FSI Selected Publications of the Week

1. Aerodynamics of the newly approved football for the English Premier League 2020-21 season.
Asai T, Hong S.

Faculty of Health and Sports Sciences, University of Tsukuba, Tsukuba, 305-8574, Japan. asai.takeshi.gf@u.tsukuba.ac.jp.

The official ball for the 2020-21 season of the English Premier League (Flight 2020, Nike) comprises just four panels with a complex panel shape and surface groove design. Aerodynamics testing in comparison to a 6-panel ball (Tsubasa 2020, Adidas) and conventional 32-panel ball (Pelada 2020, Molten) showed significantly higher drag in the supercritical region, and slightly smaller fluctuations of the side and lift forces.

Sci Rep. 2021 May 5;11(1):9578. doi: 10.1038/s41598-021-89162-y.


2. M. Biceps Femoris Long Head Architecture and Sprint Ability in Youth Soccer Players.
Ritsche P, Bernhard T, Roth R, Lichtenstein E, Keller M, Zingg S, Franchi MV, Faude O.

Hamstring muscle architecture may be associated with sprint performance and the risk of sustaining a muscle injury. This study in 85 under-13, 14 ans 15 players showed that the biceps femoris long head (BFlh) cross-sectional area (ACSA) correlated with 30-m sprint time and maximal velocity. Conversely, fascicle length and pennation angle did not correlate with sprint performance.

Int J Sports Physiol Perform. 2021 May 5:1-9. doi: 10.1123/ijspp.2020-0726. Online ahead of print.


3. Losing the Home Field Advantage When Playing Behind Closed Doors During COVID-19: Change or Chance?
Hill Y, Van Yperen NW.

Department of Psychology, University of Groningen, Groningen, Netherlands.

This study compared 1,000,000 randomized samples from the previous four seasons with the exact same number of matches played behind closed doors due to COVID restrictions in Europe’s four most elite soccer leagues (Germany, Spain, Italy, and England) at the end of the 2019/2020 season. Performance indices and referee decisions (except red cards) indeed changed to the detriment of the home team beyond the level of chance, but the proportion of points won by the home teams declined significantly only in Germany, driven by a meaningful increase in the proportion of goals scored by the away teams and the proportion of yellow cards given to the home teams.

Front Psychol. 2021 Apr 15;12:658452. doi: 10.3389/fpsyg.2021.658452. eCollection 2021.


4. Applying a holistic hamstring injury prevention approach in elite football: 12 seasons, single club study.
Suarez-Arrones L, Nakamura FY, Maldonado RA, Torreno N, Di Salvo V, Mendez-Villanueva A.

Department of Sport and Informatics, Section of Physical Education and Sport, Pablo de Olavide University, Sevilla, Spain. Football Science Institute, Granada, Spain.

An intervention in an elite club in Europe during 2 seasons consisting in a multicomponent, complex hamstrings injury prevention program with individual approaches based on player needs, management of training load, individualized physiotherapy treatment, and planned staff communication, all organized into different interventions throughout the week, achieved an overall hamstrings injury rate 3 times lower, with match injury rate 2.7 times lower, training injury rate 4.3 times lower, and injury burden almost 4 times lower, comparing with the previous 10 seasons. Also, re-injuries were 0% vs 10% previously.

Scand J Med Sci Sports. 2021 Apr;31(4):861-874. doi: 10.1111/sms.13913. Epub 2021 Jan 22.


5. Video analysis of concussion mechanisms and immediate management in French men’s professional football (soccer) from 2015 to 2019.
Cassoudesalle H, Laborde B, Orhant E, Dehail P.

Neurorehabilitation Unit, University Hospital of Bordeaux, Bordeaux, France.

The analysis of video recording of 36 from 41 reported concussions (0.44/1000 hours of match exposure) in the 1st and 2nd French Male leagues comprising seasons 2015/16-2018/19 showed that commonest playing action leading to concussion was aerial challenge (61%), and the main mechanism was head-to-head impact (47%). 28% of concussed players were not medically assessed on pitch and 53% returned to play the same match. Head-to-head impact was not associated with systematic medical assessment, nor with foul play. This means that detection of potential concussive head impacts and the immediate management of players possibly concussed during matches remain insufficient according to the international recommendations.

Scand J Med Sci Sports. 2021 Feb;31(2):465-472. doi: 10.1111/sms.13852. Epub 2020 Oct 23.


6. Video assistant referees (VAR): The impact of technology on decision making in association football referees.
Spitz J, Wagemans J, Memmert D, Williams AM, Helsen WF.

Department of Movement Sciences, Laboratory of Perception and Performance, Movement Control and Neuroplasticity Research Group, University of Leuven (KU Leuven) , Leuven, Belgium.

In 2195 competitive football matches across 13 countries, the VAR conducted 9732 checks for potential match-changing incidents, with the median duration of a check being 22 seconds. The checks resulted in a total of 795 reviews, with a median duration of 62.0 s for on-field reviews. The predictive odds for making the correct decision after VAR intervention were significantly higher than for the initial referee’s decision, with accuracy increasing from 92.1% to 98.3%.

J Sports Sci. 2021 Jan;39(2):147-153. doi: 10.1080/02640414.2020.1809163. Epub 2020 Aug 14.