Doctor: “You have prostate cancer.”
Patient: “Doctor, that’s awful. What can I do to help it grow slower and feel better?”
Doctor: “Eat right and exercise.”
Patients: “How much exercise should I do?”
Doctor: “I don’t know.”
While the above is a fictitious discussion between doctor and patient, my guess is that similar discussions occur every day. When diagnosed with cancer, patients want to improve their lifestyle and clamor for any information their provider can give them. Unfortunately, most providers don’t know what advice to give. Even if the provider is knowledgeable and interested, discerning the literature and coming up with an answer to a straightforward question such as “how much exercise” is not an easy task. Into this void, steps the systematic review and meta-analysis by Lopez and colleagues.
Lopez and colleagues asked a simple question, “How much exercise is enough?” Sure, more is probably better, and we should indeed encourage our patients to exercise more rather than less. However, if it were that simple, we would not have the majority of people not meeting exercise guidelines. As such, while not trying to discourage patients who want to overachieve, in my experience, setting a minimum bar is very helpful for patients. To accomplish this, Lopez and colleagues performed a systematic review and meta-analysis using data from 18 trials involving 1112 men with prostate cancer. They focused on interventions involving resistance exercise and their effect on patient-reported outcomes.
It should be noted that 14 of the 18 trials were in men on androgen deprivation therapy (ADT) and most combined resistance exercise with aerobic exercise (n=8) or studied multimodal exercise (n=6). The authors showed that exercise vs. no exercise resulted in significant improvements in reducing fatigue and strong trends which approached but did not reach significance for decreasing depression and anxiety. Importantly, when the authors looked at how much exercise is needed, they found no associations between more exercise and better outcomes. Thus, whether the exercise intervention ranged from 8 weeks to 60 weeks, weekly reps ranged from 320 to 975, or whether the maximum intensity ranged from 60 to 85% - did not matter. The exercise was good and more was not better. Moreover, there were not even trends for more being better.
So, what does this study teach us? It teaches us exercise is good, though by now we should all know that. More importantly, we learn that for the outcomes of quality of life, more exercise is not better. Thus, for men having adverse quality of life effects from ADT (remember, 14 of the 18 trials they reviewed were men on ADT), even some resistance exercise is good. What remains to be determined is how much exercise is needed to reduce the metabolic sequelae of ADT and ultimately improve tumor control. While my money would bet on “more is better”, at least we can take comfort that for quality of life benefits, “Some exercise is enough”.
Written by: Stephen J. Freedland, MD, Division of Urology, Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, California
Read the Full-Text Article: What Is the Minimal Dose for Resistance Exercise Effectiveness in Prostate Cancer Patients? Systematic Review and Meta-Analysis on Patient-Reported Outcomes - Full-Text Article