The aim of this randomised control trial is to investigate the role of fasted exercise on cardiometabolic health. Participants will be assigned to one of three conditions, fasted exercise, fed exercise and control (no exercise). Participants in the exercise groups will complete four weeks of moderate intensity cycling exercise, three times per week, either in the fasted or fed state according to their group assignment. Experimental trials involving anthropometric and cardiometabolic disease risk factor measurements as well as metabolic responses to a subsequent meal ingestion following exercise will be compared pre-intervention and post intervention.
The aim of this study is to investigate the effect of fasted exercise on cardiometabolic health and the potential mediatory role of sirtuins. The objectives are to investigate: 1. The effect of a single bout of fasted exercise on acute metabolic responses following a high fat meal. 2. The effect of four weeks of fasted exercise training on cardiovascular and metabolic disease risk factors. 3. The effect of four weeks of fasted exercise training on circulating levels and subcutaneous adipose tissue gene expression of SIRT1, SIRT3 and SIRT6. A randomised control trial will be conducted with volunteers allocated under the conditions of a) no exercise (control), b) fasted exercise training (FASTEX) and c) fed exercise training (FEDEX). The pre- and post-intervention visits will consist of 50 minutes of cycling at a moderate exercise intensity for both the FASTEX and FEDEX groups. The control group would not perform any exercise. The FASTEX group will perform the exercise in the fasted state, whilst the FEDEX and control groups will be fed a standardised breakfast meal one hour in advance of the exercise period. Following the exercise period, the participants will be fed a high fat meal and metabolic responses to the meal will be measured for four hours. Multiple blood samples will be obtained as well as a sample of subcutaneous adipose (fat) tissue. The FASTEX and FEDEX groups will then complete four weeks of moderate intensity continuous exercise training, either fasted or fed according to their group, on three days per week whilst the control group will maintain their normal sedentary lifestyle. All participants will return to the laboratory for post-intervention testing at the end of the four weeks with the same protocols and measurements as the pre-intervention testing.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
BASIC_SCIENCE
Masking
NONE
Enrollment
30
Four weeks of moderate intensity cycling exercise, three times a week without eating breakfast meal
Four weeks of moderate intensity cycling exercise, three times a week, after eating breakfast meal
Manchester Metropolitan University
Manchester, Greater Manchester, United Kingdom
RECRUITINGChanges in circulating concentrations of key metabolic markers following a high fat lunch meal
Serum concentrations of clinical chemistry blood analytes (glucose, triglycerides, cholesterol)
Time frame: 9 blood samples collected at pre-meal ingestion then every 30 min after ingestion for four hours
Changes in circulating concentrations of key metabolic markers during the experimental trial day
Serum concentrations of clinical chemistry blood analytes (glucose, triglycerides, cholesterol)
Time frame: 12 blood samples collected at 0 (baseline), 75 (pre-exercise), 125 (immediately post-exercise), 155 min (pre-meal ingestion) then every 30 min after ingestion for four hours
Area under the circulating concentration versus time curve (AUC) of key metabolic markers following a high fat lunch meal
Total responses of clinical chemistry blood analytes (glucose, triglycerides, cholesterol)
Time frame: 4.5 hours
Changes in cardiovascular and metabolic disease biochemistry risk factors
Fasted serum concentrations of clinical chemistry blood analytes (glucose, blood lipids, inflammatory markers)
Time frame: 4 weeks (pre and post intervention)
Changes in cardiovascular disease physiological risk factors
Systolic and diastolic blood pressure and calculation of mean arterial pressure using systolic and diastolic values
Time frame: 4 weeks (pre and post intervention)
Changes in concentration of sirtuin molecules
Serum concentrations of sirtuins
Time frame: 4 weeks (pre and post intervention)
Changes in sirtuin molecule gene expression
Adipose tissue gene expression of sirtuins
Time frame: 4 weeks (pre and post intervention)
Changes in sirtuin molecule tissue expression
Adipose tissue expression and cellular localisation of sirtuins
Time frame: 4 weeks (pre and post intervention)
Changes in cardiovascular and metabolic disease anthropometric risk factors
Waist circumference, hip circumference and waist:hip ratio
Time frame: 4 weeks (pre and post intervention)
Change in body composition
Body fat percentage measured using bioelectrical impedance analysis
Time frame: 4 weeks (pre and post intervention)
Change in body mass
Body mass in kilograms
Time frame: 4 weeks (pre and post intervention)
Change in substrate oxidation during the experimental trial day
Carbohydrate and fat oxidation through indirect calorimetry
Time frame: 17 measurements at 0 (baseline), 15 (post-breakfast meal period), 45 (30 min post-breakfast meal period), 75 (pre-exercise), every 10 min during exercise, 155 (pre-meal ingestion), then every 30 min for four hours.
Heart rate response to exercise
Heart rate during exercise in the experimental trial using telemetry
Time frame: At rest before exercise then every 5 min during 50 min cycle exercise
Perceived exertion
Rating of perceived exertion of exercise in the experimental trial using Borg scale
Time frame: Every 5 min during 50 min cycle exercise
Change in physical activity levels
Physical activity energy expenditure during the intervention period
Time frame: Daily for 4 weeks
Change in physical activity duration
Amount of time spent performing physical activity at different intensities (low, moderate, high) during the intervention period
Time frame: Daily for 4 weeks
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Change in energy intake
Energy intake using weighed food diary record during the intervention period
Time frame: Daily for 4 weeks
Change in dietary nutritional intake
Macronutrient (carbohydrate, fat, protein) composition of food intake using weighed food diary record during the intervention period
Time frame: Daily for 4 weeks