More Evidence that Exercise Improves Bone Strength

Several issues ago, we summarized a study from Sports Medicine that advocated weight bearing 
exercise (walking, running, step aerobics, etc.) for bone strength. (See "Maintain Strong 
Bones with Exercise" in the Sept. 1999 To Your Health.) Now comes another study, this 
time from
Medicine & Science in Sports & Exercise, that discusses the impact of resistance training 
on bone strength.

The authors in this study reviewed 10 years of literature on exercise and bone mineral 
density (BMD), paying particular attention to potential differences in type of exercise 
(weightbearing, aerobic, or resistance training) and BMD changes. 

The research reviewed suggested that exercise positively affects BMD in young and older 
adults, with the effects being specific to the muscles worked and the bones to which they 
attach. The authors also noted that "although aerobic exercise and weightbearing physical 
activity are
important... resistance training seems to have a more potent impact on bone density."

Resistance training is just about any exercise in which the muscles are forced to resist 
against an opposing force -- i.e., exercises involving free weights or weight machines, 
often with progression (increasing the resistance each set). Your chiropractor can tell 
you more about resistance training and outline an exercise routine appropriate to your 
needs.

For more information on sports and fitness, go to
http://www.chiroweb.com/find/tellmeabout/sports.html?n 

Layne JE, Nelson ME. The effects of progressive resistance training on bone density: a 
review. Medicine & Science in Sports & Exercise, 1999: Vol. 31, No. 1, pp25-30.