Physical Activity Recommended to “improve” Bones
Exercise can improve bone health by increasing bone mass or by slowing or preventing age-related bone loss. Researchers continue to examine what type and how much exercise is necessary for bone health. Though leisurely levels of physical activity are a good starting point for beginning an exercise program, more moderate to vigorous levels of activity are necessary to challenge the skeleton. Exercise is also important for fall prevention, and certain types of exercise have been shown to lower fall risk. To realize the potential benefits of exercise, some precautions should be considered.
Precautions Before Exercise for Those With Osteopenia or Osteoporosis
Specific exercise recommendations tend to be difficult for those diagnosed with osteopenia or osteoporosis because of the limited number of research studies. If you have been diagnosed with osteoporosis, even if you have not yet experienced a fracture, you should avoid activities that put high stresses on the bone, such as jumping or deep forward-trunk flexion exercises (e.g., rowing, toe touches, and full sit-ups). A regular brisk walking program with hills as tolerated, combined with resistance training to improve balance and muscle strength, may reduce your fall risk. Exercise options may be limited for those with osteoporosis who are restricted by severe pain. It may be a good idea to begin exercise with a warm pool–based program, which, although not weight bearing, can improve flexibility and provide some muscle strengthening.
Exercise training after hip fracture and surgery have been found to significantly increase strength, functional ability, and balance as well as to reduce fall-related behavioral and emotional problems in elderly people (8). Recommendations for specific exercises should come from a physical therapist because the activity program needs to be individualized. Generally, these programs begin with a safe range of motion activities and muscle-strengthening exercises for the muscles surrounding the hips, trunk, pelvis, and lower body. Typically, exercise recommendations include avoiding high-impact activities such as basketball, volleyball, soccer, jogging, and tennis. These activities can damage the new hip or loosen its parts. Resistance exercises that cause hip abduction or adduction (swinging the leg from side to side) should generally be avoided initially to prevent dislocation of the new hip. Recommended exercises often include walking, stationary bicycling, and swimming.
Rehabilitation after vertebral fracture should include exercises to maintain proper posture while moving and exercises specifically aimed at strengthening the back extensor muscles (the muscles that help you stand up straight). Gentle yoga and tai chi are excellent activities to increase postural awareness and muscle strength and to improve balance. The goals of this type of program should be to reduce pain, improve mobility, and contribute to a better quality of life.
Physical Activity Recommendations
You have probably heard that exercise must be weight bearing to benefit your bones. Some of the first evidence that weight-bearing was important to the skeleton came from observations of bone loss in astronauts while in space when the invisible force of gravity on the skeleton is removed. Examples of this include immobilization (as when a limb is in a cast), long periods of bed rest (from prolonged illness), or being physically inactive. Unfortunately, the body quickly adapts to the reduced loads placed on it. Similarly, non–weight-bearing exercise, such as swimming and cycling, may not be an ideal exercise for bones because the body weight is supported by the water or the bike.
Is walking enough or should I jog?
Walking is often advocated as a weight-bearing exercise that is good for bones. True, walking is weight bearing, but unfortunately, most research studies of inactive women who begin a moderate walking program fail to find any effect of walking on bone mass. Survey studies show that women who walk fracture less often than women who are inactive. However, it is possible that walkers also engage in other healthy behaviors that could lower their fracture risks, such as better calcium intake or less smoking.
Only two walking studies out of many showed a positive effect of walking on spine bone mass (but not the hip). In these studies, however, women walked at a very fast race-walking pace of around 5 to 6 miles per hour (8 to 9.6 km/h), which is much faster than the usual 2 to 3 miles per hour (3.2 to 4.8 km/h) pace of most women. Because walking confers so many other benefits to the body, if you love walking, don’t stop! Increasing the intensity of your walking program to include bursts of very fast walking or walking briskly up hills, however, will burn some extra calories and keep your heart healthy as well as help your bones.
Studies of athletes have provided the basis for the design and testing of exercise interventions aimed to improve bone health. These interventions can better answer the question of what type and how much exercise strengthens bones. Bone Health recommends important lifestyle modifications, including exercise, to improve bone health. This information forms the basis for the exercise recommendations and sample programs outlined in this article.
The best program is one that incorporates multiple types of activity and applies the principles of training with bone health in mind. Next Table Exercises for Osteoporosis outlines the basic guidelines for exercise to promote bone health and overall fitness, and each exercise type is covered in more detail in the following sections. Exercise is site-specific. In other words, a particular bone must be directly stressed to receive benefits. A multimodal program can provide multiple benefits for musculoskeletal, cardiorespiratory, and metabolic health plus reduce the risk of injury.
Moderate to vigorous aerobic exercise can improve or maintain the bone mass of the hip and spine and has additional benefits to the cardiovascular, muscular, and nervous systems. To challenge the skeleton, the aerobic exercise should be weight bearing, although rowing may have particular benefit to the spine. Examples of weight-bearing aerobic exercises that have been shown to build or preserve bone density when done at moderate to vigorous intensity include aerobic dance, fast walking (5 miles per hour or faster, or 8 km/h), jogging (may begin with walking and intermittent jogging), stair climbing or bench stepping, tennis, and rowing.
The general recommendation for an aerobic exercise aimed to improve bone health is to reach a minimum target of 30 minutes of continuous moderate-intensity exercise five days each week for a total of 150 minutes. Another option is 75 minutes of vigorous-intensity exercise per week
(about 20 to 25 minutes three days each week), similar to the general public health recommendations for a physical activity .
