The effect of fasted and non-fasted cycling at different times of the day on appetite regulation, digestive function and metabolism in healthy overweight individuals

ISRCTN	ISRCTN11880065
DOI	https://doi.org/10.1186/ISRCTN11880065
Secondary identifying numbers	VJM_0878

Submission date: 07/12/2018
Registration date: 10/12/2018
Last edited: 13/09/2021

Recruitment status: No longer recruiting
Overall study status: Completed
Condition category: Nutritional, Metabolic, Endocrine

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Record updated in last year

Plain English Summary

Background and study aims
Growing interest in nutrition and the circadian system has produced many insights within recent years, with research suggesting circadian rhythms, nutrition and metabolism to be intimately linked. Intermittent fasting has become an increasingly popular intervention for metabolic health and combining intermittent fasting with exercise may lead to benefits for weight management. Therefore, the aim of this study is to investigate the effect of fasted versus fed exercise at different times of the day on gastrointestinal function, metabolic responses, and appetite responses, in overweight individuals.

Who can participate?
Males aged 18-40 years who are non-smokers and have a body mass index (BMI) class of 25-29.9 kg/m2 but otherwise healthy.

What does the study involve?
The participants will visit the laboratory on 5 occasions, once for a preliminary visit and on four other occasions to complete four separate experimental trials, two in the morning and two in the late afternoon. Experimental trials will consist of cycling exercise under 4 conditions; morning fed (AM-F), morning fasted (AM-NF), late afternoon fed (PM-F) and late afternoon fasted (PM-NF). Each experimental trial will last approximately 5.5 hours and begin at 0800 h for AM trials and 1500 h for PM trials. The AM-F and PM-F trials will consist of ingestion of a standardised breakfast meal one hour in advance of the exercise, whilst in the AM-NF and PM-NF trials, participants will not ingest the breakfast meal and remain fasted for the exercise. After the exercise participants will be provided with a standardised semi-solid meal. Regular breath and blood samples will be taken throughout the trials.

What are the possible benefits and risks of participating?
Participants will be able to receive data on their current aerobic fitness, body composition, and dietary analysis. Apart from this, there will be no immediate direct benefits to participants taking part. However, the results and participants’ experiences in the study will aid the research team in understanding the effect of fasting and exercise on the regulation of appetite and help develop further research on interventions that may help people improve their health. There is a small risk of muscle soreness and discomfort after each exercise session and a small risk of infection and discomfort from blood sampling.

Where is the study run from?
Manchester Metropolitan University.

When is the study starting and how long is it expected to run for?
December 2018 – September 2019

Who is funding the study?
Manchester Metropolitan University and The Physiological Society (research grant)

Who is the main contact?
Dr Adora Yau, a.yau@mmu.ac.uk

Contact information

Miss Victoria McIver
Public

NB443, Northumberland Building
Northumbria University
Newcastle upon Tyne
NE1 8ST
United Kingdom

Phone	+44 (0)191 227 3910
Email	Victoria.mciver@northumbria.ac.uk

Dr Adora Yau
Scientific

School of Healthcare Science, Faculty of Science and Engineering, Manchester Metropolitan University, Chester Street
Manchester
M1 5GD
United Kingdom

