Exercise can improve bone health after cancer

Exercise for bone strength after cancer treatment.

Some cancer treatments, especially hormone therapies like aromatase inhibitors, can result in a loss of bone density. Fortunately, bone can respond and adapt to exercise. To build bone strength, resistance training (i.e., strength exercises) and impact loading (e.g., from hopping or jumping style exercises) are recommended. These place enough load onto the bones to stimulate bone strengthening. They also help build muscle, which in turn can improve bone strength (as muscle will place force on the bones as well) and prevent falls. Simple movements in one direction, rather than complex twisting movements, are often preferred because of the type of load they place on the bones.

Running can also place enough load onto your bones to encourage bone strengthening. When you run, your body absorbs approximately 2.5 times its body weight in force, which is sufficient force to encourage bone strengthening. Having said this, some runners, especially long-distance runners, do experience stress fractures in their lower limbs. This is more likely to occur when increasing running distances very quickly, running high total distances for a long time, not consuming enough energy and macronutrients to support recovery, and not allowing enough time for bone to recover and strengthen. The key takeaway here is to build up the amount of running you perform gradually, ensure that you are consuming a balanced diet that supports bone health, and ensure you get enough rest between runs.

Some of this advice may change when people have cancer that has spread to the bone (i.e. bony metastases). This does not mean you cannot exercise but may mean a more conservative approach without impact loading movements is best early on.

Guideline and reference: The Exercise and Sport Science Australia ‘Exercise medicine in cancer management’ guideline (here) emphasises resistance training for people with treatment induced bone loss, as well as impact loading and balance exercise.