Unilateral balance training enhances neuromuscular reactions to perturbations in the trained and contralateral limb

Abstract

The aim of this study was to investigate the effect of unilateral balance training on the reactive recovery of balance for both trained and untrained limbs. Twenty-three subjects were randomly assigned to either a control group (CG) or a training group (TG). The latter performed six weeks of balance training for the right leg. The pre- and post-training measurements were based on single leg standing posture on a moveable force platform which moved 6 cm anteriorly. TG subjects were tested on the trained (TR) and untrained leg (UTR), whereas CG subjects were tested on the right leg (CTR). The center of pressure trajectory length (CPLEN) and average speed (CPSPD) as well as onsets of muscular activation and time to peak (EMGTP) from lower limb muscles were calculated and compared by a 2-way ANOVA (three legs×two training status). Muscular onsets were reduced after training for TR (∼19 ms, p<0.05) and UTR (∼17 ms, p<0.05) with no significant changes for CTR. No effects of training for CPLEN and medial-lateral CPSPD were found. Furthermore, the EMGTP of UTR was predominantly greater before training (∼17 ms, p<0.05). However, after training the EMGTP was similar among limbs. These results suggest that concomitant with improved balance recovery and neuromuscular reactions in TR, there is also a cross-education effect in UTR, which might be predominantly related to supraspinal adaptations shared between interconnected structures in the brain.

The cognitive complexity of concurrent cognitive-motor tasks reveals age-related deficits in motor performance

“…Prior to analysis, force and center of pressure data were low-pass filtered (50 Hz, zero-lag butterworth 4 th order). The average center of pressure speed and the variability of the center of pressure speed (calculated as the standard deviation of the center of pressure speed) were computed from the 30 s plantar pressure standing data 50 and were analyzed using custom scripts on MATLAB ® (R2016b, Mathworks Inc., Natick, MA USA).…”

Effects of wobble board training on single‐leg landing neuromechanics

“…It is believed that motor coordination is a key factor for injury prevention, as the gains in intermuscular coordination for landing may potentially reduce the likelihood of lower limb injuries. Wobble boards are simple and low‐cost devices widely used to investigate and improve balance and postural control . Previous studies have shown that such devices can provide fast improvement in balance performance with a long‐term retention, ultimately reducing the risk of ankle sprains by up to 50% .…”

Neuromuscular and Kinematic Adaptation in Response to Reactive Balance Training – a Randomized Controlled Study Regarding Fall Prevention

“…In contrast, conventional balance training (CBT) performed on unstable surfaces and convex devices has been validated to improve postural stability ( Granacher et al, 2006 ; Gruber et al, 2007a , b ; Taube et al, 2008 ; Freyler et al, 2014 ) and to elicit functional and neuromuscular adaptations beneficial for fall avoidance, such as augmented muscle strength ( Bruhn et al, 2006 ). This includes explosive force and rate of force development ( Gruber and Gollhofer, 2004 ; Taube et al, 2007 ) as well as modified muscle activity, such as increased activation or reduced co-contraction by means of improved muscle coordination, induced by neural adaptations within the central nervous system ( Granacher et al, 2009 ; Nagai et al, 2012 ; Oliveira et al, 2013 ; Behrens et al, 2015 ). These neuronal adaptations were specified by higher amplitudes and shorter latencies in the early reflex responses in the shank muscles, resulting in augmented ankle joint stiffness ( Granacher et al, 2006 ) and reduced fall frequency ( Madureira et al, 2007 ) in response to postural perturbations.…”