ORCID ID	0000-0001-9969-3764
Phone	+441612475504
Email	a.yau@mmu.ac.uk

Study information

Study design	Interventional, repeated measures design with randomised crossover
Primary study design	Interventional
Secondary study design	Randomised cross over trial
Study setting(s)	Other
Study type	Other
Participant information sheet	Not available in web format, please use contact details to request a participant information sheet
Scientific title	Implications of fasted cycling exercise on metabolic responses, gastrointestinal function, and appetite, in overweight individuals
Study acronym	FastExOverweight
Study hypothesis	1. Fasted exercise will result in differences in gastric emptying rate compared to fed exercise. 2. Fed or fasted exercise in the morning will result in differences in gastric emptying rate compared to fed or fasted exercise in the evening. 3. Fasted exercise will result in different gastrointestinal hormone responses, metabolic responses and appetite responses compared to fed exercise. 4. Fasted or fed exercise in the morning would result in differences in gastrointestinal hormone responses, metabolic responses and appetite responses compared to fasted or fed exercise in the evening.
Ethics approval(s)	Manchester Metropolitan University faculty of Science and Engineering Research Ethics and Governance Committee, 10/2018, ref. 0878.
Condition	Obesity
Intervention	The participants will complete four experimental trials in a randomised crossover design. Experimental trials will consist of 60 minutes of cycling under 4 conditions; morning fed (AM-F), morning fasted (AM-NF), late afternoon fed (PM-F) and late afternoon fasted (PM-NF). Each experimental trial will last approximately 5.5 hours and begin at 0800 h for AM trials and 1500 h for PM trials. Trials will be separated by a minimum of 7 days. The AM-F and PM-F trials will consist of ingestion of a standardised breakfast meal one hour in advance of 60 min of cycling exercise at approximately 60% peak maximal oxygen uptake, whilst in the AM-NF and PM-NF trials, participants will not ingest the breakfast and remain fasted for the same exercise. After the exercise in all four trials participants will be provided with a standardised semi-solid meal to ingest. Regular breath and blood samples will be taken throughout the trials. In the 24 hours following the end of each trial, participants will be asked to record their dietary intake. There will be no long term follow up following completion of the study.
Intervention type	Other
Primary outcome measure	1. Gastric emptying rate of a semi-solid meal that will be provided 30 minutes following the cessation of the cycling exercise will be measured using the 13C breath test method. 2. Breath samples will be collected every 15 min for a two-hour period. 3. Circulating levels of key gastrointestinal hormones and metabolic markers. Venous blood samples will be collected at baseline, post breakfast ingestion period, 1-hour post breakfast ingestion period (pre-exercise), immediately post 60-min cycle, 30 min post cycle (pre meal ingestion), then at 30 min intervals post meal ingestion for two hours. 4. Subjective feelings of appetite will be assessed using 100 mm visual analogue scales at baseline, post breakfast ingestion period, 30 min post breakfast ingestion period, pre-exercise, post exercise, pre semi-solid meal ingestion, then every 15 min post semi-solid meal ingestion for two hours. 5. 24h post trial energy intake using weighed food intake dietary record. 6. Substrate oxidation will be measured using a breath-by-breath gas analyser at baseline, post breakfast ingestion period, 30 min post breakfast ingestion period, pre-exercise, continuously throughout exercise, pre semi-solid meal ingestion, then every 30 min post semi-solid meal ingestion for two hours.
Secondary outcome measures	1. Salivary melatonin concentration at the start of the trials. 2. Ratings of perceived exertion using the Borg scale and heart rate using telemetry will be recorded pre-exercise and every 15 min during the exercise.
Overall study start date	28/02/2018
Overall study end date	24/05/2019

Eligibility

Participant type(s)	Healthy volunteer
Age group	Adult
Lower age limit	18 Years
Upper age limit	40 Years
Sex	Male
Target number of participants	12
Total final enrolment	12
Participant inclusion criteria	1. Male. 2. Aged 18-40 years. 3. Non-smokers. 4. Classified as overweight according to body mass index (BMI) class of 25-29.9 kg/m2 and body fat %. 5. Able and willing to comply with study procedures. 6. Willing to undertake required fasting duration, and with the capacity to provide informed consent 7. Free from injury prior to commencing the trials (6+months), with 1+ year free from any injury (such as, lower limb musculoskeletal injuries) that may have prevented and/or affected the participant. from performing cycling previously. 8. Classified as moderate or intermediate chronotypes according to the questionnaire of Waterhouse et al (2001).
Participant exclusion criteria	1. Regular medication or any known history of gastrointestinal, respiratory, cardiovascular, or endocrine disease. 2. Early circadian phase also known as extreme morning chronotypes and extreme evening chronotypes. 3. Involved in shift work and report any disturbances to their normal sleep-wake cycle during the two weeks prior to data collection. 4. Cannot consume the test meals due to intolerance's/dietary preferences.
Recruitment start date	12/12/2018
Recruitment end date	03/04/2019

Locations

Countries of recruitment

England
United Kingdom

Study participating centre

Manchester Metropolitan University

John Dalton Building, Chester Street
Manchester
M1 5GD
United Kingdom

Sponsor information

Manchester Metropolitan University
University/education

Faculty of Science and Engineering
John Dalton Building
Chester Street
Manchester
M1 5GD
England
United Kingdom

Phone	0161 247 2818
Email	Justine.Daniels@mmu.ac.uk
"ROR"	https://ror.org/02hstj355

Funders

Funder type

Other

Manchester Metropolitan University
Private sector organisation / Universities (academic only)

Alternative name(s): MMU
Location: United Kingdom

Physiological Society
Private sector organisation / Associations and societies (private and public)

Location: United Kingdom

Results and Publications

Intention to publish date	31/05/2022
Individual participant data (IPD) Intention to share	No
IPD sharing plan summary	Not expected to be made available
Publication and dissemination plan	Planned communication of results at a scientific conference. Planned publication in a high impact peer reviewed journal within 12 months of the completion of the study.
IPD sharing plan	The datasets generated during and/or analysed during the current study are not expected to be made available due to the conditions of the ethical approval granted for this study.

Editorial Notes

13/09/2021: Abstract and thesis added.
15/06/2021: The following changes were made to the trial record:
1. Contact details updated.
2. The intention to publish date was changed from 31/05/2020 to 31/05/2022.
13/09/2019: The following changes have been made:
1. The recruitment end date has been changed from 31/08/2019 to 03/04/2019.
2. The final enrolment number has been added.
3. The overall trial end date has been changed from 31/08/2019 to 24/05/2019.
19/12/2018: Internal review.
12/12/2018: The recruitment start date was changed from 17/12/2018 to 12/12/2018.