ICG time series along PIPA (Plantar-impulse length is rated by percentage).

p<0.05, showing the significant difference between the ICGs from the elderly subjects’ free gait and those from the young subjects’ free, fast and slow gait; p<0.05, showing the significant difference between the ICGs from the young subjects’ fast gait and those from the young subjects’ free, slow gait and the elderly subjects’ free gait; p<0.05, showing the significant difference between the ICGs from the young subjects’ slow gait and those from the young subjects’ free, fast gait and the elderly subjects’ free gait. T-TEST uses the two-tailed distribution, two-sample unequal variance (heteroscedastic).