Participants in this study will be individuals with chronic (> 6 months) hemiparesis following stroke or individuals with sub-acute stroke (> 6weeks and < 6 months), ambulatory (with or without assistive device) and more than 21 years of age. Subjects will be screened for the inclusion criteria. If subjects pass the screening, they will go through the full clinical balance assessment and laboratory dynamic stability test. The chronic stroke survivors will be randomized into two groups: - Group A: Slip training group; Group B: Control group. While, the sub-acute stroke survivors will be randomized into two groups: - Group C: Slip training group; Group D: Control group.