Overweight and Obesity
Conditions
Keywords
time-restricted eating, high-intensity interval training, exercise, diet, metabolic health, lifestyle intervention
Brief summary
This study will investigate the effects of 12 months periodised time-restricted eating combined with high-intensity interval training compared with a control group on fat mass in adults with overweight/obesity. Participants in the intervention group will complete the intervention remotely and will receive follow-up by telephone. Before randomisation, after 6 months and after 12 months, the investigators will measure the participants' body composition, physical fitness, fasting blood glucose and insulin, blood lipids, and blood pressure. Physical activity, diet, sleep quality, appetite, and adherence to the intervention will also be measured. Secondary sub-analyses of sex differences in the responses to the intervention will be performed.
Interventions
1-month intense periods of maximal daily eating window of 10 hours and high-intensity interval training (three weekly, unsupervised, aerobic exercise sessions performed at \> 90 % heart rate maximum), separated by 3-month maintenance periods of time-restricted eating on 5 days per week and minimum 1 HIIT session per week. Each exercise session will last for 33-38 minutes. Participants will receive digital follow-up once weekly during intense periods, and once monthly during maintenance periods. The intervention period will be 12 months in total.
Sponsors
Norwegian University of Science and Technology
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 50 Years
Healthy volunteers
No
Inclusion criteria
* Body mass index ≥ 27 kg/m² * Able to walk or ride a bike \> 60 min
Exclusion criteria
* On-going pregnancy * Lactation within 24 weeks of study commencement * High-intensity exercise ≥ 1/week * Habitual eating window ≤12 hours/day * Taking hypertension, glucose-, or lipid-lowering drugs * Body mass variation ≥ 4 kg three months prior to study commencement * Known diabetes mellitus (type 1 or 2) or cardiovascular disease * Working night shifts
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Total fat mass | From baseline to after 12 months | Change in total fat mass measured with bioelectrical impedance analysis |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Blood glucose | From baseline to after 6 months and after 12 months | Fasting concentration of plasma glucose |
| Total fat mass | From baseline to after 6 months | Change in total fat mass measured with bioelectrical impedance analysis |
| Insulin | From baseline to after 6 months and after 12 months | Fasting concentration of plasma insulin C-peptide |
| Average glucose levels | From baseline to after 6 months and after 12 months | Glycated haemoglobin (HbA1c) |
| Blood cholesterol | From baseline to after 6 months and after 12 months | Total fasting cholesterol in blood |
| LDL-cholesterol | From baseline to after 6 months and after 12 months | Fasting low-density lipoprotein-cholesterol in blood |
| HDL-cholesterol | From baseline to after 6 months and after 12 months | Fasting high-density lipoprotein-cholesterol in blood |
| Triglycerides | From baseline to after 6 months and after 12 months | Fasting triglycerides in blood |
| Cardiorespiratory fitness | From baseline to after 6 months and after 12 months | Peak oxygen uptake at a maximum effort test, measured in mL/min/kg and L/min |
| Insulin sensitivity | From baseline to after 6 months and after 12 months | Homeostatic model assessment for insulin resistance (HOMA-IR): 1.5 + fasting plasma glucose (mmol/L) x fasting plasma insulin C-peptide (pmol/L)/2800 |
| Body mass | From baseline to after 6 months and after 12 months | In kg, estimated with bioelectrical impedance analysis |
| Fat-free mass | From baseline to after 6 months and after 12 months | In kg, estimated with bioelectrical impedance analysis |
| Visceral fat area | From baseline to after 6 months and after 12 months | In cm2, estimated with bioelectrical impedance analysis |
| Systolic blood pressure | From baseline to after 6 months and after 12 months | Average of three measurements during rest in seated position, in mmHg |
| Diastolic blood pressure | From baseline to after 6 months and after 12 months | Average of three measurements during rest in seated position, in mmHg |
| Resting heart rate | From baseline to after 6 months and after 12 months | Average of three measurements during rest in sitting position, in beats/min |
| Physical activity levels | From baseline to after 6 months and after 12 months | International Physical Activity Questionnaire |
| Diet intake | During baseline week, after 4, 13, 30, and 50 weeks. | 3-day diet diaries (two weekdays and one weekend day) with online diet diary. |
| Sleep quality | From baseline to after 6 months and after 12 months | The Pittsburgh Sleep Quality Index questionnaire |
Countries
Norway
Outcome results
None listed