Parameters of Exercise to Prevent Osteoporosis

Osteoporosis, Postmenopausal Clinical Trial

— OSTEOPOROSISEX  

Official title:

Parameters of Exercise to Prevent Osteoporosis

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT04063813
• Other study ID #: HUM00007202
• Status: Completed
• Phase: N/A
• Start date: May 15, 2007
• Est. completion date: August 19, 2010

Study information

• Verified date: August 2019
• Source: University of Michigan
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The principal goal of this study is to determine parameters of walking in terms of peak mechanical vertical force, bout duration, and bout spacing that can preserve or increase bone mineral density (BMD) in postmenopausal women. Release of pulses of parathyroid hormone (PTH), growth hormone (GH), and of markers of bone resorption and bone formation will be used as indicators of the osteogenic effects of a short exposure to exercise. When secreted in pulsatile fashion, GH stimulates osteoblast proliferation, particularly in cortical bone (27, 28). Like GH, the pattern of PTH secretion determines the nature of its effect on bone. When it is secreted in pulsatile manner, PTH contributes to bone formation through activation of bone lining cells, differentiation of osteoprogenitor cells, and suppression of bone cell apoptosis .

Description:

A. Hypotheses and specific aims:

Specific aim 1. Measure plasma concentrations of anabolic hormones (parathyroid hormone (PTH) and growth hormone (GH), at sufficient frequency to define the area under the curve (AUC), and of markers of bone formation (osteocalcin, carboxyterminal propeptide of type 1 procollagen (CICP), and bone-specific alkaline phosphatase (ALKP)), and markers of bone resorption (immunoreactive carboxyterminal telopeptide of type I collagen (CTX)) after 40-minutes of treadmill exercise at the relative intensity of 125% of the ventilatory threshold (VT) corresponding to about 1.78 m/sec (4 miles/h), and two intensities of mechanical loading (724, and 1411 N), in healthy postmenopausal women.

Hypothesis 1. Bone formation, as assessed by increases in markers of bone formation and decreases in markers of bone resorption, will be higher in response to dynamic exercise at a level of mechanical loading that produces increased secretion of PTH and GH than to exercise at other loading intensities.

Specific aim 2. Measure plasma concentrations of anabolic hormones), at sufficient frequency to define the area under the curve (AUC), and of markers of bone formation as in specific aim 1, after two 20-minutes of treadmill exercise, separated by 7 h, at the relative intensity of 125% of the ventilatory threshold (VT) corresponding to about 1.78 m/sec (4 mi/h), and two intensities of mechanical loading (724, and 1411 N), in healthy postmenopausal women.

Hypothesis 2. A 7-hour interval separating the two bouts of exercise will have greater bone anabolic effect than the equivalent volume and intensity of exercise performed in a single bout.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 40
• Est. completion date: August 19, 2010
• Est. primary completion date: August 19, 2010
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Female
• Age group: 50 Years to 65 Years

Eligibility

Inclusion Criteria:

• Age 50 to 65 years if naturally post-menopausal, or age 47 if surgically postmenopausal

• Dual energy X-ray absorptiometry (DEXA) Z score above -1

• No endocrine or metabolic disease requiring medication except for hormonally corrected hypothyroidism

• No musculo-skeletal disabilities that would preclude treadmill walking

• Normal electrocardiogram (EKG) and heart health history

• BMI between 24 and 30

• Hematocrit above 32 %

• No hormone replacement therapy (HRT)

• Personal health provider's Release Letter

Exclusion Criteria:

• Age and BMI outside of the specified range

• Z score below -1

• Medication for presence of metabolic or endocrine disease

• Musculo-skeletal disabilities that would preclude treadmill walking

• Abnormal electrocardiogram (EKG) and heart health history

• Hematocrit below 32%

• Hormone replacement therapy

• Failure to conform to study protocol

Related Conditions & MeSH terms

• Osteoporosis
• Osteoporosis, Postmenopausal

Intervention

Behavioral:
• Experimental: 40 minute up trial

• Experimental: 40 minute down trial

• Experimental: Two 20 minute up trials

• Experimental: Two 20 min down trials

• Active Comparator: Sedentary trial

Locations

Country	Name	City	State
United States	Michigan Clinical Research Unit United States	Ann Arbor	Michigan

Sponsors (3)

Lead Sponsor	Collaborator
University of Michigan	National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), University of Wisconsin, La Crosse

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Ground reaction forces	Sum of pressures on mechanosensitive Novel-Pedar shoe insoles	During last 5 minutes of treadmill walking
Primary	Serum osteocalcin	Concentration of osteocalcin measured in serum samples	Hourly blood draws between 8:00 and 22:00 hours
Primary	Serum CICP (c-terminal propeptide of type 1 collagen	Concentration of CICP measured in serum samples	Hourly blood draws between 8:00 and 22:00 hours
Primary	Serum CTX (c-terminal telopeptide of type 1 collagen	Concentration of CTX measured in serum samples	Hourly blood draws between 8:00 and 22:00 hours
Secondary	Relative aerobic capacity	Percent of maximal aerobic capacity used during uphill and downhill exercise	1 day (measured throughout treadmill exercise bouts)
Secondary	Serum insulin	Concentration of insulin measured in serum samples	Hourly blood draws between 8:00 and 22:00 hours
Secondary	Serum cortisol	Concentration of cortisol measured in serum samples	Hourly blood draws between 8:00 and 22:00 hours
Secondary	Serum GH (growth hormone)	Concentration of GH measured in serum samples	Hourly blood draws between 8:00 and 22:00 hours
Secondary	serum PTH (parathyroid hormone)	Concentration of PTH measured in serum samples	Hourly blood draws between 8:00 and 22:00 hours