Exercise Training
Conditions
Keywords
Metabolic adaptation, Energy expenditure, Exercise, Muscle
Brief summary
The primary aim of this proposal is to identify changes in the volume of highly metabolic organs (liver, kidneys, and brain) that occur as a physiological adaptation to exercise training and lower the resting energy expenditure. Secondary aims are to identify changes in the metabolic efficiency of muscle in low levels of physical activity and evaluate the effects on components of total daily energy expenditure including the sleeping metabolic rate (SMR) and diet induced thermogenesis (DIT).
Detailed description
Using a clinical trial type protocol, 16 overweight (body mass index: 25-30 kg/m2) men (n=8) and women (n=8) aged 21 to 45 years will exercise for 3 months in a moderate intensity regimen of 20 kcal/week/kg body weight that reflects current recommendations for weight management. The volume of various organs will be measured pre- and post-exercise intervention using magnetic resonance imaging (MRI). A cycling ergometer with a varied workload will be used to assess muscle metabolic efficiency. Changes in overnight SMR and 4 hours post breakfast DIT will be evaluated by whole human room indirect calorimetry (metabolic chamber). In addition, free-living Total Energy Expenditure (TEE) will be measured for ten days pre- and post-intervention by doubly labeled water.
Interventions
BEHAVIORALExercise training
The first phase of the study will comprise two weeks of control phase when participants will not engage in any exercise training but will be monitored for total daily energy expenditure and its components (REE, SMR, and DIT) and assessed volume of metabolic organs and skeletal muscle efficiency. Next, participants will start the active phase. In the first two weeks, participants will perform 150 - 200 min/week of a moderate intensity exercise so that they can adapt to the new regime and avoid injury. All exercise training will be monitored using heart rate sensor (HR) to track exercise adherence and HR range goals. Changes in daily non-exercise physical activity and sedentary behavior will be assessed for 10 days pre- and post-intervention by a tri-axial accelerometer. All study participants will be instructed to consume their habitual diet and to maintain the same caloric intake.
Sponsors
University of Colorado, Denver
Tel Aviv University
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Intervention model description
16 overweight (body mass index: 25-30 kg/m2) men (n=8) and women (n=8) aged 21 to 45 years will exercise for 3 months in a moderate intensity regimen of 20 kcal/week/kg body weight
Eligibility
Sex/Gender
ALL
Age
21 Years to 45 Years
Healthy volunteers
Yes
Inclusion criteria
Overweight \[body mass index (BMI) 25-30
Exclusion criteria
* Participation in another exercise or weight loss program in the last 6 months * Non-stable weight (\>±5%) over the past 6 months * Current regular exercise \> 1 hour per week * Smoking within the past 6 months * Being post-menopausal, breastfeeding, pregnancy, or having been pregnant within the past 6 months * Previous bariatric surgery * Cardiopulmonary disease (e.g., recent myocardial infarction or unstable angina) * Musculoskeletal or neuromuscular impairments that preclude exercise training * Having other health issues include cancer, diabetes, thyroid disease, hypertension, chronic renal failure, cognitive impairments * Use of drugs that potentially impact body metabolism.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| To examine long-term changes in the volume of highly metabolic organs (brain, liver, and kidneys) as an adaptive metabolic response to exercise training | Pre- and post 12 weeks of exercise intervention | The volume of various organs will be measured using magnetic resonance imaging (MRI). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| To evaluate the changes in skeletal muscle metabolic efficiency during non- exercise physical activity as an adaptive response to long-term exercise training | Pre- and post 12 weeks of exercise intervention | A cycling ergometer with a varied workload will be used to assess muscle metabolic efficiency |
| To determine the effect of long-term exercise training on changes in sleeping metabolic rate as an adaptive response . | Pre- and post 12 weeks of exercise intervention | Changes in overnight sleeping metabolic rate will be evaluated by whole human room indirect calorimetry (metabolic chamber) |
| To assess the effect of long-term exercise training on changes in diet induced thermogenesis as an adaptive response. | Pre- and post 12 weeks of exercise intervention | Changes in diet induced thermogenesis will be evaluated 4 hours post breakfast by whole human room indirect calorimetry (metabolic chamber) |
Countries
Israel
Outcome results
None listed