The impact of sensorimotor and cognitive capacity on the kinematic performance of instrumental activities of daily living across the lifespan

Abstract Background With advancing adult age, sensorimotor and cognitive capacity (e.g., muscular strength) are declining and limitations in instrumental activities of daily living (iADL) are frequently reported. The translation of individual capacity to iADL performance represents a significant research object not only to better understand everyday life behavior but also to apply preventive measures in time. Due to the submaximal nature of iADL, we aimed to identify transition points, beyond which associations between capacity and performance appear, i.e., iADL stop to be submaximal. Methods A set of sensorimotor and cognitive capacity tests and kinematic analyses of hand movements in different complex kitchen tasks were conducted in a sample of 95 healthy adults with an age span of 18 to 93a. An iADL score was derived from the kinematics using a principal component analysis. Transition point segmented regression analyses were applied to examine the association of capacity and the iADL score. Results Most tests reacted to ageing and (negative) outlier frequencies in capacity and, to a weaker extent, in kinematics increased with advancing age. Transition points were identified in most tests and confirmed our hypothesis but were generally high. The best iADL performance was observed in persons between 42 and 58a despite decreased capacity. Discussion It appeared that iADL can be limited by impaired capacity, but profit from experience that can compensate capacity losses to a certain degree. The high transition points point towards the need for early interventions long before subtle alterations in iADL performance become subjectively observable.