Purpose In childhood cancer survivors (CCS), high physical activity (PA) and low sedentary time may reduce risks of late-effects. PA behaviors and screen time, and how they relate to moderate-to-vigorous PA (MVPA) in CCS, are largely unknown. We examined PA behaviors and screen time, and their cross-sectional associations with MVPA.

Methods CCS from any cancer diagnosis (>= l year post-treatment), aged 9-16 years at study, were eligible in the international Physical Activity in Childhood Cancer Survivors (PACCS) study. PA behaviors (school transport, intensity-effort in physical education ("PE intensity"), leisure-time PA) and screen time were assessed by self-report, and MVPA by accelerometers (ActiGraph GT3X-BT). Multivariable linear regressions were used to assess associations between PA behaviors and screen time with MVPA.

Results We included 481 CCS (48% girls, mean age 12.2 years). Passive school transport (prevalence 42%) was associated with 10% lower MVPA/day (beta = 6.6 min, 95% CI 3.3-10.0), low PE intensity (prevalence 21%) with 16% lower MVPA/day (beta = 10.2 min, 95% CI 6.0-14.3), and low leisure-time PA (prevalence 34%) with 15% lower MVPA/day (beta = 9.4 min, 95% CI 1.0-17.7), compared to active school transport, high PE intensity and high leisure-time PA, respectively. High screen time was not associated with MVPA.

Conclusion Interventions aiming to increase PA behaviors rather than reducing screen time may be more efficient in promoting a healthy lifestyle in CCS through increased MVPA. Encouraging active transport, high PE intensity, and high leisure-time PA seems important in survivorship care.

Implications for Cancer Survivors Young CCS may benefit from engaging in active transport, high PE intensity, and high leisure-time PA.