Effects of physical activity on performance measures in older adult cancer survivors

Background Older adults who are long‐term survivors of cancer are vulnerable to developing mobility disability than noncancer controls; it is unknown if physical activity improves objective measures of lower‐extremity physical performance, such as the Short Physical Performance Battery (SPPB) and 400‐m walk, that are predictors of mobility disability in this population. Methods The Lifestyle Interventions and Independence for Elders (LIFE) study was a multicenter randomized trial that enrolled 1635 adults aged 70−89 years, of whom 371 (22.7%) reported a history of cancer and were included in this secondary analysis. Participants were randomized to health education or physical activity. End points included the SPPB and 400‐m walk. Results Randomization to physical activity, compared with health education, improved the SPPB score at 6 months (0.45 points [95% confidence interval (CI), 0.05–0.86]; p = .027), 12 months (0.43 points [95% CI, 0.02–0.83]; p = .039), and 24 months (0.45 points [95% CI, 0.04–0.87]; p = .031). Randomization to physical activity, compared with health education, improved the 400‐m walk speed at 6 months (0.042 m/s [95% CI, 0.017–0.066]; p < .001) and 12 months (0.036 m/s [95% CI, 0.011–0.060]; p = .004) but not 24 months (0.013 m/s [95% CI, −0.012 to 0.038]; p = .30). Moderate‐to‐vigorous intensity physical activity volume at 6 months mediated 25.3% (95% CI, 4.1–46.6 [ p = .019]) and 30.3% [95% CI, 10.3–50.4 [ p = .003]) of the effect of randomization on the SPPB score and 400‐m walk speed at 12 months, respectively. Conclusion Physical activity may improve lower‐extremity physical performance compared to health education in older adults who are long‐term survivors of cancer.