) [72-hour food diary]

    Dietary protein intake (grams/day)

17. Dietary energy intake (kiloJoules/day) [72-hour food diary]

    Dietary energy intake (kiloJoules/day)

18. Dietary energy intake (kilojoules/kilogram/day) [72-hour food diary]

    Dietary energy intake (kilojoules/kilogram/day)

19. Dietary carbohydrate intake (grams/kilogram/day) [72-hour food diary]

    Dietary carbohydrate intake (grams/kilogram/day)

20. Dietary sugar intake (grams/kilogram/day) [72-hour food diary]

    Dietary sugar intake (grams/kilogram/day)

21. Dietary fibre intake (grams/kilogram/day) [72-hour food diary]

    Dietary fibre intake (grams/kilogram/day)

22. Dietary fat intake (grams/kilogram/day) [72-hour food diary]

    Dietary fat intake (grams/kilogram/day)

23. Dietary protein intake (grams/kilogram/day) [72-hour food diary]

    Dietary protein intake (grams/kilogram/day)

Eligibility Criteria

Criteria

• Ages Eligible for Study: 18 Years to 60 Years
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

Inclusion Criteria:

• Able to cycle continuously for 2 hours at a moderate intensity

• VO2max of between 50-75 mL/kg/min

• Fat-mass index (determined by dual energy x-ray absorptiometry) < 5.5 kg·m-2

Exclusion Criteria:

• Diagnosed disorders of the gastrointestinal tract (e.g. crohn's, colitis etc.)

• People following a low-carbohydrate, high-fat diet

• Pregnant or lactating

• Diagnosed cardiovascular disease

• Possible symptoms of cardiovascular disease

• Diagnosis of diabetes of any type

• Hypercholesterolaemia (total cholesterol ≥ 6.2 mmol/L

• Hypertension (systolic blood pressure ≥140 mmHg or diastolic blood pressure ≥90 mmHg)

• Current smoker

• Family history of coronary artery disease (first-degree relative <60 years)

• Prevalence of vascular disease

• Autonomic neuropathy

• Kidney disease

• Diagnosed pulmonary disease (e.g. chronic obstructive pulmonary disease, asthma, interstitial lung disease or cystic fibrosis)

• Blood borne disease or infection

• Osteoporosis

• Osteoarthritis

• Blood clotting disorders

• Food intolerances/allergies (these may not specifically exclude you- please talk to the investigator)

• Sensitivity or allergy to anaesthetic

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Department for Health, University of Bath	Bath		United Kingdom	BA2 7AY

Sponsors and Collaborators

• University of Bath
• University of Birmingham

Investigators

None specified.

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

• Responsible Party: Javier Gonzalez, Reader (Associate Professor) in Human Physiology, University of Bath
• ClinicalTrials.gov Identifier: NCT05330481
• Other Study ID Numbers: 6632
• First Posted: Apr 15, 2022
• Last Update Posted: Apr 15, 2022
• Last Verified: Apr 1, 2022

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

Study Results

No Results Posted as of Apr 15, 2022