Weight Bearing or Resistance Exercise: Which is Best for my Bones?
A weight bearing exercise, otherwise known as impact exercise, is one where you hold your body up against gravity, loading your joints and muscles. Weight bearing exercise can be classified as low (i.e. walking, stair climbing), moderate (i.e. running, jumping, highland dancing, and hopping) or high-impact (i.e. landing from a high vertical jump as in basketball or gymnastics).
A resistance exercise is one where your body exerts muscular force against a physical load in order to move or maintain a position. These exercises result in stronger muscles. Examples include lifting weights, using resistance bands, holding a yoga pose, or using your own body weight to do push-ups and planks. Progressive resistance training involves a gradual increase in resistance over time as your muscles get stronger.
What about swimming?
Swimming is considered a non-weight bearing form of exercise as the buoyancy of water minimizes loading through your joints. The water acts as resistance to your movement, so swimming does provide a resistance workout.
What does this mean for my bones?
Studies have shown that a combination of weight-bearing and resistance exercise is best to promote bone strength. Either type alone may provide some benefit, and specific bone sites may benefit from one type more than another.
How bones get stronger..
Our muscles connect to our bones. When the muscles are forced to activate they exert a stress and strain on the bone. This forces the bones to adapt by strengthening in those areas which have been stimulated by the muscle. This is achieved through a highly intricate physiological process which promotes osteocyte activity (bone building) and reduces osteoclast activity (bone destruction).
The bare bones truth…
To promote bone health with exercise there are several key recommendations:
1) It is essential to provide forces in a variety of directions to your bones. For example, change your walking route regularly to challenge your muscles and bones in different ways (hills of various inclines), or do a variety of strengthening exercises like weight training and yoga. In other words, “change it up”.
2) Progressive muscle resistance training is recommended to promote maximum benefit to bone strength. When performing these exercises, your muscles should feel fatigued at the end of a set of exercises to maximize gains in muscle and bone strength. Muscle strengthening activities should be performed at least twice per week.
3) Daily physical activity spread across the day is important. Aim for 20-30 minutes of moderate physical activity each day, and avoid prolonged periods of sitting.
4) It is important to perform exercises with proper technique and at the correct intensity.
The above guidelines are appropriate for most, but not everyone, especially if you have had a fracture or have other medical conditions. Speak to an Osteoporosis physiotherapist prior to beginning an exercise program, and check in regularly, to ensure the exercises you are doing are right for you.