Time–motion analysis is a valuable data-collection technique used to quantify the physical match performance of elite soccer players. For over 40 years, researchers have adopted a “traditional” approach when evaluating match demands by simply reporting the distance covered or time spent along a motion continuum of walking through to sprinting. This methodology quantifies physical metrics in isolation without integrating other factors, and this ultimately leads to a 1-dimensional insight into match performance. Thus, this commentary proposes a novel “integrated” approach that focuses on a sensitive physical metric such as high-intensity running but contextualizes this in relation to key tactical activities for each position and collectively for the team. In the example presented, the integrated model clearly unveils the unique high-intensity profile that exists due to distinct tactical roles, rather than 1-dimensional “blind” distances produced by traditional models. Intuitively, this innovative concept may aid coaches’ understanding of the physical performance in relation to the tactical roles and instructions given to the players. In addition, it will enable practitioners to effectively translate match metrics into training and testing protocols. This innovative model may well aid advances in other team sports that incorporate similar intermittent movements with tactical purpose. Evidence of the merits and application of this new concept is needed before the scientific community accepts this model as it may well add complexity to an area that conceivably needs simplicity.
Paul S. Bradley and Jason D. Vescovi
There is no methodological standardization of velocity thresholds for the quantification of distances covered in various locomotor activities for women’s soccer matches, especially for high-speed running and sprinting. Applying velocity thresholds used for motion analysis of men’s soccer has likely created skewed observations about high-intensity movement demands for the women’s game because these thresholds do not accurately reflect the capabilities of elite female players. Subsequently, a cohesive view of the locomotor characteristics of women’s soccer does not yet exist. The aim of this commentary is to provide suggestions for standardizing high-speed running and sprint velocity thresholds specific to women’s soccer. The authors also comment on using generic vs individualized thresholds, as well as age-related considerations, to establish velocity thresholds.
Darren J. Paul, Paul S. Bradley, and George P. Nassis
Time-motion analysis is a valuable data-collection technique used to quantify the match running performance of elite soccer players. However, interpreting the reductions in running performance in the 2nd half or temporarily after the most intense period of games is highly complex, as it could be attributed to physical or mental fatigue, pacing strategies, contextual factors, or a combination of mutually inclusive factors. Given that research in this domain typically uses a reductionist approach whereby match running performance is examined in isolation without integrating other factors, this ultimately leads to a 1-dimensional insight into match performance. Subsequently, a cohesive review of influencing factors does not yet exist. The aim of this commentary is to provide a detailed insight into the complexity of match running performance and its most influential factors.
Jack D. Ade, Jamie A. Harley, and Paul S. Bradley
To quantify the physiological responses, time–motion characteristics, and reproducibility of various speed-endurance-production (SEP) and speed-endurance-maintenance (SEM) drills.
Sixteen elite male youth soccer players completed 4 drills: SEP 1 v 1 small-sided game (SSG), SEP running drill, SEM 2 v 2 SSG, and SEM running drill. Heart-rate response, blood lactate concentration, subjective rating of perceived exertion (RPE), and time–motion characteristics were recorded for each drill.
The SEP and SEM running drills elicited greater (P < .05) heart-rate responses, blood lactate concentrations, and RPE than the respective SSGs (ES 1.1–1.4 and 1.0–3.2). Players covered less (P < .01) total distance and high-intensity distance in the SEP and SEM SSGs than in the respective running drills (ES 6.0–22.1 and 3.0–18.4). Greater distances (P < .01) were covered in high to maximum acceleration/deceleration bands during the SEP and SEM SSGs than the respective running drills (ES 2.6–4.6 and 2.3–4.8). The SEP SSG and generic running protocols produced greater (P < .05) blood lactate concentrations than the respective SEM protocols (ES 1.2–1.7). Small to moderate test–retest variability was observed for heart-rate response (CV 0.9–1.9%), RPE (CV 2.9–5.7%), and blood lactate concentration (CV 9.9–14.4%); moderate to large test–retest variability was observed for high-intensity-running parameters (CV > 11.3%) and the majority of accelerations/deceleration distances (CV > 9.8%) for each drill.
The data demonstrate the potential to tax the anaerobic energy system to different extents using speed-endurance SSGs and that SSGs elicit greater acceleration/deceleration load than generic running drills.
Paul S. Bradley, Carlos Lago-Peñas, and Ezequiel Rey
To evaluate match performances of substitute players using different research designs.
