Table 1. Summary of training intervention and changes in professional rugby league strength and power studies.

Study	Competition	Participant characteristics	Performance measures	Length of intervention	Training stimulus	Performance effect %	ES
Pre-Season
O’Connor and Crowe, 200)	NRL	n = 8 24.9 2 1.5 yrs, 94.7 9 2.0 kg,	3 RM bench press 3 RM deadlift 3 RM DB shoulder press 3 RM prone row Chin ups 10 s leg power test	6 weeks	RT 3/wk (25-30 sets/session x 2-6 reps @ 80-95%) Speed/power 1/wk Con 4/week TP 4/wk	BP B 3.5 0.1 DL D 10.9 0.5 DB SP D 7.6 1.3 Row R 0.8 0.5 Chins C 3.4 1.7 W/kg / 6.8 1.0	0.71 1.55 1.25 0.20 0.30 0.86
Rogerson et al., 2007	NRL	n = 11 19.0 1 1.3 yrs, 87.6 8 9.0 kg, 1.81 1 0.05 m	2 RM bench press 2 RM leg press 2 RM deadlift 2 RM seated row	5 weeks	RT 4/wk LB (4 sets x 2-8 reps) Vol load: 15,394 8 2,085 kg UB (4 sets x 2-8 reps and 2 sets x 20 reps) Vol load: 6,715 8 569 kg Whole-body RT (4 sets x 1-4 reps) Vol load: 8,120 4 1,207 kg	BP B 10.9 3.6 LP L 25.1 5.6 DL D 17.4 3.2 SR S 10.2 5.8	0.78 1.15 0.84 0.69
Harris et al., 2008	NRL	n = 18 21.8 2 4.0 yrs, 96.2 9 9.9 kg, 1.81 1 0.05 m	1 RM hack-squat machine Loaded hack-squat machine squat jumps @ 20, 30, 40, 50, 60, 70 and 80% of 1 RM	7 weeks	Machine squat jumps 5 sets x 5 reps @ 80% 2/wk (except week 4 1/wk) UB 2/wk Sprints*	1 RM 1 16.6 3.2 1 RM/kg / 16.5 1.3 N N 8.8 9.9 N/kg / 9.9 8.8 W W 17.1 9.1 W/kg / 17.1 9.0	0.86 0.99 N/A N/A N/A N/A
				7 weeks	Machine squat jumps 6 sets x 10-12 reps @ individual PP output 2/wk (except week 4 1/wk) UB 2/wk Sprints*	1RM 1 9.2 0.9 1RM/kg / 8.3 1.2 N N 2.2 10.1 N/kg / 4.5 10.1 W W 6.0 18.3 W/kg / 6.5 16.6	0.47 0.40 N/A N/A N/A N/A
Comfort et al., 2012	Super league	n = 19 96.2 9 11.11 kg, 1.84 1 0.06 m,	1 RM back squat	8 weeks	RT and TP 2/wk Ag and Plyo1/wk Weeks 1 – 4 strength (4 sets x 4-6 reps @ 85-90%) Week 5 – 8 power (4 sets x 3-6 reps @ 85%)	1 RM 1 17.7 3.7 1 RM/kg / 15.2 5.8	1.04 0.84
de Lacey et al., 2014a	NRL	n = 9 24 2 3.6 yrs, 99.0 9 12.2 kg, 1.83 1 0.06 m	Jump squats @ 25, 50, 75 and 100% body mass	3 weeks	7 wks, IRV 358.4/wk (6-15 reps at 65-83%) 6 wks, IRV 6 to 156.87/wk (3-6 reps at 80-95%) 3 wks, IRV 3 to 40.8/wk Field sessions 60 mins 3-4/wk	W/kg / 28.2 23.4 JH25% J 20.6 14.9 JH50% J 32.9 22.7 JH75% J 43.2 29.8 JH100% J 42.9 50.3	0.82 0.88 1.05 0.99 0.89
Daniels et al., 2019	Super league	n = 22 23.3 2 4.4 yrs, 91.6 9 8.9 kg, 1.81 1 0.07 m	3 RM back squat Prone pull ups 1 RM bench press Bench throw Jump squat	7 weeks	RT 4/wk Wrestle 2/wk TP 4/wk Con 1/wk	3 RM 3 9.9 1.1 Pull ups P 53.3 2.5 1 RM 1 4.0 0.3 BT PP B 6.0 0.6 SJ PP S 3.0 0.2	0.63 0.89 0.26 0.36 0.45
