Monitoring Training and Match Physical Load in Junior Soccer Players: Starters versus Substitutes

Abstract

The aim of this study was to investigate differences in the physical (locomotor activities) and physiological (Banister’s training impulse) in-season training load between starters and substitutes in a well-trained junior soccer team. Physical performance variables from the Polar Team Pro system were collected and analyzed from a sample of junior soccer players (N = 18; age = 15.7 ± 0.5 years; stature, 177.9 ± 4.6 cm; body mass, 67.1 ± 5.5 kg). The study analyzed a total of 10 matches and 38 training sessions during the 2018 season with linear mixed models. The players from the starting line-ups demonstrated significantly higher average weekly physical load compared to the non-starters with respect to all variables: distance (total, running, high-speed running, and sprint) [F (1, 573) ≥ 66, p < 0.001, eta = 0.10], number of accelerations and sprints [F (1, 573) ≥ 66, p < 0.001, eta = 0.10], as well as Banister’s training impulse (TRIMP) [F (1, 569) = 10, p < 0.001, eta = 0.02]. Evidence from this study indicates that a large amount of weekly accumulated high-speed running and sprint distances is related to match playing time. Therefore, weekly fitness-related adaptations in running at high speeds seem to favor the starters in a soccer team.

Intra-Season Variations in Workload Parameters in Europe’s Elite Young Soccer Players: A Comparative Pilot Study between Starters and Non-Starters

“…Regarding training duration for the entire-squad, it was higher than the values reported by some authors in elite professional teams [1,22] and in elite U17-19 soccer players [9,21], however, it is similar to the values reported by Brink et al [37] in elite U19 soccer players. Moreover, as reported by Coutinho et al [38], the lower training frequencies in the youngest groups were balanced by a higher training stimulus.…”

“…This can be to the detriment of the team when it needs non-starter players. Through the fullseason, starters and non-starters could reveal different physiological adaptations [21], and recently, new evidence about workload and the player status has been shown in the scientific literature [12,22,23].…”

“…This is a very important aspect in soccer, highlighting the discrepancies in physical loads, which could impair the use of non-players in official matches [22]. Therefore, it is essential to monitor the weekly workload, in order to understand the impact on physical and psychological well-being and the differences in the workload between starters and non-starters [21,22], which could influence the performance in training and matches.…”

In-Season Internal and External Workload Variations between Starters and Non-Starters—A Case Study of a Top Elite European Soccer Team

“…For example, similar comparisons between starters and non-starters regarding the workload measures of new body load and metabolic power were found [ 11 ]. In junior soccer players, it was also found that weekly internal and external load measures were also significantly greater in starters than in substitute players [ 12 ].…”

Assessing the Perceived Exertion in Elite Soccer Players during Official Matches According to Situational Factors

“…Similarly, non-starter players declared a lower overall PE (6.7 ± 2.0) than young Spanish professional senior soccer players (respiratory PE = 4.6 ± 1.5; muscular PE = 4.1 ± 1.6) [13]. This finding could be explained by the greater high-speed running and sprinting distance imposed on starter players in comparison to non-starter ones in junior soccer players [24]. Therefore, the coaches of elite junior teams should consider that the game is harder for their players than for senior professional players when planning the training strategies of the previous and subsequent weeks.…”