Table 1. Information on participants for HSI‡ group. Participant Age (years) Hight (cm) Weight (kg) Injured limb Time since injury * (months) Total number of HSI † Activity at time of injury 1 24 163 61 non-dominant leg 4 3 Sprinting 2 29 177 73 non-dominant leg 6 2 Sprinting 3 24 176 61 dominant leg 23 2 Sprinting 4 18 172 64 non-dominant leg 23 1 Sprinting 5 19 176 62 dominant leg 36 1 Sprinting 6 18 176 67 non-dominant leg 35 2 Sprinting 7 23 172 68 non-dominant leg 6 2 Sprinting 8 23 169 68 dominant leg 3 1 Sprinting 9 23 175 68 dominant leg 6 3 Sprinting 10 29 172 70 dominant leg 6 1 Sprinting 11 29 172 68 dominant leg 9 3 Sprinting 12 22 183 73 dominant leg 6 2 Sprinting 13 27 169 65 dominant leg 26 3 Sprinting Time since injury *: The length of time since the most recent return to HSI. Total number of HSI †: Number of previous HSI and abbreviations (HSI) indicate hamstring strain injury. HSI‡: Hamstring strain injury.