Towards real-world biomechanical detection of fatigue, energy, and injury in runners using Wearable Trunk Accelerometry

[摘要] ENGLISH ABSTRACT: Running continues to be an extremely popular form of exercise and sport. Unfortunately,many runners, both recreational and competitive, fail to meet their fitness and performancegoals due to sustaining an overuse injury. Such overuse injuries can be due to numerousenvironmental factors and internal factors. Therefore, any approach to identifying andminimizing these risk factors in real-life running conditions will help runners to reach theirtraining goals while also to regain running's numerous health benefits.Running requires minimal equipment and can be performed on practically any terrain.Ideally, measurements of a runner's mechanics should follow the runner through his or hertypical training environment and be unrestricted to location. However, such measurementsmay require a totally different experimental approach compared to those traditionallyperformed in the laboratory (i.e. capture and analyse every stride of the runner outdoorsrather than providing only a 'snapshot' view).Over two decades ago it was acknowledged that obtaining objective data in real-lifeenvironments using wearable technology is of high priority with potential to advancerunning performance while also reducing injury risk. Even with recent and rapidtechnology advancements, there remains a paucity of literature linking the fields ofwearable technology with running related performance and injury risk. Thus, the globalobjective of this thesis is to expand understanding with regards to detectingfatigue-, energy-, and injury-related dynamic instability and dynamic loadingin runners using wearable trunk accelerometry (WTA), with transferability to'real-world' ecologically valid settings.In the first part of this thesis, we performed two indoor laboratory studies focusing firstlyon the biomechanical, and secondly on the energetic aspects of running. Study I (chapter2) biomechanically confirmed a fatigue-ability hypothesis, showing that runners incur aloss of stability from running-induced fatigue specific to laboratory-controlled treadmillrunning conditions at fixed speeds. Study II (chapter 3) physiologically confirmeda cost of instability hypothesis, revealing that certain aspects of dynamic stability areenergetically advantageous to endurance running.In the second part of this thesis we performed two outdoor over-ground runningexperiments. Study III (chapter 4) experimentally showed that running on an irregularoutdoor surface such as wood-chip trails disrupts aspects of stability specific to themediolateral direction. Study IV (chapter 5) partially confirmed a fatigue-ability andinjury hypothesis, showing that runners with history of medial tibial stress syndrome(MTSS) incur a loss of stability in the mediolateral direction from outdoor track-runningat self-selected speeds.Finally, the general discussion (chapter 6) brings together findings with practicalimplications directed at runners, researchers, and practitioners. In addition, somepreliminary data with regards to running stability before, during, and after an endurancetraining program are provided, with potential insights and future directions aimed atperformance and injury detection. Overall, this doctoral thesis contributes to abetter understanding of a runner's dynamic stability and loading in relation tofatigue, energy and injury using wearable trunk accelerometry.

[发布机构] Stellenbosch University