Intensity and generalization of treadmill slip training: High or low, progressive increase or decrease?

Abstract

Very little is known how training intensity interacts with the generalization from treadmill-slip to overground slip. The purposes of this study were to determine whether treadmill-slip training improved center-of-mass stability, more so in the reactive than in the proactive control of stability, with high intensity (HI with a trial-to-trial-consistent acceleration of 12 m/s2) better than low intensity training (LO with a consistent acceleration of 6 m/s2), and progressively-increasing intensity (INCR with a block-to-block acceleration varied from 6 to 12 m/s2) better than progressively-decreasing intensity training (DECR with an acceleration varied from 12 to 6 m/s2) in such generalization. Thirty-six young subjects evenly assigned to one of four (HI, LO, INCR, DECR) groups underwent 24 treadmill-slips before their generalization test trial with a novel slip during overground walking. The controls (CTRL, n=9) from existing data only experienced the same novel overground slip without treadmill training but under otherwise identical condition. The results showed that treadmill-slip training did improved balance control on overground slip with a greater impact on subjects’ reactive (44.3%) than proactive control of stability (27.1%) in comparison to the CTRL. HI yielded stronger generalization than LO, while INCR was only marginally better than DECR. Finally, the group means of these four displayed a clear ascending order from CTRL, LO, DECR, INCR, to HI. The results suggested that higher training intensity on treadmill led to a better generalization, while a progressively-increase in intensity had advantage over the progressively-decrease or the low training strategy. (243 words)

Generalization of treadmill perturbation to overground slip during gait: Effect of different perturbation distances on slip recovery

“…Consequently, it yielded significantly better proactive (−0.11 ± 0.05, p <0.05) and reactive (−0.12 ± 0.09, p <0.05) control of stability than the outcomes in the present study. Another TM-training study employed 6 m/s 2 and 12 m/s 2 (Liu et al, in press), where a higher intensity did yield greater proactive and reactive control of stability during the same generalization test. The difference from 12 cm to 18 cm resulting from a change in accelearation from 6 m/s 2 to 9 m/s 2 in the present study was apparently insufficient to yield any meaningful difference for the generalization, and thus failed to support our Hypothesis Two.…”

Perturbation‐based balance training for falls reduction among older adults: Current evidence and implications for clinical practice

“…In young adults, exposure to smaller‐magnitude perturbations can improve stability control after larger‐magnitude perturbations 49. However, it has also been shown that younger adults can recover more effectively from an overground slip after high‐, rather than low‐, magnitude perturbation experience 50. Given the mixed evidence in young adults, and the benefits of both approaches shown in older adults, selecting perturbation magnitudes that are safe and tolerable while still challenging for the participant appears to be a reasonable choice for clinical applications.…”

Single and multiple step balance recovery responses can be different at first step lift-off following lateral waist-pull perturbations in older adults

“…Overall, the findings indicated that although reduced stability at first foot contact could be a determinant of taking additional steps, stepping responses could also be attributable to the COM motion state as early as first step lift-off, preceding foot contact. Since perturbation training has been reported to improve the reactive control of balance stability (Barrett et al, 2012; Dijkstra et al, 2015; Kurz et al, 2016; Mansfield et al, 2015; Pai et al, 2014; Rosenblatt et al, 2013), which increased balance stability at the instant of step lift-off (Lee et al, 2016; Liu et al, 2016), perturbation-based training interventions aimed at improving the reactive control of stability would reduce initial balance instability at first step lift-off and possibly the consequent need for multiple steps in response to balance perturbations.…”