Strength training in soccer with a specific focus on highly trained players

Abstract

Background: Data concerning the physical demands of soccer (e.g., activity pattern) suggest that a high level of performance requires well-developed neuromuscular function (NF). Proficient NF may be relevant to maintain and/or increase players' short- (intense periods of soccer-specific activity; accelerations, decelerations, and sprinting) and long-term performance during a match and throughout the season.

Objective: This review examines the extent to which distinct modes of strength training improve soccer players' performance, as well as the effects of concurrent strength and endurance training on the physical capacity of players.

Data sources: A selection of studies was performed in two screening phases. The first phase consisted of identifying articles through a systematic search using relevant databases, including the US National Library of Medicine (PubMed), MEDLINE, and SportDiscus. Several permutations of keywords were utilized (e.g., soccer; strength; power; muscle function), along with the additional scanning of the reference lists of relevant manuscripts. Given the wide range of this review, additional researchers were included. The second phase involved applying six selection criteria to the articles.

Results and conclusions: After the two selection phases, 24 manuscripts involving a total sample of 523 soccer players were considered. Our analysis suggests that professional players need to significantly increase their strength to obtain slight improvements in certain running-based actions (sprint and change of direction speed). Strength training induces greater performance improvements in jump actions than in running-based activities, and these achievements varied according to the motor task [e.g., greater improvements in acceleration (10 m) than in maximal speed (40 m) running movements and in non-squat jump (SJ) than in SSC-based actions (countermovement jump)]. With regard to the strength/power training methods used by soccer players, high-intensity resistance training seems to be more efficient than moderate-intensity resistance training (hypertrophic). From a training frequency perspective, two weekly sessions of strength training are sufficient to increase a player's force production and muscle power-based actions during pre-season, with one weekly session being adequate to avoid in-season detraining. Nevertheless, to further improve performance during the competitive period, training should incorporate a higher volume of soccer-specific power-based actions that target the neuromuscular system. Combined strength/power training programs involving different movement patterns and an increased focus on soccer-specific power-based actions are preferred over traditional resistance exercises, not only due to their superior efficiency but also due to their ecological value. Strength/power training programs should incorporate a significant number of exercises targeting the efficiency of stretch-shortening-cycle activities and soccer-specific strength-based actions. Manipulation of training surfaces could constitute an important training strategy (e.g., when players are returning from an injury). In addition, given the conditional concurrent nature of the sport, concurrent high-intensity strength and high-intensity endurance training modes (HIT) may enhance a player's overall performance capacity. Our analysis suggests that neuromuscular training improves both physiological and physical measures associated with the high-level performance of soccer players.

Figure 1

The gains in strength and d ifferent motor abilities of high-level players after 5 to 10 weeks. Squares represent the average squat jump performance [1,6,14,22]; rhombi represent the average countermovement jump performance [2,22,37]; triangles represent the average four bounce test performance [6]; circles represent the average 10-m sprint performance [2,22,37,38]; x symbols represent the average 40-m sprint performance [1,2,6]; + symbols represent the average change in direction ability [2,38]; and lines represent the average of all the previous motor tasks.

Figure 2

Gains in strength and motor abilities of high level players after different training modes (5 to 10 weeks). x and dashed x symbols represent the change of direction ability performance after traditional resistance exercises programs (TRE) [2] and combined programs (COM) [38], respectively; filled and unfilled squares represent the 40-m sprint performance after TRE [1,2] and COM [6], respectively; + and dashed + symbols represent the 10-m sprint performance after TRE [2,37] and COM [22,38], respectively; filled and unfilled triangles represent the four bounce test performance after TRE [6] and COM [6], respectively; filled and unfilled rhombi represent the squat jump performance after TRE [1,14] and COM [6,22], respectively; and filled and unfilled circles represent the countermovement jump performance after TRE [2,37] and COM [22], respectively.

Figure 3

Percentage of improvement by training program and training session. Percentage of improvement by training program and training session after traditional resistance exercises programs (TRE), combined programs (COM), and strength/power training programs in the different motor tasks and overall functional performance (FP) of high-level players. Countermovement jump (CMJ) after TRE (CMJ-TRE) [2,20,37]; CMJ after COM (CMJ-COM) [22,23,38]; CMJ [2,20-23,37,38]; squat jump (SJ) after TRE (SJ-TRE) [1,14]; SJ after COM (SJ-COM) [6,19,22]; SJ [1,6,14,19,22]; 40-m sprint performance after TRE (40m-TRE) [1,2]; 40-m sprint performance after COM (40m-COM) [6]; 40-m sprint performance (40-m) [1,2,6]; 10-m sprint performance after TRE (10m-TRE) [2,20,37]; 10-m sprint performance after COM (10m-COM) [22,38]; 10-m sprint performance (10m) [2,20-22,37,38]; change of direction ability (COD) after TRE (COD-TRE) [2]; COD after COM (COD-COM) [38]; COD [2,38]; FP after TRE (FP-TRE) [1,2,6,14,20,37]; FP after COM (FP-COM) [6,19,22,23,38]; and FP [1,2,6,14,19-23,37,38].