There are many benefits to being physically active. For older women, one of those benefits may run as deep as the bones.
A recent study found that an increase in physical activity was associated with an increase in bone mineral density among older women, with the greatest increase found in the hip region.
Having a higher bone mineral density makes the bones stronger. A low bone mineral density, on the other hand, means a person is either at risk of or has osteoporosis — a condition that makes the bones weak and prone to fracture.
According to the study's authors, increasing physical activity through simple, daily tasks like housework can help to prevent decreases in bone mineral density.
This study was led by Jeffrey Muir of the Department of Clinical Epidemiology and Biostatistics at McMaster University in Canada. The research team examined the relationship between bone mineral density and regular physical activity in a group of older Canadian women.
The study included 1,169 woman aged 75 and older. Data was analyzed from the Canadian Multicenter Osteoporosis Study (CaMos).
Participants were asked to report their average level of activity for each week in the past year. Activities were categorized as moderate (such as housework or brisk walking), strenuous (such as jogging, bicycling or tennis) or vigorous (such as weight lifting). Participants were then asked to report how much time they spent each week performing those activities.
Bone mineral density was measured in five places: three different areas of the femur (thigh bone), the total hip and the lumbar spine (lower back).
Several factors were taken into account when analyzing the findings, including age, body mass index (a measure of height and weight), race and prescribed medications.
About 72 percent of women reported engaging in moderate physical activity for at least 4 hours per week.
The researchers found that for all of the sites measured (except for the lower back), a step increase in the amount of physical activity per week led to a significant increase in bone mineral density. A step increase would be going from 2-3 hours per week to 4-6 hours per week of physical activity.
The greatest increase in bone density was found in the hip region with an increase of 0.08 grams per cm3.
Physicians commonly recommend regular physical activity for patients at risk of osteoporosis, and the findings from this study support that recommendation.
As the researchers noted, any type of physical activity is important to prevent bone loss with the benefits primarily being seen in the hip region.
The study authors concluded that older women may be able to improve their bone density by simply increasing the amount of normal activity, like walking or housework, without having to begin a specific exercise routine.
"This study comes at a perfect time because doctors now have to warn people to stay away from calcium supplements since many studies now show they increase your risk for heart disease and do not increase bone density unless balanced with magnesium on a 1:1 ratio. Knowing that simple forms of exercise, and not the heavy workouts and weight lifting previously recommended, gives you a fighting chance to increase your bone density and bone health is a relief for many," Carolyn Dean, MD, ND, Medical Advisory Board Member of the non-profit Nutritional Magnesium Association, told dailyRx News.
"Simple exercise like walking, stretching, yoga and tai chi can all be safely done by people of any age and can easily fit into anyone's lifestyle. You may enjoy it so much you just want to do more," said Dr. Dean.
This study was published on August 23 in BMC Musculoskeletal Disorders.
The study authors reported no competing interests.