Bone is a dynamic tissue that undergoes constant change during our lifetime. As children and young adults, our bones generally become stronger and more resistant to fracture. From about age 25 until around 50 years old, the bone is breaking down and reforming at approximately equal rates, so bone mass and strength stay relatively constant. Later in life, bone loss overshadows bone development, so our bones become more fragile. Osteoporosis is a condition in which bones have become weakened to the point that the fracture risk is high. The spine, wrists, and hips are the areas most susceptible to osteoporotic fractures. Once these fractures occur, quality of life often is compromised. Although we will all lose bone if we live long enough, there are things we can do to increase bone health. In addition to eating a healthy diet rich in vitamin D and calcium, exercise is an important contributor to bone health.
RECOMMENDATIONS FOR CHILDREN
Because bone is developing during this period of life, it is important that children engage in activities that will aid bone formation. This does not necessarily mean structured activities; it can be the type of play that children often naturally choose if given the time and access to a safe environment (e.g., running, jumping, climbing). The U.S. Department of Health and Human Services (HHS) recommends that children and adolescents engage in 60 minutes or more of physical activity daily. The HHS guidelines further recommend that, on at least 3 days per week, part of the 60 minutes target bone-strengthening exercises such as running and jumping. The ACSM Position Stand "Physical Activity and Bone Health" recommends 10 to 20 minutes of high-intensity bone loading activities at least 3 days per week.
RECOMMENDATIONS FOR ADULTS
A combination of resistance exercise (i.e., lifting weights) and weight-bearing exercises, such as jogging, or playing tennis, or other sports that involve jumping, is recommended for adults. Thirty minutes or more of weight-bearing aerobic activities should be done 3 to 5 times per week. Resistance training should target major muscle groups and be completed 2 to 3 times weekly.
RECOMMENDATIONS FOR ADULTS WITH OSTEOPOROSIS
If you have osteoporosis, it is important to consult your physician for specific exercise recommendations. The amount, intensity, and types of activity you should do will be dependent on your individual needs. Many people with osteoporosis can safely engage in aerobic activities, resistance training, and balance training designed to address their special needs.
Exercise is an important part of developing and maintaining good bone health. Recommendations change over the life span, but for almost everyone, some form of exercise can be incorporated into the daily routine. It is important to remember that once bone is lost, it is very difficult to rebuild; therefore, make exercise a lifetime commitment.
Brought to you by the American College of Sports Medicine www.acsm.org