There is a growing body of evidence highlighting the positive effects of both plyometric and strength training for youth athletes. A little earlier this week, we posted that plyometric training in youth soccer players improves many physical performance indicators including, speed, strength & peak power. And a more recent study by Keiner et al. (2012) has demonstrated that when it comes to strength training, elite youth soccer players are trainable at any age in adolescence.
141 elite youth players were tested for 1 repetition maximum (1RM) of their front & back squat. The authors expressed the results in terms of players strength to mass ratio (SREL). The athletes were divided into four sub-groups per age, and subsequently into control groups by age in the following order: group A U19, group B U17, group C U15, and group D U13. These athletes trained concurrently in both soccer and strength training for two years, while the control group (CG) only trained in soccer during the same period. After two years, the players were retested for front and back squat with the following results:
Group A SREL for front squat: 1.50 / Group A SREL for back squat: 1.70
Group B SREL for front squat: 1.40 / Group B SREL for back squat: 1.60
Group C SREL for front squat: 1.20 / Group C SREL for back squat: 1.40
Group D SREL for front squat: 0.70 / Group D SREL for back squat: 0.90
Following two years, each group here demonstrated significantly greater strength than CG (p<0.001) when both 1RM and strength to mass ratio is measured i.e. strength training can benefit the physical profile of youth soccer players. To our knowledge, this is the first cross-sectional study that reports front & back squat strength ratios in elite youth players. While individual variations for team members is likely to be observed by coaches, it is interesting to note the trainability of soccer players in strength is evident throughout adolescence.