Overweight and Obesity
Conditions
Keywords
time-restricted eating, high-intensity interval training, exercise, diet, body composition
Brief summary
This study will investigate the effects of seven weeks of time-restricted eating combined with high-intensity interval training compared with a control group on body composition in adults with overweight/obesity. Participants in the intervention group will complete the intervention remotely and will receive weekly follow-up through online platforms (telephone, video call). Before and after the intervention, 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
Maximal daily eating window of 10 hours and high-intensity interval training (three weekly, unsupervised, aerobic exercise sessions performed at \> 90 % heart rate maximum). Each exercise session will last for 33-38 minutes. Participants will receive digital follow-up once weekly. The intervention period will be seven weeks,
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 7 weeks of intervention | Change in total fat mass measured with bioelectrical impedance analysis |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Cardiorespiratory fitness | From baseline to after 7 weeks of intervention | Peak oxygen uptake at a maximum effort exercise test, measured in mL/min/kg and L/min |
| Physical activity level | From baseline to after 7 weeks of intervention | International Physical Activity Questionnaire, categorical score |
| Self-reported physical activity | 7 days at baseline, 7 days at start of intervention, 7 days at end of intervention. | Self-reported duration and intensity of daily physical activity during baseline week, first week of intervention, and last week of intervention, in metabolic equivalent of task (MET)/week |
| Diet intake | 7 days at baseline, 7 days at start of intervention, 7 days at end of intervention. | Online food diary during baseline week, first week of intervention, and last week of intervention, in kilojoules (kJ)/week |
| Sleep quality | From baseline to after 7 weeks of intervention | The Pittsburgh Sleep Quality Index questionnaire |
| Sleep duration | 7 days at baseline, 7 days at start of intervention, 7 days at end of intervention | Self-reported hours of sleep per night during baseline week, first week of intervention, and last week of intervention, average hours/night |
| Appetite | 7 days at baseline, 7 days at start of intervention, 7 days at end of intervention | Self-reported ratings of hunger/satiety on visual analogue scale upon waking and before bedtime during baseline week, first week of intervention, and last week of intervention, average hours/night |
| Blood glucose | From baseline to after 7 weeks of intervention | Fasting concentration of plasma glucose |
| Insulin | From baseline to after 7 weeks of intervention | Fasting concentration of plasma insulin C-peptide |
| Average glucose levels | From baseline to after 7 weeks of intervention | Glycated hemoglobin (HbA1c) |
| Blood Cholesterol | From baseline to after 7 weeks of intervention | Total fasting cholesterol in blood |
| HDL-cholesterol in blood | From baseline to after 7 weeks of intervention | Fasting high-density lipoprotein-cholesterol in blood |
| LDL-cholesterol in blood | From baseline to after 7 weeks of intervention | Fasting low-density lipoprotein-cholesterol in blood |
| Triglycerides in blood | From baseline to after 7 weeks of intervention | Fasting triglycerides in blood |
| Insulin sensitivity | From baseline to after 7 weeks of intervention | Homeostatic model assessment for insulin resistance (HOMA-IR): 1.5 + fasting plasma glucose (mmol/L) × fasting plasma insulin C-peptide (pmol/L) / 2800 |
| Body mass | From baseline to after 7 weeks of intervention | In kg, estimated with bioelectrical impedance analysis |
| Body fat-free mass | From baseline to after 7 weeks of intervention | In kg, estimated with bioelectrical impedance analysis |
| Visceral fat area | From baseline to after 7 weeks of intervention | In cm², estimated with bioelectrical impedance analysis |
| Systolic blood pressure | From baseline to after 7 weeks of intervention | Average of three measurements during rest in seated position, in mmHg |
| Diastolic blood pressure | From baseline to after 7 weeks of intervention | Average of three measurements during rest in seated position, in mmHg |
| Resting heart rate | From baseline to after 7 weeks of intervention | Average of three measurements during rest in sitting position, in beats/min |
Other
| Measure | Time frame | Description |
|---|---|---|
| Adherence to time-restricted eating | Seven weeks | Average number of days per week a daily eating window of 10 hours or less was achieved |
| Compliance to time-restricted eating | Seven weeks | Average daily eating window, self-reported in hours/day |
| Perception of intervention and digital follow-up | After seven weeks of intervention | Qualitative questionnaire after seven weeks of intervention |
| Sex differences | From baseline to after 7 weeks of intervention | Sub-analyses of sex differences in the effectiveness of the intervention |
| Adherence to high-intensity interval training | Seven weeks | Number of completed exercise sessions out of those prescribed, in percentage |
| Compliance to high-intensity interval training | Seven weeks | Exercise intensity measured with pulse sensor. Heart rate percentage of individual heart rate maximum. |
Countries
Norway
Outcome results
None listed