The aim of this study was to examine the effect of playing formation on high-intensity running and technical performance during elite soccer matches. Twenty English FA Premier League games were analysed using a multiple-camera computerized tracking system (n = 153 players). Overall ball possession did not differ (P < 0.05) between 4-4-2, 4-3-3 and 4-5-1 formations (50%, s = 7 vs. 49%, s = 8 vs. 44%, s = 6). No differences were observed in high-intensity running between 4-4-2, 4-3-3 and 4-5-1 formations. Compared with 4-4-2 and 4-3-3 formations, players in a 4-5-1 formation performed less very high-intensity running when their team was in possession (312 m, s = 196 vs. 433 m, s = 261 vs. 410 m, s = 270; P 5 0.05) but more when their team was not in possession (547 m, s = 217 vs. 461 m, s = 156 vs. 459 m, s = 169; P < 0.05). Attackers in a 4-3-3 performed ~30% more (P < 0.05) high-intensity running than attackers in 4-4-2 and 4-5-1 formations. However, the fraction of successful passes was highest in a 4-4-2 (P < 0.05) compared with 4-3-3 and 4-5-1 formations. The results suggest that playing formation does not influence the overall activity profiles of players, except for attackers, but impacts on very high-intensity running activity with and without ball possession and some technical elements of performance.

The survey revealed the most common perceptions and practices of premier league football clubs internationally regarding risk factors, testing and preventative exercises. The findings can enable reduction of the gap between research and practice.

PurposeTo systematically review the scientific level of evidence for the ‘Top 3’ risk factors, screening tests and preventative exercises identified by a previously published survey of 44 premier league football (soccer) teams. Also, to provide an overall scientific level of evidence and graded recommendation based on the current research literature.MethodsA systematic literature search (Pubmed [MEDLINE], SportDiscus, PEDRO and Cochrane databases). The quality of the articles was assessed and a level of evidence (1++ to 4) was assigned. Level 1++ corresponded to the highest level of evidence available and 4, the lowest. A graded recommendation (A: strong, B: moderate, C: weak, D: insufficient evidence to assign a specific recommendation) for use in the practical setting was given.ResultsFourteen studies were analysed. The overall level of evidence for the risk factors previous injury, fatigue and muscle imbalance were 2++, 4 and ‘inconclusive’, respectively. The graded recommendation for functional movement screen, psychological questionnaire and isokinetic muscle testing were all ‘D’. Hamstring eccentric had a weak graded ‘C’ recommendation, and eccentric exercise for other body parts was ‘D’. Balance/proprioception exercise to reduce ankle and knee sprain injury was assigned a graded recommendation ‘D’.ConclusionsThe majority of perceptions and practices of premier league teams have a low level of evidence and low graded recommendation. This does not imply that these perceptions and practices are not important or not valid, as it may simply be that they are yet to be sufficiently validated or refuted by research.

This study examined the relationship between the frequency of playing actions performed during a soccer match and the recovery kinetics after the match. Time motion analyses were performed on 10 professional soccer players during 4 competitive matches (14 observations) to determine the number of playing actions completed by players. Subjective ratings, creatine kinase, and physical tests (countermovement jump [CMJ], isometric maximum voluntary contraction of the hamstrings, 6-second sprint on a nonmotorized treadmill) were performed before the match and 24 hours, 48 hours, and 72 hours after the match. During the 72-hour recovery period, CMJ, isometric strength of the hamstring muscles, and peak sprint speed significantly (p ≤ 0.05) decreased, whereas muscle soreness increased (p ≤ 0.05). Significant correlations were observed between the increase in muscle soreness and number of short sprints (<5 m) performed at 48 hours (r = 0.74; confidence interval [CI], 0.35-0.91; p < 0.01) and 72 hours (r = 0.57; CI, 0.05-0.84; p ≤ 0.05) after match play. A significant relationship (r = -0.55; CI, -0.84 to -0.03; p ≤ 0.05) was also observed between CMJ performance decrement at 24 hours and the number of hard changes in direction performed. Soccer match play resulted in significant neuromuscular fatigue for up to 72 hours after match and was dependent on the number of sprints and hard changes in direction performed during the match. Time motion analysis data currently used during a soccer match should quantify hard changes in direction, acceleration and deceleration phases to enable better estimations of postmatch fatigue.

In elite soccer, players are frequently required to play consecutive matches interspersed by 3 days and complete physical performance recovery may not be achieved. Incomplete recovery might result in underperformance and injury. During congested schedules, recovery strategies are therefore required to alleviate post-match fatigue, regain performance faster and reduce the risk of injury. This article is Part I of a subsequent companion review and deals with post-match fatigue mechanisms and recovery kinetics of physical performance (sprints, jumps, maximal strength and technical skills), cognitive, subjective and biochemical markers. The companion review will analyse recovery strategies used in contemporary professional soccer. Soccer involves many physically demanding activities including sprinting, changes in running speed, changes of direction, jumps and tackles, as well as technical actions such as dribbling, shooting and passing. These activities lead to a post-match fatigue that is linked to a combination of dehydration, glycogen depletion, muscle damage and mental fatigue. The magnitude of soccer match-induced fatigue, extrinsic factors (i.e. match result, quality of the opponent, match location, playing surface) and/or intrinsic factors (i.e. training status, age, gender, muscle fibre typology), potentially influence the time course of recovery. Recovery in soccer is a complex issue, reinforcing the need for future research to estimate the quantitative importance of fatigue mechanisms and identify influencing factors. Efficient and individualized recovery strategies may consequently be proposed.

