Table 2.

The exercise programs of the interventions

	Flywheel group	Barbell Free Weight group	Control Group
Equipment	Flywheel Device	Olympic Barbell, free weight and squat rack.	N/A
Exercise sets and repetitions (intensity)
Week 1 (Familiarization sessions)
Intervention exercise	3 × 6 (inertia #1, #2, #3 or #4)	3 × 8 (~ 70% of 1RM)	N/A
Nordic Hamstring	3 × 4 (Body weight)	3 × 4 (Body weight)	N/A
Week 2
Criteria for increasing load	An average > 4 watts·kg−1 from each repetition of one set	If they could perform five repetitions within one set	N/A
Intervention exercise	3 × 6 (inertia #1, #2, #3 or #4)	4 × 4 (> 85% of 1RM)	N/A
Nordic Hamstring	3 × 5	3 × 5 (Body weight)	N/A
Week 3
Intervention exercise	3 × 5 (inertia #1, #2, #3 or #4)	4 × 4 (> 85% of 1RM)	N/A
Nordic Hamstring	3 × 6 (Body weight)	3 × 6 (Body weight)	N/A
Week 4
Intervention exercise	4 × 5 (inertia #1, #2, #3 or #4)	4 × 4 (> 85% of 1RM)	N/A
Nordic Hamstring	3 × 6 (Body weight)	3 × 6 (Body weight)	N/A
Week 5
Intervention exercise	4 × 4 (inertia #1, #2, #3 or #4)	4 × 4 (> 85% of 1RM)	N/A
Nordic Hamstring	3 × 8 (Body weight)	3 × 8 (Body weight)	N/A
Week 6
Intervention exercise	4 × 4 (inertia #1, #2, #3 or #4)	4 × 4 (> 85% of 1RM)	N/A
Nordic Hamstring	3 × 10 (Body weight)	3 × 10 (Body weight)	N/A

N/A Not applicable. Inertia #1 = 0.025 kg·m⁻², #2 = 0.05 kg·m^− 2, #3 = 0.075 kg·m^− 2 or #4 = 0.1 kg·m^− 2