English Premier League matches were analyzed using a multiple-camera system. Two research designs were adopted: an independent-measures analysis comparing the match-performance characteristics of players completing the entire match (n = 810) vs substitutes (n = 286) and the players they replaced (n = 286) and a repeated-measures analysis comparing the same players completing full matches vs those in which they were introduced as a substitute (n = 94).
Most substitutions (P < .05) occurred at halftime and between the 60- to 85-min vs all first-half periods and the remaining second-half periods (effect size [ES]: 0.85–1.21). These substitutions become more (P < .01) offensive (eg, more attacking positions were introduced) in relation to the positions introduced as the half progressed (ES: 0.93–1.37). Independent-measures analysis indicated that high-intensity running was greater (P < .01) in substitutes compared with players who either completed the entire match or were replaced (ES: 0.28–0.67), but no differences were evident for pass-completion rates (ES: 0.01–0.02). Repeated-measures analysis highlighted that players covered more (P < .01) high-intensity running when they were introduced as substitutes compared with the equivalent period of the second- but not the first-half period (ES: 0.21–0.47). Both research designs indicated that attackers covered more (P < .05) high-intensity running than peers or their own performances when completing the entire match (ES: 0.45– 0.71).
Substitutes cover greater high-intensity-running distance; this was particularly evident in attackers, but pass-completion rates did not differ for any position. This information could be beneficial to coaches regarding optimizing the match running performances of their players, but much more work needs to be undertaken to investigate the overall impact of substitutes (physical, technical indicators, and contribution to key moments of matches).
Michael D. Bush, David T. Archer, Robert Hogg, and Paul S. Bradley
To investigate match-to-match variability of physical and technical performances in English Premier League players and quantify the influence of positional and contextual factors.
Match data (N = 451) were collected using a multicamera computerized tracking system across multiple seasons (2005–06 to 2012–13). The coefficient of variation (CV) was calculated from match to match for physical and technical performances in selected positions across different match contexts (location, standard, and result).
Wide midfielders demonstrated the greatest CVs for total distance (4.9% ± 5.9%) and central midfielders the smallest (3.6% ± 2.0%); nevertheless, all positions exhibited CVs <5% (P > .05, effect size [ES] 0.1–0.3). Central defenders demonstrated the greatest CVs and wide midfielders the lowest for both high-intensity running (20.2% ± 8.8% and 13.7% ± 7.7%, P < .05, ES 0.4–0.8) and sprint distance (32.3% ± 13.8% and 22.6% ± 11.2%, P < .05, ES 0.5–0.8). Technical indicators such as tackles (83.7% ± 42.3%), possessions won (47.2% ± 27.9%), and interceptions (59.1% ± 37.3%) illustrated substantial variability for attackers compared with all other positions (P < .05, ES 0.4–1.1). Central defenders demonstrated large variability for the number of times tackled per match (144.9% ± 58.3%) and passes attempted and received compared with other positions (39.2% ± 17.5% and 46.9% ± 20.2%, P < .001, ES 0.6–1.8). Contextual factors had limited impact on the variability of physical and technical parameters.
The data demonstrate that technical parameters varied more from match to match than physical parameters. Defensive players (fullbacks and central defenders) displayed higher CVs for offensive technical variables, while attacking players (attackers and wide midfielders) exhibited higher CVs for defensive technical variables. Physical and technical performances are variable per se regardless of context.
Mário A.M. Simim, Gustavo R. da Mota, Moacir Marocolo, Bruno V.C. da Silva, Marco Túlio de Mello, and Paul S. Bradley
We investigated the match demands (distances covered and acute physiological responses) of amputee soccer and its impact on muscular endurance and power. Measures such as heart rate, blood lactate concentration, subjective rating of perceived exertion, and time-motion characteristics were recorded in 16 Brazilian amputee soccer players during matches. Before and after matches, players completed a battery of tests: push-ups, countermovement vertical jump performance, and medicine ball throwing. Small differences were found between the first and second half for the distance covered in total and across various speed categories. Heart rate responses, blood lactate concentrations, and peak speed did not differ between halves, and all neuromuscular performance measures decreased after the match particularly after push-ups, although the rating of perceived exertion increased markedly compared with prematches. Although match physical performances were consistent across halves, the overall demands impaired test performance, especially for upper limb and closed kinetic chain exercise.