Slacklinetraining as balance training?

Improved postural control after slackline training is accompanied by reduced H-reflexes

Purpose

The purpose of the study was to analyze functional and neural adaptations after slackline training

Description

“Slacklining” represents a modern sports activity where people have to keep balance on a tightened ribbon. The first trials on the slackline result in uncontrollable lateral swing of the supporting leg. Training decreases those oscillations and therefore improves postural control. However, the underlying neural mechanisms are not known. Therefore, the present study aimed to highlight spinal adaptations going along with slackline training. Twenty-four subjects were either assigned to a training or a control group and postural control was assessed before and after the ten training sessions. Additionally, soleus H-reflexes were elicited to evaluate changes in the excitability of the spinal reflex circuitry. Trained subjects were able to maintain balance on the slackline for at least 20 seconds (p < 0.001) and reduced platform movements on the balance board (p < 0.05). The H-reflexes were significantly diminished (p < 0.05) while no changes occurred in the background EMG. The control group showed no significant changes. From a functional point of view the reflex reduction may serve to suppress uncontrollable reflex mediated joint oscillations. As the background EMG remained unchanged, presynaptic rather than postsynaptic mechanisms are speculated to be responsible for the changes in the Ia-afferent transmission.

Involved people

Martin Keller, Benedikt Lauber

Partners

Department Sport Science and Kinesiology, University of Salzburg, Austria
Christian Doppler Laboratory “Biomechanics in Skiing”, Austria

Additional information

In revision: Scandinavian Journal of Medicine and Science in Sports