HIIT (High-intensity interval training) in Breast Cancer
By SUSAN GILCHRIST, M.D., M.S.
High-intensity interval exercise training (HIIT) is a form of exercise training that involves a series of short bursts of vigorous, near maximum effort (like a sprint) followed by short recovery periods. A HIIT program can take multiple different forms, such as variations on a 30 second cycling sprint to longer bouts on a treadmill with varying recovery times.
HIIT is of major interest to patients and exercise specialists in the oncology field, given HIIT training has been shown to improve fitness more quickly than traditional methods and HIIT can improve markers of metabolism (such as insulin sensitivity/diabetes). So, the question is – can this type of training be performed in breast cancer patients? Is it feasible and safe?
A recent article from our group, just published in the Medicine & Science in Sports and Exercise, showed that women who were overweight or obese and were at heightened risk for breast cancer significant improved their fitness utilizing a HIIT strategy compared to the control group. HIIT training consisted of 4 minutes of vigorous activity on a treadmill (e.g. walking up a steep incline) followed by 3 minutes of moderate activity x 4 cycles. This training was performed 3 times a week for 12 weeks. I was pleasantly surprised to see that the women in this trial really liked the HIIT training and they found it more interesting that just walking for exercise!
A second recent study in BMC Cancer was performed in women ~ 46 years of age with stage II or stage III breast cancer undergoing chemotherapy. In this 8-week HIIT training study, patient participated in a 3x a week cycling session that consistent of 7 x 1 minute intervals of vigorous activity followed by 2-min intervals of low-level activity. Warm and cool down was built into the sessions. Patients in the HIIT group improved their fitness to a greater extent than the control group. No adverse events were reported.
Bottom line – HIIT training appears to be feasible in study groups discussed above, though larger studies are needed. Of note, both studies were supervised and had a medical evaluation/clearance prior to the start of exercise training. Thus, if considering such a routine, talk to your doctor and make sure he/she is on board and this type of exercise is right for you! From my perspective, it is refreshing to see new studies published in the exercise oncology field that are testing novel exercise training strategies for breast cancer patients.
Hope this was helpful – Dr. G