To see more improvement, you can increase the amount of exercise by increasing the intensity, duration, or frequency. Generally, the upper range for effective aerobic exercise is 60 minutes of vigorous-intensity exercise five to seven days per week. Any more than this and your risk of injury or burnout increases.
If you already have been diagnosed with osteopenia or mild osteoporosis, a low- to a moderate-intensity exercise program is recommended to improve bone mass or prevent or slow further bone loss. If you have advanced osteoporosis or have had a recent fracture, this type of program may be too rigorous. Consult your healthcare provider to determine the level of activity suitable for your circumstances.
Exercise With Impact: Jumping!
Impact exercise, such as jumping, has been used for years by athletes to improve their muscular strength and power. Jump training may offer a quick and simple means to specifically improve bone mass at the hip, an area where fractures are especially debilitating. Jumping exercise works because it transmits forces up the skeleton and challenges bones in a way that they do not experience during normal daily activities. The skeleton responds by laying down more bone to make it stronger.
In general, studies have shown that women who perform jumping exercise, either alone or added to a program of another exercise such as walking or resistance training, maintain or improve their hip and spine bone mass. In one study, middle-aged and older women who regularly engaged in resistance exercise plus 50 to 100 jumps, three times per week, were able to increase or maintain hip bone mass; this even included women with low bone density. Unfortunately, jumping exercise alone does not appear to improve the bone health of the spine because the forces generated from landing are quite small by the time they reach the spine. Remember, to improve a bone, you must challenge it.
Jump training has not been studied extensively. In most studies, women have performed a variety of jumping routines, including simply jumping straight up and down ). When the height of the jump (jumping on and off small steps) or the weight of the person jumping is increased (jumping while wearing a weighted vest), the jump produces more force on the lower body. In general, doing 50 to 100 jumps in place three to five days per week in sets of 10 is recommended based on current research. Also keep in mind that bone responds slowly and is lost when you stop exercising, so a lifelong commitment is required for the best results.
Resistance or strength training can have a positive effect on bone the because the strong muscle contractions required to lift, push, or pull a heavyweight place stress on the bones. Resistance exercises can be done using weight machines, free weights such as dumbbells and barbells, weighted vests, elastic tubing, or elastic bands. In general, strength training using any means of applying sufficient resistance will maintain or slightly improve hip and spine bone mass.
Resistance training has an added benefit of strengthening muscles that are important for fall prevention and to perform strength-based tasks such as lifting groceries, rising from a chair, and climbing stairs. Strong leg muscles can also contribute to better balance and locomotion, which reduces the risk of falls. In addition, resistance exercise can help to lower blood pressure, improve cholesterol and triglyceride levels, and aid in weight reduction. There are many good reasons to include resistance training in your exercise plan.
Resistance exercise, like aerobic exercise, must be slightly rigorous to affect bone. Low-intensity resistance training like sculpting or toning exercises performed with light weights and for many repetitions generally does not help because this type of training doesn’t place enough force on the bones. See the sample exercise program for a beginning progression. This level gives you an opportunity to become familiar with resistance training and start to build a base of strength. Try to do most of your resistance training exercises while standing, which engages smaller muscles and is much more functional.
Resistance exercise is recommended for everyone, especially older adults who may have had some bone and muscle loss from age. Following proper guidelines, even 90-year-olds have safely performed resistance exercise. For complete details on resistance training, including specific exercises. Resistance exercise may be new for you, but it could make a real difference in your life, so give it a try.
Flexibility and Neuromotor Training
Stretching at least two to three days per week should be part of your exercise program to maintain or improve your flexibility and joint mobility. In addition, neuromotor exercises are also valuable. People with weak legs, poor balance, and gait problems are much more likely to fall than those who are strong, are stable, and move easily. Because falls are a leading cause of fracture, along with weak bones, focusing on fall prevention is key. For a list of proactive steps, you can take to prevent falls.
What strategies can be used at home to avoid falls?
Use these simple strategies to avoid a fall in the first place.
• Wear supportive, low-heeled shoes rather than walking in socks or slippers.
• Ensure that rooms are well lit.
• Use a rubber mat in the shower or bathtub.
• Use the handrails when going up and down stairs.
• Avoid the use of area rugs, but if you do have them, use skid-proof backing and secure corners to the floor or carpet underneath.
• Keep floors and walkways clutter free.
• Keep the phone and electrical cords out of the way.
• If needed, keep glasses handy rather than moving about with impaired vision.
• Realize the potential influence of medications on balance, and talk with your healthcare provider about any medications you are taking.
• Consider the fact that some hip fractures occur as a result of tripping over small pets.
For specific suggestions on functional (neuromotor) exercises. Some nontraditional forms of exercise (such as tai chi) have also been shown to reduce the risk of falls, suggesting that both muscle strength and the ability to transfer weight while in motion can maintain stability. Many research studies underscore how important strong muscles are for fall prevention.
Sample Exercise Program for Bone Health
A sample program of bone health exercise that incorporates multiple types of activity is shown in the figure below. Note that rest is included to allow the bone to be responsive to the next loading bout. This program would be appropriate for a beginner exerciser who is otherwise healthy and has no known orthopedic problems. If you have any concerns about your readiness to begin the exercise, consult with your healthcare provider.
As you can see, the sample program includes activities focused on aerobic and muscular fitness as well as flexibility. In addition, balance training is another consideration for fall prevention for anyone with osteoporosis. Each of these components is important to include in your exercise plan.
Weight-bearing aerobic activities can benefit your bones.