Effects of slackline training on balance, jump performance & muscle activity in young children

The study investigated the effects of slackline training (rope balancing) on balance, jump performance and muscle activity in children. Two primary-school classes (intervention, n=21, INT: age: 10.1 (SD 0.4) y, weight: 33.1 (4.5) kg; control, n=13, CON: age: 10.0 (SD 0.4) y, weight: 34.7 (7.4) kg) participated. Training was performed within 6 weeks, 5 times per week for 10 min each day. Balance (static and dynamic stance), countermovement jumps, reverse balancing on beams (3, 4.5 and 6 cm width), slackline standing (single- and double-limb) and electromyographic activity (soleus, gastrocnemius, tibialis anterior) were examined. INT significantly improved single- and double-limb slackline standing (double limb: 5.1 (3.4) s-17.2 (14.4) s; right leg: 8.2 (5.8) s-38.3 (36.0) s; left leg: 10.6 (5.8) s-49.0 (56.3) s; p<0.001; 0.17<ηp²<0.22). Reduced left-leg dynamic sway (-20.8%, p=0.06, ηp²=0.10), improved 4.5 cm balancing (+18.5%, p=0.08, ηp²=0.10) and decreased muscle activity during slackline standing for the mm. soleus (-23%, p=0.10, ηp²=0.18) and tibialis anterior (-26%, p=0.15, ηp²=0.14) was observed for INT. Jump performance remained unchanged (p=0.28, ηp²=0.04). In conclusion, daily slackline training results in large slackline-specific balance improvements. Transfer effects to static and dynamic stance, reverse balancing or jumping performance seemed to be restricted.