Breast cancer treatments can lead to a host of other health issues. Among these is the loss of bone density, leaving us at risk for frailty and bone breaks. Fortunately, exercise – especially weight-bearing exercise – helps us build stronger bones. 

*Please talk with your healthcare provider before you begin a new exercise routine.

Cancer, treatment and bone density

There are many factors of breast cancer and its treatment that lead to bone density loss. Often the treatments themselves directly affect muscle and bones; in other cases, the effects are ancillary to treatments. Here are some ways in which treatment can affect our muscle and bone health:

  • Some of the side effects of our very necessary cancer treatments can affect our muscles and bones, making them weaker.
  • Steroids, which are so important in combatting nausea and fatigue right after chemotherapy treatments, can cause muscle weakness and decrease bone density over the long term.
  • The fatigue and sickness caused by treatment often lead us to be less active; being less active is also a factor that leads to muscle weakness and bone density loss.
  • Treatment-related appetite changes can cause us to not take in the nutrition we need to keep our muscles and bones healthy and strong.

Estrogen and bone density

Another important factor linked to decreased bone density is estrogen, which is a key component of bone density and bone health. This explains why osteoporosis becomes an issue for postmenopausal women among the non-cancer population: as estrogen levels decrease, so does bone density. The same is true for women who have been treated for breast cancer, especially for those with hormone-positive cancers who use hormone therapies, or who have had their ovaries removed or shut down. The resulting loss of estrogen can cascade down to a loss in bone density.

The importance of bone density and how exercise helps

Bone density is something to pay attention to. When our bones lose density, they become more brittle. This makes us more fragile; we become more likely to break bones if we fall. In extreme cases, even sudden movements can lead to breakage. However, much of that risk can be offset by engaging in an exercise routine.

According to Harvard Health Publishing, bones lose density at a rate of 1% per year beginning at around age 40. Among those who have had breast or ovarian cancer and their treatments, the rates are higher. When the loss is severe, the bones become fragile. 

Osteoporosis means “porous bones.” With osteoporosis, the body hasn’t produced enough new bone cells to replace the ones that die off naturally. In the US, about 8 million women and 2 million men have osteoporosis, putting them at greater risk for bone breakage. In fact, it is estimated that osteoporosis causes more than two million broken bones per year. These bones can break after a minor fall, a sudden movement, or even a sneeze.

Building bones

Did you know that bones grow throughout our lives? Our bones are living tissue and building them is a matter of using them. Just like using muscles causes them to get stronger, doing exercises that put stress on our bones helps them get stronger. 

Many studies have shown that strength training can slow bone loss or even build bone density, and some researchers are focusing particularly on people who have been treated for breast or gynecologic cancers. A 2016 study of breast cancer survivors, for example, found that a combined program of cardio and strength training significantly improved bone density after 26 weeks.

Types of exercise

Cardiovascular exercise: These exercises get our hearts pumping. They can (and usually are) weight-bearing, as we are bearing our own body weight. Among these are:

  • Walking
  • Jogging
  • Cycling
  • Dancing

Strength/Resistance training: These exercises not only strengthen our bones. They also help build stronger muscles, which protect us from falls. These exercises are also shown to reduce cancer-related fatigue, boost our moods, and improve our overall quality of life. Examples include:

  • Lifting free weights like dumbbells or heavy objects like cans
  • Using weight machines
  • Using resistance bands
  • Doing calisthenics like wall push-ups, leg squats, and crunches

Many styles of yoga offer a combination of cardio and strength/resistance training, and can be fun and rewarding, as they also promote relaxation and wellbeing. All of the forms of exercise can help improve our muscles and bone density, our joints, and our mood and wellbeing.

Making it real: creating a workout plan to keep your bones healthy

The study from 2016 involved an hour of exercise three days per week. The hour included 20 minutes of cardiovascular exercise, 25 minutes of circuit-style resistance training, and 15 minutes of core strengthening and stretching. 

If you were to create this kind of exercise routine at home, you could walk or cycle, or use a machine like an elliptical or stationary bike, for 20 minutes. Then you could use apps like Female Fitness or a 7-minute workout for the strength training portion and wind-down. 

Unite for HER offers online yoga classes and fitness programs for passport holders.

Sarah Murphy LPC, Unite for HER Staff Counselor