Association of daily workload, wellness, injury and illness during tours in international cricketers

Purpose: To examine the relationship between player internal workloads, daily wellness monitoring, injury and illness in a group of elite adolescent cricketers during overseas competitions. Methods: Thirty-nine male international adolescent cricketers (17.5 0.8 yr) took part in the study. Data was collected over five tours across a three-year period (2014-2016). Measures of wellness were recorded, and daily training loads calculated using session-rating of perceived exertion. The injury and illness status of each member of the squad was recorded daily. Acute and chronic workloads were calculated using three days and fourteen days moving averages. Acute workloads, chronic workloads, and acute chronic workload ratios (ACWR) were independently modelled as fixed effects predictor variables. Results: In the subsequent week, a high 3-day workload was significantly associated with an increased risk of injury (Relative Risk [RR] = 2.51; CI = 1.70 to 3.70). Similarly, a high 14-day workload was also associated with an increased risk of injury (RR = 1.48; CI = 1.01 to 2.70). Individual differences in the load injury relationship were also found. No clear relationship between the ACWR and injury risk was found, but high chronic workloads combined with a high or low ACWR showed an increase probability of injury compared to moderate chronic workloads. There were also trends for sleep quality and cold symptoms worsening the week before an injury occurred. Conclusion: Although there is significant individual variation, short term high workloads and changing in wellness status appear to be associated with injury risk.