An investigation into the relationship between training load and injury and illness in competitive swimming

Introduction: In competitive swimming, optimal performance relies heavily on maximising specific capacities to succeed in competition. The training demands for this optimisation require overreaching interspersed with recovery. Elite coaches rely on their previous experience, coupled with wider sports science support to plan, organise and periodise training cycles. However, despite these practices, competitive swimmers often train and compete with persistent health problems. Training load monitoring and injury/illness surveillance practices are a necessary process in counteracting training load-related errors and designing and implementing injury/illness prevention strategies.

Aims: (1) To explore best practice in monitoring training load and injury and illness surveillance in competitive swimming environments and (2) To investigate the relationships between training load and injury and illness in competitive swimmers.

Methods: Five studies were conducted in this programme of research. Firstly, a systematic review explored the prevalence of training load monitoring practices within competitive swimming research. The review also investigated the relationship between training load and pain, injury, and illness within competitive swimming research (Chapter two). Secondly, an online survey was used to determine the current applied training load monitoring and injury surveillance practices within competitive swimming environments (Chapters three and four). Subsequently, an integrated training load monitoring and injury/illness surveillance system for use within competitive swimming environments was designed, implemented, and reported, while a qualitative end-user evaluation process was additionally executed (Chapter five). Finally, a prospective, longitudinal data collection was conducted using the integrated training load and injury/illness surveillance system. The resulting data were analysed to explore the relationship between training load and aggregates of training load and injury and illness in competitive swimmers (Chapter six).

Results: The systematic review identified no clear evidence of an association between training load and pain, while there may be some evidence to suggest a relationship between training load and injury and illness. An international survey of training load monitoring practices found that 83.9% of those surveyed employed some element of training load monitoring. Both internal and external training load monitoring were used in 80.8% of those cases, with swim volume (mileage) (96.2%) and session rate of perceived exertion (sRPE) (92.3%) most frequently used. Thematic analysis highlighted that “stakeholder engagement”, “resource constraints” or “functionality and usability of the systems” were shared barriers to the training load monitoring process. An international survey of injury surveillance practices found that 68.1% of practitioners participated in injury surveillance. A recognised definition for injury was used in 86.6% of those cases. Injury surveillance was identified as very effective at identifying injury trends by 66.6% of those surveyed, while previous injury history and training load data were perceived to be influential in preventing injury. Athlete adherence to training load monitoring was impacted by “process constraints” and “data access and control”. Practitioners highlighted communication and cooperation amongst stakeholders, layering context to the data, maintaining data integrity and the coach’s influence in the monitoring process as being important to the monitoring/surveillance process. Prospective training load and injury/illness monitoring highlighted that the average weekly volume was 33.5 ± 12.9 km. The weekly total training load (AU) averaged 3,838 ± 1,616.1 AU, with 85% of that load coming from swimming. A total of 60 medical attention illnesses and 58 medical attention injuries were recorded during the observation period. Statistical analyses found no association between Weekly Pool Volume (km), 4-week Rolling Pool Volume (km), Weekly Total Load Training (AU) and 4-week Rolling Total Training Load (AU) and ACWR and medical attention injury and illness. This occurred irrespective of a 0-day or 7-day lag time.

Conclusions: The findings of this programme of research do not support an association between training load and medical attention injury and illness in the studied cohort of athletes. Monitoring training load and injury/illness surveillance have their own unique challenges which must be navigated during the design and implementation stages. Periodic end-user evaluations are necessary to meet the demands of dynamic sporting environments. The sRPE method of monitoring training load should be employed in practical environments to guide coaches’ periodisation plans and to compare the coaches’ planned training volume and intensity against what the athlete is subjectively experiencing. sRPE is also beneficial as it can transcend all aspects of a modern-day swim programme. Dryland activities, competition and swim training load can be quantified utilising the same method, allowing for an accurate measure of total training load.