Specific Stimuli Induce Specific Adaptations: Sensorimotor Training vs. Reactive Balance Training

Abstract

Typically, balance training has been used as an intervention paradigm either as static or as reactive balance training. Possible differences in functional outcomes between the two modalities have not been profoundly studied. The objective of the study was to investigate the specificity of neuromuscular adaptations in response to two balance intervention modalities within test and intervention paradigms containing characteristics of both profiles: classical sensorimotor training (SMT) referring to a static ledger pivoting around the ankle joint vs. reactive balance training (RBT) using externally applied perturbations to deteriorate body equilibrium. Thirty-eight subjects were assigned to either SMT or RBT. Before and after four weeks of intervention training, postural sway and electromyographic activities of shank and thigh muscles were recorded and co-contraction indices (CCI) were calculated. We argue that specificity of training interventions could be transferred into corresponding test settings containing properties of SMT and RBT, respectively. The results revealed that i) postural sway was reduced in both intervention groups in all test paradigms; magnitude of changes and effect sizes differed dependent on the paradigm: when training and paradigm coincided most, effects were augmented (P<0.05). ii) These specificities were accompanied by segmental modulations in the amount of CCI, with a greater reduction within the CCI of thigh muscles after RBT compared to the shank muscles after SMT (P<0.05). The results clearly indicate the relationship between test and intervention specificity in balance performance. Hence, specific training modalities of postural control cause multi-segmental and context-specific adaptations, depending upon the characteristics of the trained postural strategy. In relation to fall prevention, perturbation training could serve as an extension to SMT to include the proximal segment, and thus the control of structures near to the body’s centre of mass, into training.

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

“…As a consequence, RBT requires an accurate repositioning of the center of mass (COM) utilizing rapid and appropriate neuromuscular responses to regain a stable body position after surface translation. Thus, RBT may challenge reactive postural stability more than CBT ( Horstmann and Dietz, 1990 ; Yim-Chiplis and Talbot, 2000 ) and may be more effective as an intervention to counteract falls ( Freyler et al, 2016 ).…”

A trip to remember

“…In studies on perturbation-based balance training (PBT), specific improvements in dynamic and perturbed balance tasks are observed, as expected, but no or minimal changes are seen in less dynamic or static balance tasks (Freyler et al, 2016, Chien and Hsu, 2018, Krause et al, 2018, although one study has reported beneficial transfer effects from PBT to standing balance (Kurz et al, 2016). Accordingly, it is not surprising that PBT leads to better performance of rapid balance control tasks than traditional proactive balance control training (Freyler et al, 2016) and Tai-Chi training (Aviles et al, 2019). As discussed in Chapter 5.1, PBT for falls prevention concords more to the principles of specificity in training and learning than does traditional balance training, so these results should not be surprising, and I recently attempted to recapitulate this: "We do not expect athletes to win Olympic medals without practising the skills of their sports, so why should we expect older adults to fall less often without practising the skills required for avoiding falls?"…”

“…One systematic review has demonstrated a task-specific effect of balance training in healthy adults and children, whereby trained tasks improve with practice, but untrained tasks do not generally improve (Kummel et al, 2016). In studies on perturbation-based balance training (PBT), specific improvements in dynamic and perturbed balance tasks are observed, as expected, but no or minimal changes are seen in less dynamic or static balance tasks (Freyler et al, 2016, Chien and Hsu, 2018, Krause et al, 2018, although one study has reported beneficial transfer effects from PBT to standing balance (Kurz et al, 2016). Accordingly, it is not surprising that PBT leads to better performance of rapid balance control tasks than traditional proactive balance control training (Freyler et al, 2016) and Tai-Chi training (Aviles et al, 2019).…”

Perturbation-Based Balance Training in Postoperative Individuals With Degenerative Cervical Myelopathy

“…Third, lack of a comparison group receiving only treadmill training may raise concerns on whether the effects of the training were attributable to both PBT and treadmill training (Steib et al, 2017;Handelzalts et al, 2019). However, the more pronounced neuromuscular modulation effects with the addition of perturbation to balance training compared with conventional balance training were reported previously (Freyler et al, 2016;Krause et al, 2018). In addition, the effectiveness of PBT may be challenged without the follow-up assessment for the control group.…”