Clinical trial NCT01550536: Physical Activity and Basal Metabolic Rate in Postmenopausal Women
Official title: Aging and Basal Metabolic Rate in Postmenopausal Women: Effects of Long-Term and Short-Term Physical Activity
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Postmenopausal Metabolic Health
Keywords: basal metabolic rate
resting energy expenditure
menopause
physical activity
metabolic syndrome
Lead sponsor: University of California, San Diego
Sponsor class: OTHER
Collaborators: name: Wenner Gren
name: Sigma Xi
name: National Center for Research Resources (NCRR)
First posted: 2012-03-12
Enrollment: 49
Sex: FEMALE
Minimum age (years): 40
Maximum age (years): 120
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

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.


Eligibility criteria: Inclusion Criteria:

* naturally postmenopausal (i.e. non-surgically)/\> 1 year since last menstruation
* FSH \> 30 mIU/ml
* estradiol-17β \< 25 pg/ml

Exclusion Criteria:

* 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

Primary outcomes:
measure: Change in basal metabolic rate
timeFrame: baseline, 5, 10 and 16 weeks
Secondary outcomes:
measure: Change in fat-free mass
timeFrame: baseline, 5, 10 and 16 weeks
measure: Change in maximal aerobic capacity
timeFrame: baseline, 16 weeks
Other outcomes:
Locations:
city: La Jolla
country: United States
facility: La Jolla YMCA
state: California
city: La Jolla
country: United States
facility: UCSD Human Exercise Physiology Laboratory
state: California
city: San Diego
country: United States
facility: UCSD General Clinical Research Center
state: California
Study officials:
affiliation: University of California, San Diego
name: Andrew W Froehle, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Froehle AW, Ngo HT, Hopkins SR, Natarajan L, Schoeninger MJ. 2010. Relationship between physical activity, body composition and basal metabolic rate in postmenopausal women. Am J Hum Biol 22:252-253. [meeting abstract]
citation: Froehle AW, Ngo HT, Natarajan L, Schoeninger MJ, Hopkins SR. 2011. Short-term exercise does not elevate basal metabolic rate (BMR) in postmenopausal women in the absence of increased fat free mass (FFM). Am J Hum Biol 23:259. [meeting abstract]