Comment on “Development of an accelerometer age- and sex-specific approach based on population-standardized values for physical activity surveillance: A proof of concept”

Device-based measurements are recommended to improve population-based physical activity (PA) surveillance.1,2 However, implementation remains challenging due to lack of consensus on analytical methods, and the most widely used “generic” (absolute intensity) cut-point approach has limited generalisability to population-level free-living data. Further, current methods generally fail to account for differences in people's physical capacity. With increasing age, an absolute intensity moderate-to-vigorous PA (MVPA) cut-point may be close to, or even exceed, an individual's maximal capacity. This results in PA recommendations being increasingly unattainable as people age. Activity that may be health-enhancing due to being at a relative moderate-to-vigorous intensity is overlooked due to not reaching the absolute MVPA cut-point.3,4 Recognizing this issue, the World Health Organization (WHO) recommends using relative PA intensities (i.e., adapted to their aerobic/functional capacity) for older adults.5