Effects of enhanced expectancies on execution and outcome variability of a sidestep cutting task in basketball players: a randomised controlled trial

The aim of this study was to investigate the effects of social-comparative feedback on cutting execution and cutting execution variability of basketball players in a sidestep cutting task, while throwing outcome is being tracked. A randomised controlled trial with two groups of male competitive basketball players (22.3 ± 5.3 years, enhanced expectancies (EE) and control (CTRL)) and three testing days was performed. A sidestep cutting task combined with throwing a basketball towards a target was included. All participants received feedback on their throwing accuracy after each block (n = 10 trials). Additionally, participants of the EE group received positive social-comparative feedback after each training block, irrespective of their actual performance, suggesting better performance compared to their peers. A one-week retention test without any feedback was used to assess learning effects in execution and execution variability (kinematics) with Statistical Parameter Mapping throwing outcome and throwing outcome variability with linear mixed model analyses. Although no significant differences regarding perceived competence were found, the EE group demonstrated greater outcome, outcome variability and execution variability during training (p <.05). This more variable behaviour seems necessary for exploring successful actions supporting learning and possibly decreasing ACL injury risk. Still, there were no significant differences between groups on immediate-post and retention test (p >.05), possibly due to high task complexity or the participants’ prior experience. The present data expand previous findings by indicating that (false) positive social-comparative feedback may support training of a complex sport task. Further investigation should determine an optimal amount and feedback schedule to elicit robust increases in expectancies.