Influence of prolonged running and training on tibial acceleration and movement quality in novice runners

Context: Changes in lower limb loading and movement quality after prolonged running and training periods might influence injury risks in runners. Objectives: To assess (1) the effects of a single prolonged run and a 3-week running training program on peak tibial acceleration (PTA) during running and Functional Movement Screen (FMS) criterion tests, and (2) the relationship between running volume during the 3-week training program and changes in PTA and FMS scores after training. Design: Case series. Setting: Research laboratory. Patients or Other Participants: Ten novice runners (age= 27 ± 7 years) with 15 ± 14 months of running experience, who ran on average 19.6 ± 4.8 km per week at a preferred pace of 7:05 ± 1:30 minutes per km. Main Outcome Measure(s): Participants completed a 30- minute submaximal prolonged treadmill run and 3-week training program with 25% increases in weekly running volume. Peak tibial acceleration and the deep-squat and active straight-leg- raise criterion FMS test scores were assessed before and after the prolonged run at enrollment and after the training program (ie, 3 testing sessions). Results: No differences in PTA or FMS scores were observed among the 3 testing times. Although the changes in PTA (r = 0.57) and FMS aggregate score (r = 0.15) were not significantly correlated with training volume, training volume explained 32% of the variance in the PTA change from before to after training. Conclusions: Our findings suggest that tibial acceleration and movement quality were not influenced by a single submaximal-effort prolonged run or a 3-week training period. However, novice runners who have a greater increase in running volume might be more susceptible to training-related changes in tibial acceleration than those whose running volume is less