Effects of MTM1 mutation on walking gait in dogs. XLMTM (red) and their control littermates (black) walked repeatedly over an instrumented carpet to capture spatiotemporal measures of gait including (A) gait speed, (B) stride length, (C) stance time, (D) stride time, (E) stance percentage, (F) swing time. XLMTM, X-linked myotubular myopathy.