運動中のけいれんをシミュレートするための電気誘発けいれんの適用

抄録

In this study, the application of electrical stimulation known to cause muscle cramps to simulate a gastrocnemius cramp during stair climbing was investigated. If gastrocnemius cramps can be consistently and repeatedly generated in this condition, an environment to simulate cramping while wearing a lower limb exoskeleton during a dangerous motion assist condition is possible. This type of environment can be used to develop exoskeleton control responses to involuntary muscle activity from cramp. To the author’s knowledge, there have been no studies done that have attempted to electrically elicit a medial gastrocnemius muscle cramp in any position other than lying prone. This study is the first attempt to apply electrical cramp induction to the gastrocnemius in multiple positions and motions that occur in stair climbing. These experimental conditions were used to confirm if cramp generation is still possible, consistent, and what the limitations of electrically elicited cramp are in this application. We find that electrical stimulation is ineffective to produce a gastrocnemius cramp during stair climb due to a limited time window to produce the cramp, a stimulation duration of multiple seconds needed to form a cramp, and a noticeable increase in resistance to cramp production from electrical induction while standing. However, this method could still be viable if additional conditions known to lead to a cramp prone state are additionally applied, or the subjects are all naturally susceptible to cramping.