Skeletal response to resistance and impact training in prostate cancer survivors

Introduction: Androgen deprivation therapy (ADT) is associated with significant bone loss and an increase in fracture risk among prostate cancer survivors (PCS). We investigated whether impact + resistance training could stop ADT-related declines in bone mineral density (BMD) among PCS on ADT. Methods: We randomized 51 PCS (mean age, 70.2 yr) currently prescribed ADT to participate in 1 yr of impact + resistance training (Prevent Osteoporosis with Impact + Resistance (POWIR)) or in an exercise placebo program of stretching exercise (FLEX). Outcomes were proximal femur (total hip, femoral neck, and greater trochanter) and spine (L₁-L₄) BMD (gIcm^-2) and bone turnover markers (serum osteocalcin (ngImL^-1) and urinary deoxypyrodinoline cross-links (nmolImmol^-1 Cr)). Results: Retention in the 1-yr study was 84% and median attendance to supervised classes was 84% in POWIR and 74% in FLEX. No study-related injuries were reported. There were no significant differences between groups for average L₁-L₄ BMD or for BMD at any hip site. When examining individual vertebrae, POWIR has a significant effect on preservation of BMD (j0.4%) at the L4 vertebrae compared with losses (j3.1%) in FLEX (P = 0.03). Conclusion: Impact + resistance training was a safe and acceptable form of exercise for older PCS on ADT. Among our limited sample, POWIR did not appear to have a clinically meaningful effect on hip or spine BMD, but some evidence of skeletal adaptation to resistance + impact training in an androgen-deprived state was apparent. Future studies need to be conducted on a larger sample of patients and should consider modifications to POWIR that could further enhance loading across the spine and at the hip to preserve BMD at these clinically relevant sites.