Comparison of resistance training progression models on maximal strength in sub-elite adolescent rugby union players

To determine changes in maximal strength between two different resistance training progression models, linear (LP) and daily undulating (DUP), over a 12-week resistance training programme in sub-elite adolescent rugby union players.

The study used a quasi-experimental study design. Following baseline assessments, participants from Squad 1 were randomised to either LP or DUP; participants from Squad 2 formed a non-randomised comparison group (CON).

Participants were 26 sub-elite adolescent rugby union players who were assessed at baseline and after 12 weeks. Outcomes included 5 repetition maximum (RM) box squat and bench press, height, body weight, skeletal muscle mass, percentage body fat and maturation status.

Participants in both the LP and DUP groups significantly increased their squat and bench press strength from baseline to 12 weeks. There were no significant differences between groups for squat and bench press increases after 12 weeks (p>0.05). No significant increases in squat or bench press strength were observed after 12 weeks in the CON group. Increases in lower body strength were large in the LP group (ES: 1.64) and very large in the DUP group (ES: 2.33). Upper body strength changes were small in both groups (LP, ES: 0.57; DUP, ES: 0.31).

Twelve weeks of LP or DUP resistance training are both effective at increasing maximal lower and upper body strength in adolescent rugby athletes. Additionally, twice weekly frequency of resistance training in adolescent rugby athletes with greater than 6-months resistance training experience is sufficient to elicit substantial increases in maximal strength.