# Injury Incidence and Pattern in Elite Young Male and Female Trail Runners
## 3 Results  
The descriptive analysis of the training time shows that the mean weekly hours dedicated to training is 8.7 \(\pm\) 2.4 h, in which 68.6% of the surveyed athletes dedicate between 6 and 10 h/week to training. The results of these data disaggregated by sex showed a similar load: 8.8 \(\pm\) 2.4 h/week in male and 8.6 \(\pm\) 2.3 h/week in female athletes. Globally, results showed that 6 athletes out of 51 (2 male and 4 female trail runners) did not report any injury, which indicates an incidence of 88.2%. Among these, athletes reporting 1 or 2 occurrences predominated (33.3% and 29.4% respectively). The remaining 45 athletes accounted for a total of 95 injuries. The analysis of practice hours indicated 2.2 \(\pm\) 1.8 injuries per 1000 h of practice hours. The results also showed that most occurred in the following regions: ankles (49.5%), knees (17.9%), and lower legs (9.5%), as shown in Table 1. The \(z\) test showed significant differences between ankle injuries compared to the rest of the regions (\(p\)\(<\) 0.001; ES = 0.462). The analysis by sex shows that the number of reported athletes injured was greater for males (33 out of 35; 94.3%) than for female runners (12 out of 16; 75.0%). In regards to the incidence by training hours, male runners reported 2.3 \(\pm\) 1.9 injuries every 1000 h, compared to 1.8 \(\pm\) 1.3 in female runners. The body regions with greater prevalence in male athletes were ankle (54.3%), significantly larger than the rest of body regions (\(p\) < 0.001; ES = 0.520). In female athletes, the ankle remains the most affected region (36%), followed by the lower leg (20%) and the knee (16%). However, no significant differences were observed between any regions, so percentages were more distributed in female runners. Comparing between sexes, no significant differences were observed. The analysis according to the moment of occurrence showed that trail runners got injured most during training and competitions (40.0% and 33.7%, respectively), as shown in Table 2. The remaining activities were indirect injuries (2.1%), and not at all related to trail running, accounting for 24.2% of the total. The results segmented by sex showed very similar percentages. In regards to the body region most affected, all injuries to the toes were directly related injuries and occurred in competition, whereas 52.9% of knee injuries occurred in training versus 11.8% produced in competition. In the case of ankle injuries, 40.4% occurred in competition, and 42.6% occurred during training. Regarding the type of injury, 57.0% were new (\(p\) < 0.001; ES = 0.758), 29.5% recurrent (\(p\) = 0.016; ES = 0.016) and 12.5% exacerbation injuries, with significant differences among them. While this trend is similar in male athletes, with significant differences in new injuries (\(p\) < 0.001; ES = 0.829), the percentages of recurrent and exacerbation injuries in female athletes are both 24.0%, with new injuries being only significantly higher (52.0%, \(p\) = 0.005; ES = 0.585). The ankle was the body region with more new injuries (59.8%), followed by 34.0% recurrent and 6.4% exacerbation injuries. On the other hand, of the 17 knee injuries, 64.7% were new, 17.6% recurrent, and 17.6% exacerbation injuries. The mode of onset revealed that nearly half of the injuries reported were caused by acute sudden onset (49.5%), followed by repetitive sudden onset (34.7%), and repetitive gradual onset (15.8%). The \(z\)-test showed significant differences for acute sudden onset (\(p\) < 0.001; ES = 0.722), and repetitive sudden onset (\(p\) = 0.001; ES = 0.316). Concerning incidence by sex, most of the injuries in male runners were caused by acute sudden onset (55.7%, \(p\) = 0.001; ES = 0.734), followed by repetitive sudden onset (30.0%, \(p\) = 0.027; ES = 0.267) and repetitive gradual onset (14.3%).