Liang studied women 20 to 25 years old who had mostly sedentary lifestyles. A study group that performed step aerobics three times a week for six months showed increases in bone density of up to 3.3 percent. A group that performed strength training increased bone density by up to 0.9 percent. Liang suggests that women mix high-impact exercise and strength training to build bone strength.
Young women can boost their bone strength with just six months of exercise, even if they've been sitting on the sidelines for a while.
The key is combining high-impact aerobics and strength training.
In a new study, step aerobics delivered the greatest gains in leg, spine, and heel bone density, while hip bones improved more with weight training.
In other words, do some of both types of exercise.
While you're at it, add some weight training exercises to build bones in the upper body.
The bone benefits add up quickly, says Michael T.C. Liang of California State Polytechnic University, in a news release.
Exercise amounted to a bone makeover for the women in Liang's study.
Like many Americans, they were sedentary, getting basically no exercise.
Liang and colleagues split the women into three groups.
One group (29 women) was assigned to do high-impact step aerobics three times a week for six months.
A third group (20 women) was allowed to stay idle, without any required exercise.
The exercisers got close supervision during their workouts.
The strength-training group did better in the hip area.
They had a gain of 0.9% in the density of the head of the hip bone, and a tiny hip density increase overall (0.1%).
Meanwhile, their heel bone density was up 0.1%, while leg bone density dropped by 0.4%.
Hip density dipped by 0.1% and head-of-the-hip density was down 0.7% in the aerobics group.
What about the women with no formal exercise program?
The bottom line: Mix high-impact exercise and strength training for best bone results, the study suggests.
The findings were presented at Experimental Biology 2005, a science conference in San Diego.