Three months of slackline training elicit only task-specific improvements in balance performance

Abstract

Slackline training is a challenging and motivating type of balance training, with potential usefulness for fall prevention and balance rehabilitation. However, short-term slackline training seems to elicit mostly task-specific performance improvements, reducing its potential for general fall prevention programs. It was tested whether a longer duration slackline training (three months, 2 sessions per week) would induce a transfer to untrained tasks. Balance performance was tested pre and post slackline training on the slackline used during the training, on a slackline with different slack, and in 5 different non-trained static and dynamic balance tasks (N training = 12, N control = 14). After the training, the training group increased their performance more than the control group in both of the slackline tasks, i.e. walking on the slackline (time × group interaction with p < 0.001 for both tasks). However, no differences between groups were found for the 5 non-trained balance tasks, only a main effect of time for four of them. The long-term slackline training elicited large task-specific performance improvements but no transfer to other non-trained balance tasks. The extensive slackline training that clearly enhanced slackline performance did not improve the capability to keep balance in other tasks and thus cannot be recommended as a general fall prevention program. The significant test-retest effect seen in most of the tested tasks emphasizes the need of a control group to adequately interpret changes in performance following balance training.

Six weeks of balance or power training induce no generalizable improvements in balance performance in healthy young adults

“…In addition to the lacking effect on the learning rate during the acquisition of a novel task, no direct transfer to the untrained tasks was observed when comparing the first ten trials after the training between groups. This result is in line with previous training studies that were designed to assess the effect of balance training on untrained balance tasks, and found large effects only in the tasks that had been trained [7–10, 12, 14], underpinning the task-specificity principle of balance training. The task-specificity effect observed here can be explained by the task-specific neural adaptations following balance training [26].…”

“…This effect can be explained, at least partly, by the experimental test-retest paradigm [27]. This effect emphasizes the need for a control group in studies testing the effect of different types of balance training on balance performance [12].…”

“…This rather limited impact could be partly due to the fact that, like for most skill training, “learning tends to be quite specific to the trained regimen and does not transfer to even qualitatively similar tasks” [6]. Indeed, in several recent studies and reviews, the quick and large improvement of performance induced by balance training has been shown to be mostly specific to the task trained [7–11], even after months of training [12]. This means that after having trained one balance task (for example, keeping a one-leg stance on one unstable surface such as a slackline), trainees will improve their performance in this task, but will not perform better than control participants in untrained balance tasks (for example, keeping a one-leg stance on a different unstable surface such as a tilt board).…”

Motor learning induces time‐dependent plasticity that is observable at the spinal cord level

“…Whatever the mechanisms might be behind the observed task-specific modulation of the H-reflex, these changes might be important because they can determine early consolidation mechanisms (Muellbacher et al 2002), as well as interference and reconsolidations effects (Walker et al 2003). This short-term task specific adaptation may also explain the previously observed task-specific change in balance performance and the lack of performance transfer to an untrained balance task (Giboin et al 2015(Giboin et al , 2018Giboin et al 2019a, b) that was accompanied by task-specific H-reflex modulation after 6 weeks of training (Giboin et al 2019c). It should be noted that the present results do not preclude the existence of long-term general spinal adaptations, such as that observed in ballet dancers or power-trained athletes (Casabona et al 1990;Nielsen et al 1993).…”

Do Grade II Ankle Sprains Have Chronic Effects on the Functional Ability of Ballet Dancers Performing Single-Leg Flat-Foot Stance? An Observational Cross-Sectional Study

“…As ankle control is crucial for successfully executing ballet specific positions and it could be impaired in ankle sprains, a position specific testing with closed eyes is needed. Moreover, some studies showed that athletic and sport training is task specific and skills acquired in a specific task did not completely translate to the same skills in different tasks [29][30][31]. Recently, Thalassinos et al discovered that there were many sport skill-specific bias about sensory inputs for spatial orientation and postural control between experienced soccer athletes, ballet dancers, and nonathletes [32].…”