Results The initial study population consisted of 24 soccer teams; one team declined to participate. The two clusters with 23 teams were randomised, resulting in 11 teams in the intervention group and 12 teams in the control group. Shortly after randomisation, the coach of one team from the intervention group refused to use The11 during the practice sessions. Data of 456 players were analysed, 223 in the intervention group and 233 in the control group (figure 1). During the intervention season, 29 players (6.4%) were lost to follow-up, mainly because they ended their soccer career or because they changed the team or club. All their available data were included in the analysis of the effects of the intervention programme. No significant difference in dropout rate was found between the intervention group (n=11, 4.9%) and the control group (n=18, 7.7%). Baseline characteristics of the players in the two study groups were similar, except for height and weight (table 2). Baseline data from dropouts and players with complete follow-up were not significantly different. Exposure and injury characteristics During the season, the players were involved in a total of 31 518 h of practice time and 12 734 h of match time, resulting in a total exposure time of 44 252 h. The mean practice and match times per player were 69.1 and 27.9 h, respectively, during the 33 weeks of the competition season. In all, 427 injuries were recorded, affecting 274 of the 456 players (60.1%). The most commonly injured body parts (n=408) were ankle (19.1%), posterior upper leg (15.9%), knee (15.7%), anterior upper leg (10.5%) and groin (10.5%). The overall injury incidence for both groups was 9.6 (8.8–10.6) injuries per 1000 player hours; 3.4 (2.8–4.1) in practice sessions and 21.9 (19.5– 24.6) in matches. Compliance Teams in the intervention group completed the intervention programme in 73% of all practice sessions (median 47, range 0–63), corresponding to performing The11 an average of 1.3 times per week. Players completed the exercises in 71% of the practice sessions they attended. Player absence meant that The11 was performed an average of 31 times per season (median 35, range 0–63). None of the teams in the control group regularly performed a structured prevention programme comparable to the intervention programme. Effects of the intervention programme As table 3 shows, overall injury incidences were almost equal for both groups: 9.6 per 1000 sports hours (8.4–11.0) for the intervention group and 9.7 (8.5–11.1) for the control group, as well as incidences of match and practice injuries. Nor were significant differences found in injury severity. None of the other outcomes showed significant differences between the two groups, apart from the percentage of knee injuries. However, after a Sidak correction for multiple testing (n=6) this result should be interpreted Figure 1 Flow diagram of the study population. Table 2 Baseline characteristics of the soccer players (n=456) Age (years) Height (m)* Weight (kg)* BMI (kg/m²) Soccer experience (years) Injury history (%) - Injured in previous year - Injured at start of season Intervention group (mean±SD) 24.4±4.1 1.85±0.1 79.1±7.4 23.2±1.8 17.2±4.3 73.4 (n=214) 11.7 (n=223) Control group (mean±SD) 25.1±4.3 1.82±0.1 77.4±7.4 23.3±1.8 17.7±4.6 64.7 (n=221) 11.6 (n=233) *Significantly different between the intervention and control group. nummer 5 | december 2012 | Sport & Geneeskunde 9 Pagina 8
Pagina 10Heeft u een whitepaper, nxtbook of digitale jaarverslagen? Gebruik Online Touch: onderwijscatalogus naar een digitale publicatie omzetten.
Sport & Geneeskunde nummer 5 | December 2012 Lees publicatie 18Home