Dose-Response Association between Exercise Intensity and Manual Motor Performance in Individuals with Down Syndrome: a Preliminary Study

This study was aimed at investigating the dose-response relationship between acute exercise and its effects on manual motor control mediated by the intensity of exercise in individuals with Down syndrome (DS). Participants were randomized into vigorous-intensity exercise (i.e., 75–85% of predicted MaxHR), moderate-intensity exercise (i.e., 50–75% of predicted MaxHR) or control groups. The exercise groups performed an incremental walking protocol on the treadmill and the control group watched a video for 20-min. Measures of grip strength and manual dexterity were tested pre- and post- intervention. A quadric trend was seen in grip strength, such that the moderate-intensity exercise was beneficial for grip force production. However, inconsistent with previous studies, neither a quadric trend nor a linear trend was evident in the performance of the Purdue Pegboard Test. Thus, a large sample size and brain imaging measures are needed to explore the underlying mechanisms involved in individuals with DS.