Introduction Our aim was to assess differences in movement measures in attention-deficit/hyperactivity disorder (ADHD) vs. typically developing (TD) controls. Methods We performed meta-analyses of published studies on motion measures contrasting ADHD with controls. We also conducted a case–control study with children/adolescents (n = 61 TD, n = 62 ADHD) and adults (n = 30 TD, n = 19 ADHD) using the McLean motion activity test, semi-structured diagnostic interviews and the behavior rating inventory of executive function and Conners (parent, teacher; self) rating scales. Results Meta-analyses revealed medium-to-large effect sizes for actigraph (standardized mean difference [SMD]: 0.64, 95% confidence interval (CI): 0.43, 0.85) and motion tracking systems (SDM: 0.92, 95% CI: 0.65, 1.20) measures in differentiating individuals with ADHD from controls. Effects sizes were similar in studies of children/adolescents ([SMD]: 0.75, 95% CI: 0.50, 1.01) and of adults ([SMD]: 0.73, 95% CI: 0.46, 1.00). In our sample, ADHD groups differed significantly in number of head movements (p = 0.02 in children; p = 0.002 in adults), displacement (p = 0.009/p