Transcranial Direct-Current Stimulation Over the Primary Motor Cortex and Cerebellum Improves Balance and Shooting Accuracy in Elite Ice Hockey Players

Purpose : To investigate the effects of transcranial direct-current stimulation (tDCS) applied over the primary motor cortex (M1) and cerebellum on balance control and shooting accuracy in elite ice hockey players. Methods : Twenty-one elite ice hockey players underwent anodal tDCS over the M1 (a-tDCS M1 ), anodal tDCS over the cerebellum (a-tDCS CB ), concurrent dual-site anodal tDCS over the M1 and the cerebellum (a-tDCS M1+CB ), and sham stimulation (tDCS SHAM ). Before and after receiving tDCS (2 mA for 15 min), participants completed an ice hockey shooting-accuracy test, Pro-Kin balance test (includes stance test and proprioceptive assessment), and Y-balance test in randomized order. Results : For static balance performance, the ellipse area in the 2-legged stance with eyes open and the 1-legged stance with the dominant leg significantly improved following a-tDCS M1 , a-tDCS CB , and concurrent dual-site a-tDCS M1+CB , compared with tDCS SHAM (all P < .05, Cohen d = 0.64–1.06). In dynamic balance performance, the average trace error of the proprioceptive assessment and the composite score of the Y-balance test with the dominant leg significantly improved following a-tDCS M1 and concurrent dual-site a-tDCS M1+CB (all P < .05, Cohen d = 0.77–1.00). For the ice hockey shooting-accuracy test, shooting-accuracy while standing on the unstable platform significantly increased following a-tDCS M1 ( P = .010, Cohen d = 0.81) and a-tDCS CB ( P = .010, Cohen d = 0.92) compared with tDCS SHAM . Conclusion : tDCS could potentially be a valuable tool in enhancing static and dynamic balance and shooting accuracy on unstable platforms in elite ice hockey players.