Danger zone assessment in small-sided recreational football: providing data for consideration in relation to COVID-19 transmission

Abstract

During the COVID-19 pandemic, physical inactivity has increased, and a wide range of sporting activities locked down, with possible long-term implications for public health. Football is the most popular sport worldwide, and recreational football training leads to broad-spectrum health effects. Football is, however, deemed a contact sport with frequent close contact important to consider during COVID-19 pandemic.ObjectivesThis study investigated time spent with close contact (danger zone (DZ) within 1.5 m), number of contacts and time per contact, and compared game formats in recreational small-sided football games for young and adult male football players.MethodsMovement analyses were performed on 10 Hz Global Positioning System (GPS) data collected during various small-sided football games prior to the COVID-19 outbreak.ResultsTime spent in the DZ was 4.3–7.9 s/h per per cent infected players, corresponding to 34.3–114.8 s/h if one player was infected. Number of contacts with one infected player was 23.5–87.7 per hour, with an average contact time of 1.1–1.4 s, and a total number of contacts of 311–691 per hour with all players. 53%–65% of all contacts were shorter than 1 s and 77%–85% shorter than 2 s. Trivial to small effects were found for number of participants and area per player, whereas standard of play and playing with/without boards had no effect.ConclusionThis study demonstrated that during small-sided football limited time is spent within DZ and that player contacts are brief. Recreational football may therefore more appropriately be deemed as sporting activity with brief, sporadic contact.

A video-based analysis of situations bearing the risk of respiratory disease transmission during football matches

“…Transmission risk is also a direct function of contact duration 17 . In our study, nearly all contacts lasted for less than 3 s. This finding is in line with results of Randers, Knudsen, Thomasen, Panduro, Larsen, Mohr, Milanovic, Krustrup and Andersen 11 who analysed the time amateur players spend within a radius of 1.5 m to another player. Approximately 90% of contacts within this risk zone were shorter than 3 s, and less than 0.5% of all contacts lasted longer than 10 s. The average contact time was slightly above 1 s. Similarly, Goncalves, Mendes, Folgado, Figueiredo, Travassos, Barros, Campos-Fernandes, Beckert and Brito 12 analysed a professional soccer match by means of a tracking system.…”

“…Video-analysis of 21 matches with 34 potentially infectious players in the same study revealed that football-specific contacts were likely not sufficient to transmit the virus. In order to estimate the potential infection risk of players, Randers, Knudsen, Thomasen, Panduro, Larsen, Mohr, Milanovic, Krustrup and Andersen 11 analysed GPS data in youth (8 and 9 years old) and adult (20–33 years old) recreational players with regard to the time and number of close contacts (within a 1.5 m zone) during different small-sided game formats (3 vs. 3 to 8 vs. 8). The average duration of a close contact was slightly more than 1 s. The authors concluded that during small-sided football the time spent within potentially dangerous zones is brief.…”

Risk of SARS-CoV-2 transmission from on-field player contacts in amateur, youth and professional football (soccer)

“…During small-sided games in recreational adult and youth football, the time a player spent within a radius of 1.5 m (risk zone) was shorter than 3 s 90% of the time. 29 In a professional football match tracking systems showed that the average exposure time per pair of individuals was 32 s. 1 In a more specific approach based on a video analysis, all transmission-relevant physical contacts that occurred during 50 football matches, both between and within players, were examined. 3 It was concluded that aerosol and droplet producing activities (speaking, shouting, spitting) and direct contacts to mucous membranes are infrequent in football matches.…”

Soccer in the time of COVID-19: 1 year report from an Italian top league club, March 2020–February 2021

“…Actually, during a soccer match, players cannot voluntarily avoid the contact with other players, and intense physical exercise can result in incremented release of isolated droplets [ 16 ]. However, the total exposure of a soccer player within a potentially risky zone of 1.5 m from a given opponent player was estimated to be limited in time (34–115 s/h), during recreational small-sided football games [ 17 ]. To a certain extent, even the contact with ball and other equipment can lead to infection, although there is uncertainty about the role of fomites in COVID-19 transmission [ 18 ].…”