The Association Between Noncontact Injuries and the Acute—Chronic Workload Ratio in Elite-Level Athletes: A Critically Appraised Topic

Abstract

Clinical Scenario: Workload monitoring and management of an athlete is viewed by many as an essential training component to determine if an athlete is adapting to a training program and to minimize injury risk. Although training workload may be measured a variety of different ways, session rate of perceived exertion (sRPE) is often used in the literature due to its clinical ease. In recent years, sports scientists have been investigating sRPE as a measure of internal workload and its relationship to injury in elite-level athletes using a metric known as the acute:chronic workload ratio (ACWR). This critically appraised topic was conducted to determine if internal workload using the ACWR is associated with injury. Focused Clinical Question: In elite-level athletes, is there an association between the ACWR for sRPE and noncontact injuries? Summary of Search, Best Evidence Appraised, and Key Findings: The literature was searched for studies investigating the association between noncontact injuries and the sRPE ACWR in elite athletes. Three prospective cohort studies were included. Two studies found that high ACWR led to 2.0 to 4.5 times greater injury risk compared with a more balanced ACWR. One study found that low chronic workloads coupled with a low ACWR were associated with injury. Clinical Bottom Line: The majority of evidence suggests that when the acute workload exceeds the chronic workload, there is an increase in injury risk. The evidence also supports that a low chronic workload with a low ACWR should be considered as an injury risk factor. Strength of Recommendation: Based on the American Family Physician’s Strength of Recommendation Taxonomy, there is level A evidence to support the sRPE ACWR as a risk factor for noncontract injuries in elite athletes.

Wearable Technology and Analytics as a Complementary Toolkit to Optimize Workload and to Reduce Injury Burden

“…The heterogeneity of training intensities and durations suggests that athletes will either undertrain, over-train, or train at an optimal workload relative to their training intensities during the pre-lockdown period. Based on trends in the literature (Gabbett, 2010;Blanch and Gabbett, 2016;Bowen et al, 2020;Myers et al, 2020), we hypothesize that the incidence of injury will be primarily bimodal, particularly evident in the athletes that over-and undertrain relative to pre-lockdown intensities. The undertraining cohort will suffer injuries (oblique, groin, and hamstring strains) manifesting from the lack of progression in chronic workload.…”

Lower Extremity Musculoskeletal Injury in US Military Academy Cadet Basic Training: A Survival Analysis Evaluating Sex, History of Injury, and Body Mass Index

“…Supraphysiologic overloading also appears to have a temporal component in this population. 4 , 6 , 29 Our data further suggested that the temporal component differs between the sexes and begins to diverge early, at the more exhaustive events (eg, the Warrior Competition, 12-mile ruck). We speculate that the acute effort needed to complete these events (ie, load placed upon the tissues), particularly for female cadets, was far greater than the average (ie, chronic) load placed on tissues over the previous weeks.…”

Editorial: Acute: Chronic Workload Ratio: Is There Scientific Evidence?

“…In 2016, the International Olympic Committee (IOC) published a consensus statement (Soligard et al, 2016) that suggests the use of the ACWR approach for injury prevention. In addition, Myers et al (2020) reported level A evidence in support of the sRPE ACWR as an effective tool to prevent non-contact injuries in elite athletes. Despite evidence in favor of the ACWR approach, different authors have raised substantial criticism (Impellizzeri et al, 2020a,b;Wang et al, 2020).…”