PURPOSE: Cancer-related fatigue (CRF) is a persistent, subjective sense of tiredness related to cancer or cancer treatment that interferes with usual functioning. CRF affects up to 96% of cancer survivors often times for many years following cancer treatment. We meta-analytically reviewed studies evaluating the efficacy of exercise as an intervention to reduce CRF among cancer survivors.
METHODS: Studies were included if they had: (1) an exercise intervention; (2) a self-report measure of fatigue, eg, Functional Assessment of Cancer Therapy Scale or Piper Fatigue Scale; (3) appropriate between or within subjects comparisons; and (4) sufficient statistical information to determine effect size (d+), calculated as the standardized mean difference of pre- and post-exercise CRF levels adjusted for baseline CRF and small sample sizes. All data were analyzed under fixed and random effects models.
RESULTS: Exercise interventions moderately reduced CRF (d+ = 0.28, 95% CI = 0.17, 0.41; Q(42) = 112.40, I2 = 62.60, p < 0.01). The characteristics of the exercise interventions that reduced CRF to the greatest levels were those: (1) of low intensity, aerobic exercise (b = -0.24, p < 0.01); (2) that included a resistance training component (b = 0.29, p < 0.01); (3) were supervised (b = 0.38, p < 0.01); and (4) of longer total intervention length (b = 0.37, p < 0.01).
CONCLUSION: Our findings suggest exercise interventions that are supervised, contain low intensity, aerobic exercise, resistance training, and long in total length are most efficacious in reducing CRF among cancer survivors.
Supported by: University of Connecticut Research Advisory Grant 433527