To examine associations of physical activity (PA) and sedentary time (SED) with quality of life (QoL) in men on androgen deprivation therapy (ADT) for prostate cancer. A pooled analysis of 106 men on ADT was conducted. PA and SED were assessed using accelerometers. The Functional Assessment of Cancer Therapy (FACT) was used to assess self-reported QoL. Quantile regression examined the associations of QoL with PA and SED. Total time spent in SED was positively associated with FACT-General at the 50th (p = 0.010) and 75th percentile (p = 0.022). SED in ≥ 30-min bouts was inversely associated with FACT-General at the 50th (p = 0.025) and 75th percentile (p = 0.029). Breaks in SED were positively associated with physical well-being at the 75th percentile (p = 0.004). Light-intensity PA was positively associated with FACT-Prostate at the 25th percentile (p = 0.020). SED and PA were associated with QoL outcomes, but time in each varied across men reporting the poorest QoL compared to those in the highest QoL distributions.
