Weight training increases bone density in young women, and may help women in the post menopausal years avoid bone loss and combal osteoporosis, according to a study reported in the August 1997 issue of the “Journal of Strength and conditioning Research. ” The fly exercise machine alone won't increase your bone density. Combine it with other resistance exercises of sufficient intensity and duration to keep your bones healthy and strong.
Your bones support your muscles, protect your internal organs and store calcium, which is essential for bone density. According to Heidi Weingart M.A., and Len Kravitz Ph.D., of the University of New Mexico, your bones are constantly breaking down and building up in a process called remodeling. One of the factors regulating remodeling is physical stress. Activities such as resistance training increase the physical stress on bones and may help maintain and increase bone density.
The Fly Exercise Machine
The fly exercise machine specifically works your chest and anterior deltoids as you move your arms in an wide arc toward the midline of your body. The physical stress is limited to your arms, shoulders and sternum, and the overall impact on your bone density is limited.
Moderate Resistance Training
A study at Oregon State University by the Bone Research Laboratory, Department of Exercise and Sports Science, looked at the effect of moderate-intensity resistance training on men and women ages 52 to 54. The subjects trained three times a week for 24 weeks using resistance machines such as the pec dec--- similar to the fly machine -- leg extension, leg curls, arm curl, chest press, shoulder press and lat pulldown. The exercise intensity was 40 to 60 percent of one-rep maximum for three sets of 10 to 13 reps. None of the subjects increased bone density of the spine and none of the women increased bone density of the hips.
Intense Resistance Training
Oregon State University also examined the effects of intense resistance training on men and women ages 52 to 54. The subjects did free-weight exercises such as barbell squats, deadlifts, barbell curls, chest presses and shoulder presses. Exercise intensity was 70 percent of one-rep maximum for three sets of eight reps. Both male and female subjects increased bone density in the hips. The women didn't increase bone density of the spine. The study concluded the higher intensity was not sufficient to to “offset low levels of estrogen in early postmenopausal women.”
Increasing Bone Density
If you're new to exercise, start with a comfortable weight that allows you to do three sets of 12 to 15 reps. As you get stronger, increase your weight to 60 percent of your one-rep maximum for three sets of 10 to 12 reps. Work up to 70 percent of your one-rep maximum for three sets of eight to 10 reps. According to the Sports Journal, an intense program of 70 percent and above of your one-rep maximum, performed at least twice a week for more than a year, may increase your bone density. Combine free-weight exercises such as barbell squats, deadlifts, dumbbell shoulder presses and barbell curls, with resistance machine exercises such as chest presses, pec dec flyes, lat pulldowns, triceps pushdowns leg presses, leg curls and calf raises.
- Journal of Strength and Conditioning Research: The Effects of Weight Training On Bone Density of Premenopausal, Postmenopausal, and Elderly Women: A Review
- University of New Mexico: Resistance Training and Bone Mass
- Calcified Tissue International: High Intensity Resistance Training: Effects on Bone In Older Men and Women
- The Sports Journal: Training To Improve Bone Density in Adults: A Review and Recommendations
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