Competition
Baker, 2001b	NRL	n = 14 24.5 2 3.5 yrs, 93.7 9 10.1 kg, 1.82 1 0.07 m	1 RM bench press Bench throw @ 40, 50, 60, 70 and 80 kg Jump squats @ 40, 60, 80 and 100 kg	29 weeks	RT 2 whole-body/wk 1st session strength maintenance 2nd session power maintenance Con 2-3 x 20-30 min/wk TP 3-5 x 60 min/wk 1 match/wk	1 RM 1 1.2 1.1 BT Pmax B 0.3 5.6 JS Pmax J 1.2 0.3	-0.11 -0.02 -0.07
Crewther et al., 2011	Super league	n = 12 23.4 2 3.6 yrs, 95.4 9 11.0 kg, 1.83 1 0.55 m	Countermovement jump height Isometric mid-thigh pull	6 weeks	6 days/wk 12 sessions/wk RT, Con, TP, recovery x 45-90 min/session 1-2 matches/wk	CMJ JH C 4.17 1.59 IMTP PF I 1.07 0.93	0.3 -0.1
Longitudinal
Baker and Newton, 2006	NRL	n = 12 21.3 2 1.4 yrs, 95.5 9 10.4 kg, 1.86 1 0.05 m	1 RM bench press Bench throw @ 40, 50, 60, 70 and 80 kg	4 years	General preparation UB RT 2/wk LB RT 2/wk Con 5/wk Specific preparation UB RT 2/wk LB RT 2/wk Con 2-3/wk Competition RT 2 whole-body/wk 1st session strength maintenance 2nd session power maintenance Con 2-3 x 20-30 min/wk TP 3-5 x 60 min/wk	1 RM 1 6.0 0.5 Pmax P 5.0 2.7	0.55 0.39
Baker and Newton, 2008a	NRL	n = 6 19.3 1 1.0 yrs, 95.8 9 9.8 kg, 1.85 1 0.05 m	1 RM back squat Jump squats @ 40, 60, 80 and 100 kg	4 years		1RM 1 14.1 0.3 Pmax P 13.3 6.2 P40 P 15.3 8.9 P60 P 15.2 8.9 P80 P 12.1 3.9 P100 P 5.3 11.6	0.65 0.64 0.73 0.78 0.54 0.25
Baker and Newton, 2008b	NRL	n = 11 20.3 2 1.7 yrs, 97.8 9 9.7 kg, 1.87 1 0.05 m	1 RM bench press Bench throw @ 40, 50, 60, 70 and 80 kg	6 years		1 RM 1 11.1 0.6 Pmax P 14.9 3.2	0.68 0.70
Baker, 2013	NRL	n = 6 19.3 1 1.6 yrs, 95.8 9 14.6 kg, 1.86 1 0.07 m	1 RM bench press Bench throw @ 40, 50, 60, 70 and 80 kg	10 years		1 RM 1 22.3 13.0 Pmax P 23.1 0.9	1.09 1.17

*denotes limited information presented in study, NRL; national rugby league, RM; maximal strength, RT; resistance training, Con; aerobic conditioning, TP; team practice, BP; bench press, DL; deadlift, DB SP; dumbbell shoulder press, PP; peak power, LB; lower body, UB; upper body, LP; leg press, SR; seated row, RM/kg; relative maximal strength, /; increase, ;; decrease, W; peak power, W/kg; relative peak power, N; peak force, N/kg; relative peak force, Ag; agility training, Plyo; plyometric training, IRV; mean intensity relative volume, Pmax; maximal power, JH; jump height, BT; bench throw, SJ; jump squat, CMJ; counter movement jump, JH; jump high, IMTP; isometric mid-thigh pull, PF; peak force, P40; power output at 40 kg, P60; power output at 60 kg, P80; power output at 80 kg, P100; power output at 100 kg.