Stride time in 15 different walking conditions.
From left to right, the walking conditions are uphill 15%_sub-threshold, uphill 15%_no, uphill 15%_supra-threshold, uphill 8%_sub-threshold, uphill 8%_no, uphill 8%_supra-threshold, level_sub-threshold, level_no, level_supra-threshold, downhill 8%_sub-threshold, downhill 8%_no, downhill 8%_supra-threshold, downhill 8%_sub-threshold, downhill 8%_no, downhill 8%_supra-threshold, respectively. Error bars indicate between-participant standard deviations. X indicates the mean of stride time. The symbols *, #, and & indicate the significant difference among inclines; ! and $ indicate the significant difference among vibration conditions.