Breast Cancer and the Athlete: Part 2, Exercise Volume

By SUSAN GILCHRIST, M.D., M.S.

Last week we talked about the importance of accurately measuring heart rate in order to guide exercise training intensity goals. Exercise intensity is one aspect of training that is necessary to improve overall fitness. Immediately after surgery or during chemotherapy, intensity can be compromised in order to protect the body and allow for healing. That being said, being fit is a combination of both exercise intensity and volume. Exercise volume is the minutes in the exercise bout as well as the frequency of exercise training per week.

FITNESS = INTENSITY (% peak exercise heart rate) X VOLUME (bout length [min] x frequency [# sessions/wk]). 

When I approach patients regarding their exercise volume, the first discussion point is around exercise history. Prior to being diagnosed with breast cancer, I asked patients how many minutes of exercise and how many times a week they trained. When they trained, I ask what percent was aerobic exercise versus resistance exercise. 

Exercise volume is very personal. Through my questioning, I learn how much time they have in a week to commit to exercise, what types of exercise they love doing and have been doing without injury, whom they like to exercise with, and what they feel works and doesn’t work to keep them fit (believe me, an athlete knows).

Once I know their usual aerobic training bout length (in minutes), I work with them to maintain that length but make sure it is at their target heart rate intensity. In some cases, the specifics of exercise need to change to keep in the correct prescribed intensity (biking on stable terrain and with modest incline versus hill climbing) for each exercise bout.  

Next, we discuss frequency of exercise sessions per week. Athletes train most days of the week, though with the side-effects of breast cancer treatment, this may not be realistic. Thus, I tell my patients to listen to their body regarding their readiness for exercise training each day. Most of my patients get into a rhythm of good and bad days during the weeks of chemotherapy and can plan their training accordingly. Once chemotherapy is completed, training days usually revert to normal if their schedule allows.

Next time, we will wrap up exercise training for an athlete…

In the meantime, tell me more about your training during chemotherapy. Specifically, what days did you feel the best to exercise and what exercises work best for you?