Fig. 1

a Picture showing a participant training with the ARMEO® Spring. b Screen shot of the game Moorhuhn (“Crazy Chicken”) where the goal is to get as many points as possible by shooting the birds. Hitting smaller targets was rewarded with receiving more points. c Screen shot of the kinematic assessment “vertical catch 2D”. The parameters recorded are time to catch all 12 targets and path-ratio. Dividing the performed path (marked in red) by the ideal path (straight line between target and crosshairs in black) yields the dimensionless quantity path-ratio, which can at best reach a value of 1. d Depicts the procedure time line. Week 1 contains the baseline measurements and week 2 the measurements before and after the intervention. By comparing the differences between both weeks, this within-subject design enabled us to account for various factors such as the effect of other therapies, time of day, and repetition of the assessments