Understanding and Treating Balance Impairment in Multiple Sclerosis

In a recent RCT to evaluate the comparative effectiveness of different methods of resistance training, Hayes et al [123] determined that the addition of high-intensity, eccentric resistance training offered no additional benefit over standard concentric resistance exercise in improving static standing balance and stair climbing. In addition, compared with no exercise or a home-based program to improve strength and balance, progressive resistance cycling showed significantly greater effect on functional reach and timed up-and-go in individuals with moderate MS [128]. Nonetheless, evidence for the efficacy of home-based training remains equivocal given issues of motivation, adherence, and training intensity [115,118,128].

Taken together, the systematic reviews to date conclude that there is insufficient evidence for the effects of resistance exercise on balance in MS, thus making solid evidenced-based conclusions difficult [108,110,113,129]. Moreover, it is difficult to ascertain a definitive and most efficacious exercise prescription for improving balance in MS given the inconsistency in protocols and findings across studies. There is some support, albeit preliminary, for progressive resistance training as a modality to improve balance, especially those functional tasks demanding greater strength [113]. Nonetheless, resistance training may contribute to improved posture and gait given it directly addresses one context of postural control, but it may not be fully effective due to lack of training to modify central neural control of posture in other contexts.

Aerobic Exercise

Many of the studies examining aerobic exercise in MS more often target walking capacity, exercise tolerance, fatigue, and quality of life than balance [130]. The limited research that has focused on aerobic exercise for balance improvement has shown equal benefit to that achieved from resistance exercise in those contexts involving limits of stability and dynamic balance while stepping or walking [119]. This finding was reasonable given that the aerobic exercise included step-up and treadmill walking. Still, it has been recommended that, for most people with MS, aerobic exercise also incorporate a degree of balance training [109].

Combined Exercise

The more recent exercise research involving people with MS often combines some aspect of aerobic, strengthening, and/or balance exercise. While only a few RCTs have examined the effects of combined training in this population, preliminary evidence suggests it is well tolerated and may have some benefit for improving function [110]. While one study found no differences in static balance after a combined strength and aerobic training program [131], review of the exercise protocol revealed that the training regime had only incorporated 2 standing exercises. Other studies more intentionally combining strength and balance exercise have demonstrated benefits in balance confidence [132], standing static balance or postural sway [132–134], step climbing [133], and functional mobility [135]. Combining aerobic exercise and strengthening has also been effective in reducing falls in those with MS [85].

Balance-Specific Exercise

Only one balance-specific RCT has been published to date. In this study, outcomes from balance training involving both motor and sensory strategies were compared to training of only motor strategies and to standard therapy [136]. Both the balance training groups significantly reduced the number of falls post intervention as compared to the conventional treatment group. There were no observed differences in self-reported balance confidence across the groups, although both the balance training groups significantly improved in static and dynamic standing balance over that achieved by the standard treatment group. The fact that only the group engaged in sensory training differed significantly on dynamic gait highlights the importance of sensory integration for dynamic balance and gait.