Modifying the pre-pitch entry practices of professional soccer substitutes may contribute towards improved movement-related performance indicators on match-day: A case study

Abstract

Modifying a soccer substitute's pre-pitch-entry activities may represent an opportunity to maximise physical performance and minimise injury-risk following match-introduction. Using a professional team that has previously participated in substitute profiling research, this follow-up case study investigated the effects of a modified match-day protocol that included substitutes; 1) performing a new pre-match warm-up alongside members of the starting team (as opposed to a separate substitute-only warm-up), 2) participating in a staffled half-time rewarm-up (as opposed to player-led half-time activities), and 3) receiving ongoing education focusing on the efficacy of (re)warm-up activities. English Championship substitutes (n = 15) were monitored using Micro-electromechanical Systems during 13 matches incorporating the modified practices (35 observations). On an individual player basis, data were organised into bouts of warm-up activity (pre-pitch-entry) and five min epochs of match-play (post-pitch-entry). Linear mixed modelling assessed the influence of 'bout' and 'epoch', position, and scoreline. Substitutes performed 3±1 rewarm-up bouts�player-1 �match-1 between kick-off and pitch-entry, which were shorter (-17.2 to-27.1 min) and elicited less distance (-696 to-1257 m) than the pre-match warm-up (p�0.001). Compared with previous data, heightened absolute movement responses were observed during the pre-match and staff-led half-time (re)warm-ups, alongside greater relative distances covered during player-led activities performed between kick-off and pitch-entry. Whilst less distance (-10%) was covered during the second versus first five min period following matchintroduction, values remained higher than previously reported. Between pitch-entry and the end of the match, the scoreline improved and worsened following 26% and 11% of substitutions, respectively; a favourable record compared with existing observations. Acknowledging the likely contribution from external factors, this case study reports heightened movement profiles and improved match scorelines when pre-pitch-entry practices were modified. Practitioners should note the potential influence of match-day activities on the

Profiling the Post-match Top-up Conditioning Practices of Professional Soccer Substitutes: An Analysis of Contextual Influences

“…Whereas absolute HSR in the current study equated to <50% of whole-match values for players occupying outfield players (9, 14, 31), relative HSR of ~28.1 m•min -1 far exceeds the ~4.8-10.1 m•min -1 typically recorded across a playing bout for both partial-and whole-match players (7,9,19). Indeed, such values broadly reflect the relative HSR responses reported during the 'peak' 2-3 min period of match-play (13,17,20).…”

“…Given the role of top-ups as a means of offsetting discrepancies in match-play demands, it is unsurprising that unused members of the match-day squad recorded generally greater absolute top-up responses compared with players who had experienced partial match-play (i.e., those substitutes who were deployed during the immediately preceding match). However, acknowledging that any match-exposure must also be considered when assessing an individual's overall match-day loading, and that considerable variation may exist in relation to a substitute's match demands, an existing study of English Championship soccer players indicated that substitutes typically covered just ~0.1 km of HSR following entry onto the pitch (19).…”

“…Moreover, substitutes may accumulate little or no HSR or SPR during preparatory activities performed prior to match introduction (18,19), with many practitioners deeming a substitute's pre-pitch-entry responses to be too minimal to warrant inclusion within assessments of match-day loading (22). As match-play may represent an important stimulus for promoting sport-specific physical adaptations (29,35), the likely reduction in absolute match-day loading for unused or partial-match players compared with their whole-match counterparts has the potential to negatively influence an individual's adaptive responses, particularly for those who are repeatedly omitted from the starting team over the course of multiple fixtures.…”

“…Session duration, as well as a combination of Global Positioning Systems-and accelerometer-derived variables relating to TD, low-speed running distance (LSR), moderate-speed running distance (MSR), HSR, SPR, PlayerLoad™ (PL), maximum velocity achieved, repeated highintensity efforts (RHIEs), accelerations, and decelerations, were profiled (Table 1). These variables were chosen to reflect performance indicators reported in existing substitutes literature (18,19). In keeping with the observational nature of the study, no attempt was made to influence players' responses as part of this research.…”

“…In professional soccer, team managers or coaching staff often use substitutions to provide a physical or tactical impact upon a match, and thus potentially improve scoreline differentials (22). Strategic substitutions (i.e., replacements that are not made due to injuries sustained by on-pitch players) are most often made at half-time or during the second-half of match-play (7,18,19,21), with individuals entering the pitch typically exceeding the relative total (TD) and/or high-speed running (HSR) distances of players who started a match (7,21). However, substitutes consistently experience substantially lower absolute match-play demands compared with players who complete the full 90 min (19), whilst their reduced playing time may also restrict a substitute's opportunity to attain the 'peak' HSR responses of their whole-match counterparts (20).…”