Carbohydrate Intake and Gut Hormone Release During Exercise

Obesity Clinical Trial

Official title:

Carbohydrate Intake and Gut Hormone Release During Exercise

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT04019418
• Other study ID #: 18HH4889
• Status: Completed
• Phase: N/A
• Start date: February 21, 2019
• Est. completion date: February 12, 2020

Study information

• Verified date: February 2022
• Source: Imperial College London
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

It is well known that following a single session of moderate-to-high intensity exercise individuals experience a temporary suppression of hunger and a delay in the commencement of eating. This effect is believed to be due to changes in blood concentrations of specific hormones released from the gut that influence appetite.

Individuals undertaking physical activity often consume foods immediately before exercise in order to improve their performance. However, it is currently unknown whether this eating practice influences the gut hormone response to exercise as well as how hungry an individual feels post-exercise.

Therefore, the aim of this study is to investigate the effect of consuming a sugary (carbohydrate) drink immediately before starting an exercise session on the concentration of these gut hormones as well as the amount of food eaten in the hours following exercise completion.

Description:

It is well established that following an acute bout of moderate-to-high intensity exercise individuals experience a transient suppression of hunger and a delay in the commencement of eating - a phenomenon referred to as exercise-induced anorexia. Acute exercise modulates the concentrations of gut hormones known to influence satiety, including the anorexigenic hormones glucagon-like peptide 1 (GLP-1) and peptide tyrosine tyrosine (PYY), as well as the acylated form of the orexigenic hormone ghrelin. These alterations in gut hormone concentrations have consequently been hypothesised to play a key role in exercise-induced anorexia.

Despite suppressing hunger and delaying eating, acute exercise does not appear to alter short-term energy intake in the immediate hours following exercise completion. The absence of a compensatory response therefore creates an energy deficit capable of inducing weight loss. Strategies that augment the gut hormone response to acute exercise may thus increase the potency of exercise as a weight-loss tool.

Research investigating the effect of exercise on appetite has frequently utilised participants in a fasting state. Undertaking exercise in this physiological condition contradicts current practices, as athletes often consume a carbohydrate source immediately prior to exercise in an attempt to maximise performance. It is currently unknown as to whether the consumption of carbohydrate during this period may further enhance the gut hormone response to exercise, and thus research into a potential additive effect is warranted.

High-intensity exercise increases sympathetic nervous system activity and catecholamine release. Catecholamine concentrations are negatively correlated with acylated ghrelin concentrations and may directly stimulate GLP-1 and PYY release via activation of β-receptors located on L-cells. The decrease in gastric emptying rate that is observed during high-intensity exercise is also attributed to this increase in sympathetic activity. Consequently, an increase in sympathetic nervous system activity has been postulated as a key mechanism underlying exercise-induced changes in gut hormone concentrations. However, to our knowledge, no study has directly measured the relationship between sympathetic nervous system activity and anorexigenic gut hormone release during exercise.

Therefore, the aim of this study is to examine any potential additive effects of carbohydrate ingestion immediately prior to exercise on gut hormone release and post-exercise appetite suppression. Furthermore, this study will look to investigate the mechanisms underlying changes in gut hormone concentrations experienced during exercise.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 12
• Est. completion date: February 12, 2020
• Est. primary completion date: February 12, 2020
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Male
• Age group: 18 Years to 40 Years

Eligibility

Inclusion Criteria:

• Male

• Age between 18-40 years (inclusive)

• Body mass index (BMI) of 18-30 kg/m2

• Willingness and ability to give written informed consent and willingness and ability to understand, to participate and to comply with the study requirements

Exclusion Criteria:

• Abnormal ECG

• Screening blood results outside of normal reference values

• Current smokers

• Current or history of substance abuse and/or excess alcohol intake

• Diabetes

• Cardiovascular disease

• Cancer

• Gastrointestinal disease e.g. inflammatory bowel disease or irritable bowel syndrome

• Kidney disease

• Liver disease

• Pancreatitis

• Started new medication within the last 3 months likely to interfere with energy metabolism, appetite regulation and hormonal balance, including: anti-inflammatory drugs or steroids, antibiotics, androgens, phenytoin, erythromycin or thyroid hormones.

• Participation in a research study in the 12 week period prior to entering this study.

• Any blood donation within the 12 week period prior to entering this study

Related Conditions & MeSH terms

• Obesity

Intervention

Dietary Supplement:
• Maltodextrin (carbohydrate)
A drink containing 300ml of water and 75g of maltodextrin

Other:
• Exercise
30 minutes on a cycle ergometer working at 75% VO2 max
• Rest
30 minutes laying on a bed
• Water
A drink containing 300ml of water

Locations

Country	Name	City	State
United Kingdom	Imperial Clinical Research Facility	London

Sponsors (1)

Lead Sponsor	Collaborator
Imperial College London

Country where clinical trial is conducted

United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Changes in GLP-1 concentration	Changes in GLP-1 concentration between exercise and resting conditions, and between carbohydrate and control conditions	During the study visit, 165 minutes
Primary	Changes in PYY concentration	Changes in PYY concentration between exercise and resting conditions, and between carbohydrate and control conditions	During the study visit, 165 minutes
Primary	Changes in acylated ghrelin concentration	Changes in acylated ghrelin concentration between exercise and resting conditions, and between carbohydrate and control conditions	During the study visit, 165 minutes
Secondary	Changes in energy intake	Differences in energy intake at an ad libitum meal between exercise and resting conditions, and between carbohydrate and control conditions	During the study visit, 165 minutes
Secondary	Changes in Energy expenditure	Differences in energy expenditure between exercise and resting conditions, and between carbohydrate and control conditions.	During the study visit, 165 minutes
Secondary	Changes in energy balance	Differences in energy balance between exercise and resting conditions, and between carbohydrate and control conditions.	During the study visit, 165 minutes
Secondary	Glucose homeostasis	Changes in glucose homeostasis between exercise and resting conditions, and between carbohydrate and control conditions.	During the study visit, 165 minutes
Secondary	Changes in subjective nausea	Changes in subjective feelings of nausea as measured by visual analogue scales between exercise and resting conditions, and between carbohydrate and control conditions. Visual analogue scales will range from 0 mm to 100 mm with a higher score indicating a higher degree of nausea.	During the study visit, 165 minutes
Secondary	Changes in subjective appetite	Changes in subjective feelings of appetite as measured by visual analogue scales between exercise and resting conditions, and between carbohydrate and control conditions. Visual analogue scales will range from 0 mm to 100 mm with a higher score indicating a higher degree of fullness.	During the study visit, 165 minutes