Wolfgang Kemmler, PhD
Archives of Physical Medicine and Rehabilitation
Volume 94, Issue 11 , Pages 2046-2053, November 2013

Abstract
Objective
To determine the effect of exercise frequency on various diseases and risk factors of the elderly.

Design
Retrospective analysis of a randomized controlled 18-month exercise trial.

Setting
University ambulatory group setting.

Participants
Community-dwelling women aged ≥65 years (N=162) in the area of Northern Bavaria.

Intervention
Mixed, intense aerobic, resistance, and balance protocol for 18 months. Subjects were retrospectively subdivided into 2 groups according to their effective attendance over 18 months (>1–

Main Outcome Measures
Bone mineral density (BMD), lean body mass, appendicular skeletal muscle mass by dual-energy x-ray absorptiometry, Framingham study-based 10-year coronary heart disease (CHD) risk, and number of falls by calendar method.

Results
Significant differences between the low-frequency exercise group (LF-EG) and the high-frequency exercise group (HF-EG) were observed for lumbar spine BMD (HF-EG, 2.4%±2.8% vs LF-EG, 0.3%±2.2%; P<.001) and proximal femur BMD (HF-EG, 2.4%±2.8% vs LF-EG, −0.5%±1.6%; P=.014), lean body mass (1.6%±3.4% vs 0.3%±2.6%, P=.053), and appendicular skeletal muscle mass (0.9%±4.5% vs −1.3%±3.2%, P=.011). No differences between both exercise groups were observed for 10-year CHD risk (−1.94%±4.14% vs −2.00%±3.13%; P=.943) and number of falls (0.95±1.36 vs 1.03±1.21 falls/person). Comparing the LF-EG with the less active control group (n=47), only nonsignificant effects for fall number (P=.065) and 10-year CHD risk (P=.178) were evaluated.

Conclusions
Although this result might not be generalizable across all exercise types and cohorts, it indicates that an overall exercise frequency of at least 2 sessions/wk may be crucial for impacting bone and muscle mass of elderly subjects.

Journal Abstract:  http://www.archives-pmr.org/article/S0003-9993(13)00422-X/abstract