Physical Activity and Basal Metabolic Rate in Postmenopausal Women
- Conditions
- Postmenopausal Metabolic Health
- Interventions
- Behavioral: Resistance and aerobic exercise
- Registration Number
- NCT01550536
- Lead Sponsor
- University of California, San Diego
- Brief Summary
The primary purpose of this study is to expand research on the effects of physical activity on basal metabolic rate (BMR) in healthy postmenopausal women, and to further compare the effects of long-term habitual exercise to the results of a shorter-term (16 weeks) training program. The investigators will measure BMR by indirect calorimetry and normalize it across subjects for body size (fat free mass) and level of aerobic fitness (VO2MAX). Two groups will be compared: an intervention group (no previous participation in regular exercise, newly enrolled in this study's 16 week training program), and a long-term athlete group (have engaged in at least 5 hours of exercise per week for the past 10 years or longer). A secondary aim is to generate an equation for the prediction of BMR from fat free mass in physically active postmenopausal women, to be applied to hypotheses in biological anthropology. The investigators expect to find at baseline that, controlling for fat free mass and VO2MAX, the long-term group will have significantly higher BMR than the intervention group. At 16 weeks the investigators expect no change in BMR for the long-term group, while BMR will have increased in the intervention group. At the same time, the investigators expect to find that after completing the training regimen, the intervention group will have BMR similar to that of the long-term athletes.
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- Female
- Target Recruitment
- 49
- naturally postmenopausal (i.e. non-surgically)/> 1 year since last menstruation
- FSH > 30 mIU/ml
- estradiol-17β < 25 pg/ml
- smoker, abuser of alcohol/other drugs
- hypo- or hyperthyroid (serum TSH < 0.3 or > 5.5 microU/ml, respectively)
- underweight or severely obese (BMI < 18.5 or > 35 kg/m2, respectively)
- weight instability within the past six months (±> 5% of body weight)
- hormone replacement therapy within the past six months
- history of metabolic, respiratory or cardiovascular disease
- high blood pressure
- contraindication for maximal aerobic testing as determined by PAR-Q questionnaire and physician's examination
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Training Resistance and aerobic exercise Sedentary women who exercised \<2 hours per week and who had never engaged in a regular exercise program were enrolled in an exercise training intervention, following baseline measurements. See intervention below.
- Primary Outcome Measures
Name Time Method Change in basal metabolic rate baseline, 5, 10 and 16 weeks Basal metabolic rate is the energy expended at rest and under fasting conditions.
- Secondary Outcome Measures
Name Time Method Change in fat-free mass baseline, 5, 10 and 16 weeks Change in maximal aerobic capacity baseline, 16 weeks The maximal oxygen consumption achieved during a graded exercise test to exhaustion. Equipment: electronically-braked cycle ergometer. Participants were screened for CVD risk prior to testing by a physician. Lead II EKG was monitored during testing, and each test was overseen by a physician.
Trial Locations
- Locations (3)
La Jolla YMCA
🇺🇸La Jolla, California, United States
UCSD General Clinical Research Center
🇺🇸San Diego, California, United States
UCSD Human Exercise Physiology Laboratory
🇺🇸La Jolla, California, United States