Glycogen and Appetite

Not Applicable

Completed

• Conditions: Energy Intake
• Interventions: Other: Placebo; Dietary Supplement: Exercise plus carbohydrate; Dietary Supplement: Exercise plus niacin

• Registration Number: NCT05417659
• Lead Sponsor: University of Bath

Brief Summary

Obesity is the outcome of chronic excessive energy intake and reduced energy expenditure leading to energy imbalance. It is a risk factor for many preventable diseases such as metabolic disease and its consequences such as type 2 diabetes and cardiovascular disease. Sedentary adults have been shown to have an increased appetite in excess of energy requirements and adults who are more active are able to better regulate energy intake. It is thought that carbohydrate availability and specifically hepatic glycogen utilisation during exercise is a regulator of appetite. However, the majority of research so far does not support this theory, potentially due to research not examining the tissue-specific link between glycogen use and appetite. The aim of this study is to assess whether altering substrate utilisation during exercise by suppressing lipolysis influences GLP-1 levels and caloric intake post exercise. Additionally, the study will explore if there is a tissue specific link between substrate utilisation and post exercise energy intake and examine potential sex differences.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2022-05-17
• Study First Submitted QC: 2022-06-12
• Study First Posted: 2022-06-14
• Study Start: 2022-10-10
• Status Verified: 2023-10
• Primary Completion: 2024-03-15
• Study Completion: 2024-08-30
• Last Update Submitted: 2025-03-24
• Last Update Posted: 2025-03-27

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 15

Inclusion Criteria

• Males aged 18-60 and premenopausal women
• Physically active (at least 30 minutes of exercise 3 times a week)
• Body mass index 18.0-30.0 kg·m-2

Exclusion Criteria

• Weight instability (>5kg change in body mass over last 6 months)
• Restrained eater (e.g. limiting food intake, calorie counting)
• Current smoker
• Aversion or allergy to test meal foods
• Pregnant or lactating
• Amenorrhoea in women
• Any medical condition or medication that could introduce bias into the study (e.g., diabetes, CVD, lipid or glucose metabolism altering medications)
• Any cardiopulmonary condition prohibiting exercise testing
• Any contraindication to niacin or aspirin (e.g., diabetes, gout, clotting disorders, allergy to non-steroidal anti-inflammatory drugs)

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Control	Placebo	A placebo drink to be consumed 1 hour prior to exercise and every 15 minutes during exercise and placebo tablets to be consumed 30 minutes prior to exercise, at the onset of exercise and 30 minutes into exercise.
Exercise plus carbohydrate	Exercise plus carbohydrate	A high carbohydrate drink (1.6g/kg) to be consumed 1 hour prior to exercise and further drinks (0.2g/kg) every 15 minutes during exercise.
Exercise plus niacin	Exercise plus niacin	A dose of niacin (10mg/kg) to be consumed 30 minutes prior to exercise and two further doses (5mg/kg) at the onset of exercise and 30 minutes into exercise.

Primary Outcome Measures

Name	Time	Method
Difference in ad libitum energy intake	2 hours post exercise	Difference between ad libitum energy intake (kcal) post exercise between trials

Trial Locations

Locations (1)

Department for Health, University of Bath; 🇬🇧 Bath, United Kingdom