Neuromuscular conditioning strategies used, incidence, severity, and factors associated with musculoskeletal injuries sustained by professional runners in North Rift, Kenya

Abstract

Background: Professional runners are prone to sustaining musculoskeletal injuries in training and competition. Factors that predispose them to sustaining these injuries are unclear with training errors being implicated in most injuries. Neuromuscular conditioning is the performance of exercises that improve proprioception, flexibility, strength and balance. These have the potential of mitigating the injuries that runners sustain. Literature on the neuromuscular conditioning strategies used by professional runners in North Rift Kenya is limited. Objective: To describe the neuromuscular conditioning strategies used, and to determine the incidence, severity, and factors associated with musculoskeletal injuries sustained, by professional runners in North Rift, Kenya. Methods: A prospective study was conducted at training camps in North Rift, Kenya. Randomly sampled, 89 professional runners were interviewed at the beginning of the season and their anthropometric measurements taken. Participants were provided with training diaries. Follow up interviews by phone were conducted two monthly for one year to collect data on injuries, training and potential risk factors for injury. Neuromuscular conditioning strategies used were summarized in tables, injury incidence was calculated as injuries per 1000 hours, and severity as time lost in days. Tests of significance were used to calculate associations between variables and injury incidence and severity. For categorical variables such as neuromuscular conditioning strategies used, gender and BMI, Chi square and Fisher‟s exact tests were used. Wilcoxon rank sum tests were used for continuous variables such as runners‟ experience in years. Results: Per week on average, 88 runners spent 174 minutes on slow distance endurance training, 83 spent 87 minutes on stretches, 40 spent 42 minutes on plyometric strength training, and 45 spent 14 minutes on single leg balance training. Injury incidence was 42.40 injuries per 1000 hours of training (95% CI: 33.33, 51.47). Of the 57 (64.04%) runners who sustained injuries, 43 (75.44%) suffered time loss injuries. Median time lost was 5 days (IQR: 1, 14). Neuromuscular conditioning strategies used, age, gender, running experience, injury history, BMI, lower limb flexibility, were not significantly associated with the incidence of injury. Runners who practiced single leg balance training and those who practiced plyometric strength training sustained significantly more slight to mild injuries than moderate to severe injuries (p = 0.005, p = 0.026 respectively). Conclusion: Professional runners in North Rift spent most of their training time on endurance and flexibility training with the least time spent on strength and balance training respectively. They sustained largely moderately severe injuries at a rate of 42.4 injuries per 1000 hours of training. Differences in neuromuscular conditioning strategies used, athletic experience, demographic and anthropometric factors were not significantly associated with the incidence of injuries. Runners who did single leg balance or plyometric strength training tended to have less severe injuries. Recommendations: Runners should perform single leg balance training and plyometric strength training to mitigate the severity of running injuries they may suffer.