title: Resistance training over 2 years increases bone mass in calcium-replete postmenopausal women.
abstract: Understanding the stress/strain relationship between exercise and bone is critical to understanding the potential benefit of exercise in preventing postmenopausal bone loss. This study examined the effect of a 2-year exercise intervention and calcium supplementation (600 mg) on bone mineral density (BMD) in 126 postmenopausal women (mean age, 60 +/- 5 years). Assignment was by block randomization to one of three groups: strength (S), fitness (F), or nonexercise control (C). The two exercise groups completed three sets of the same nine exercises, three times a week. The S group increased the loading, while the F group had additional stationary bicycle riding with minimal increase in loading. Retention at 2 years was 71% (59% in the S group, 69% in the F group, and 83% in the C group), while the exercise compliance did not differ between the exercise groups (S group, 74 +/- 13%; F group, 77 +/- 14%). BMD was measured at the hip, lumbar spine, and forearm sites every 6 months using a Hologic 4500. Whole body BMD also was measured every 6 months on a Hologic 2000. There was no difference between the groups at the forearm, lumbar spine, or whole body sites. There was a significant effect of the strength program at the total (0.9 +/- 2.6%; p < 0.05) and intertrochanter hip site (1.1 +/- 3.0%; p < 0.01). There was a significant time and group interaction (p < 0.05) at the intertrochanter site by repeated measures. This study shows the effectiveness of a progressive strength program in increasing bone density at the clinically important hip site. We concluded that a strength program could be recommended as an adjunct lifestyle approach to osteoporosis treatment or used in combination with other therapies.
authors.affiliation: School of Public Health, Curtin University of Technology, Perth, Western Australia.
authors.forename: D
authors.initials: D
authors.lastname: Kerr
authors.forename: T
authors.initials: T
authors.lastname: Ackland
authors.forename: B
authors.initials: B
authors.lastname: Maslen
authors.forename: A
authors.initials: A
authors.lastname: Morton
authors.forename: R
authors.initials: R
authors.lastname: Prince
mesh_terms: D000368:Aged; D000886:Anthropometry; D015519:Bone Density / Q000187:drug effects; D001842:Bone and Bones / Q000378:metabolism / Q000502:physiology*; D002118:Calcium / Q000172:deficiency* / Q000627:therapeutic use; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000628:therapy; D017698:Postmenopause; D013997:Time Factors; D014891:Weight Lifting / Q000502:physiology*; D016474:Weight-Bearing
chemical_list: D002118:Calcium