Approximately 34 million Americans are at risk for developing osteoporosis due to low-bone density. Luckily, exercise can minimize your risk for osteoporosis, regardless of your age or previous activity level. However, you must perform the correct type of exercise -- and often enough -- for increased bone health. Understanding osteoporosis and benefits of exercise enables informed program design and improved bone health.
Osteoporosis Defined
Osteoporosis, also known as brittle bone disease, increases your risk of bone injuries and impaired mobility. Common risk factors include aging, smoking, inadequate calcium intake throughout life and a sedentary lifestyle. Typical sites for bone degeneration and osteoporotic injury include the spine, wrist, hips and shoulder. Often, a bone injury occurs before diagnosis transpires. However, X-ray scans can detect weak bones before the onset of osteoporosis.
Impact of Exercise
Like muscle, bone mass decreases with disuse. When muscle pulls on bones during activity, new bone formation occurs as a response. Minimal essential strain represents the least amount of strain needed for adaptation and generally equals any physical-activity level above an accustomed-to intensity. Therefore, a trained individual requires greater exercise intensity than a sedentary person. Intensity includes factors such as weightlifting load, walking speed or duration of your exercise session. Keep in mind, becoming sedentary after an exercise program will harm bone tissue built during the program.
Exercise Selection
Previously untrained individuals benefit from weekly walking. Weight-bearing activity occurs as you move your body mass through space. Younger or more experienced exercisers may perform weightlifting for improved bone health. Multi-joint weightlifting exercises, such as the squat, bench-press or lunge, apply force to multiple bones for increased benefit. In addition, squats and lunges load your spine -- a bone with high risk of deterioration. Vertebral bones, located at the spine, can experience increased density within eight to 12 weeks of weekly weight-bearing exercise. Remember, only utilized bones and muscles experience benefits of exercise.
Special Considerations for Women
Most victims of osteoporosis are women. Typically, women possess less bone mass than males. Additionally, hormonal changes during menopause increase the rate of bone loss. Although hormone therapy after menopause can help maintain bone tissue, bone loss continues at a reduced rate. As with men, weight-bearing exercise can prevent osteoporosis in females or reduce symptoms once osteoporosis occurs. As always, consult a doctor before starting an exercise program.
References
- National Osteoporosis Foundation: Bone Health Basics, Why Bone Health is Important
- American Council on Exercise, ACE Get Fit: Prevent Osteoporosis Now
- "ACE Personal Trainer Manual"; American Council on Exercise; 2003
- American Congress of Obstetricians and Gynecologists: What is Osteoporosis?
