Glycogen and Appetite
Study Details
Study Description
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.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
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N/A |
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Placebo Comparator: Control 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. |
Other: 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.
|
| Active Comparator: 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. |
Dietary Supplement: Exercise plus carbohydrate
A high carbohydrate drink to be consumed 1 hour prior to exercise and every 15 minutes during exercise.
|
| Experimental: 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. |
Dietary Supplement: Exercise plus niacin
A dose of niacin to be consumed 30 minutes prior to exercise, at onset of exercise and 30 minutes into exercise.
|
Outcome Measures
Primary Outcome Measures
- Difference in ad libitum energy intake [2 hours post exercise]
Difference between ad libitum energy intake (kcal) post exercise between trials
Other Outcome Measures
- Change in plasma GLP-1 concentrations post exercise [2 hours]
Incremental area under the curve of plasma GLP-1 concentrations
- Change in plasma leptin concentrations post exercise [2 hours]
Incremental area under the curve of plasma leptin concentrations
- Change in plasma insulin concentrations during exercise [1 hour]
Incremental area under the curve for plasma insulin concentrations
- Change in plasma non-esterified fatty acid concentrations during exercise [1 hour]
Incremental area under the curve for plasma non-esterified fatty acid concentrations
- Change in plasma glucose concentrations during exercise [1 hour]
Incremental area under the curve for plasma glucose concentrations
- Change in plasma lactate concentrations during exercise [1 hour]
Incremental area under the curve for plasma lactate concentrations
- Change in carbohydrate oxidation during exercise [1 hour]
Incremental area under the curve for carbohydrate oxidation
- Change in fat oxidation during exercise [1 hour]
Incremental area under the curve for fat oxidation
- Change in skin temperature during exercise [1 hour]
Incremental area under the curve for skin temperature
- Change in core body temperature during exercise [1 hour]
Incremental area under the curve for core body temperature
- Muscle glycogen utilisation [1 hour]
Difference in muscle glycogen utilisation during exercise between conditions
- Extra-muscular glycogen oxidation [1 hour]
Difference in extra muscular glycogen oxidation during exercise between conditions
- Difference in blood pressure between conditions [3 hours]
Difference in blood pressure between conditions
Eligibility Criteria
Criteria
Inclusion Criteria:
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Males aged 18-60 and premenopausal women
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Physically active (at least 30 minutes of exercise 3 times a week)
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Body mass index 18.0-30.0 kg·m-2
Exclusion Criteria:
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Weight instability (>5kg change in body mass over last 6 months)
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Restrained eater (e.g. limiting food intake, calorie counting)
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Current smoker
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Aversion or allergy to test meal foods
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Pregnant or lactating
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Amenorrhoea in women
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Any medical condition or medication that could introduce bias into the study (e.g., diabetes, CVD, lipid or glucose metabolism altering medications)
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Any cardiopulmonary condition prohibiting exercise testing
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Any contraindication to niacin or aspirin (e.g., diabetes, gout, clotting disorders, allergy to non-steroidal anti-inflammatory drugs)
Contacts and Locations
Locations
No locations specified.Sponsors and Collaborators
- University of Bath
Investigators
None specified.Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- EIRA1-7142