The purpose of the present study was to investigate injury according to biological maturity in elite under-14 youth football players based at the National Football Institute, France. Over 10 seasons, injury incidence, severity and distribution were compared in 233 players classed according to individual biological maturity determined by skeletal age into three cohorts as early, normal and late maturers.A non-significant higher injury incidence was found in early and normal maturers compared with late maturers. In contrast, the latter group sustained a significantly higher incidence of major injuries compared with early maturers (0.3 vs 0.6 vs 0.9, P=0.039). A significantly higher incidence of osteochrondoses was reported in normal and late maturers (0.3 vs 0.7 vs 0.9, P=0.014), whereas tendinopathy incidence was greater in early and normal maturers (0.06 vs 0.08 vs 0.02, P=0.033). Early maturers incurred the highest incidence of groin strains and re-injuries (P<0.05). There was no significant difference between groups in the seasonal disposition of injury.Biological maturity status did not significantly affect overall injury incidence in elite French youth football players, although there were differences between maturity groups when patterns of injury location, type, severity and re-injury were analyzed.

In this study, the effects of a prolonged period of fixture congestion (8 successive official matches in 26-days) on physical performance and injury risk and severity in a professional soccer team were investigated. Computerised motion-analysis was used to analyse the overall distance covered and that run at light-(0.0-11.0 km•h -1 ); low-(11.1-14.0 km•h -1 ); moderate-(14.1-19.7 km•h -1 ) and high-intensities (≥19.8 km•h -1 ) for the team as a whole. Distances were measured in metres per minute. Information on match injuries was recorded prospectively. The overall distance covered varied across successive matches (p<0.001) as more distance was run in games 4 and 7 compared to 2 and 3 respectively ( When comparing match halves, there were no differences across games in overall or high-intensity distance covered and performance in these measures was similar for matches played before, during and after this period. Globally, no difference over the 8 games combined was observed between the reference team and opponents in any of the performance measures whereas the overall distance covered and that in low-(both p<0.001) and high-intensity running (p=0.040) differed in individual games. The incidence of match injury during the congested fixture period was similar to rates reported outside this period but the mean layoff duration of injuries was substantially shorter during the former (p<0.05). In summary, while the overall distance run and that covered at lower intensities varied across games, high-intensity running performance and injury risk were generally unaffected during a prolonged period of fixture congestion. These results might be linked to squad rotation and post-match recovery strategies in place at the present club.

In the formerly published part I of this two-part review, we examined fatigue after soccer matchplay and recovery kinetics of physical performance, and cognitive, subjective and biological markers. To reduce the magnitude of fatigue and to accelerate the time to fully recover after completion, several recovery strategies are now used in professional soccer teams. During congested fixture schedules, recovery strategies are highly required to alleviate post-match fatigue, and then to regain performance faster and reduce the risk of injury. Fatigue following competition is multifactorial and mainly related to dehydration, glycogen depletion, muscle damage and mental fatigue. Recovery strategies should consequently be targeted against the major causes of fatigue. Strategies reviewed in part II of this article were nutritional intake, cold water immersion, sleeping, active recovery, stretching, compression garments, massage and electrical stimulation. Some strategies such as hydration, diet and sleep are effective in their ability to counteract the fatigue mechanisms. Providing milk drinks to players at the end of competition and a meal containing high-glycaemic index carbohydrate and protein within the hour following the match are effective in replenishing substrate stores and optimizing muscle-damage repair. Sleep is an essential part of recovery management. Sleep disturbance after a match is common and can negatively impact on the recovery process. Cold water immersion is effective during acute periods of match congestion in order to regain performance levels faster and repress the acute inflammatory process. Scientific evidence for other strategies reviewed in their ability to accelerate the return to the initial level of performance is still lacking. These include active recovery, stretching, compression garments, massage and electrical stimulation. While this does not mean that these strategies do not aid the recovery process, the protocols implemented up until now do not significantly accelerate the return to initial levels of performance in comparison with a control condition. In conclusion, scientific evidence to support the use of strategies commonly used during recovery is lacking. Additional research is required in this area in order to help practitioners establish an efficient recovery protocol immediately after matchplay, but also for the following days. Future studies could focus on the chronic effects of recovery strategies, on combinations of recovery protocols and on the effects of recovery strategies inducing an anti-inflammatory or a pro-inflammatory response.