Research Online Research Online Subjective Wellness, Acute: Chronic Workloads, and Injury Risk in Subjective Wellness, Acute: Chronic Workloads, and Injury Risk in College Football College Football

Abstract Acute:chronic workload ratios (ACWRs) are associated with injury risk across team sports. In this study, one season of workload and wellness data from 42 collegiate football players were retrospectively analyzed. Daily 7:21 day exponentially weighted moving average (EWMA) ACWRs were calculated, and z-score fluctuations (“normal,” “better,” and “worse”) in sleep, soreness, energy, and overall wellness were assessed relative to the previous day ACWRs and considered as an interactive effect on the risk of noncontact injury within 0–3 days. Fifty-five noncontact injuries were observed, and injury risks were very likely higher when ACWRs were 2 SDs above (relative risk [RR]: 3.05, 90% confidence interval [CI]: 1.14–8.16) and below (RR: 2.49, 90% CI: 1.11–5.58) the mean. A high ACWR was trivially associated (p < 0.05) with “worse” wellness (r = −0.06, CI: −0.10 to −0.02), muscle soreness (r = −0.07, CI: −0.11 to −0.03), and energy (r = −0.05, CI: −0.09 to −0.01). Feelings of “better” overall wellness and muscle soreness with collectively high EWMA ACWRs displayed likely higher injury risks compared with “normal” (RR: 1.52, 90% CI: 0.91 to 2.54; RR: 1.64, 90% CI: 1.10–2.47) and likely or very likely (RR: 2.36, 90% CI: 0.83 to 674; RR: 2.78, 90% CI: 1.21–6.38) compared with “worse” wellness and soreness, respectively. High EWMA ACWRs increased injury risk and negatively impacted wellness. However, athletes reporting “better” wellness, driven by “better” muscle soreness presented with the highest injury risk when high EWMA ACWRs were observed. ABSTRACT 6 Acute:chronic workload ratios (ACWR) are associated with injury risk across team sports. In 7 this study, one season of workload and wellness data from forty-two collegiate football players 8 were retrospectively analysed. Daily 7:21 day exponentially weight moving average (EWMA) 9 ACWR were calculated, and z-score fluctuations (“normal” “better” and “worse”) in sleep, 10 soreness, energy and overall wellness were assessed relative to the previous days ACWR and 11 considered as an interactive effect on the risk of non-contact injury within 0-3 days. 12 55 non-contact injuries were observed and injury risks were very likely higher when 13 ACWR’s were 2SD’s above (RR: 3.05, 90% CI: 1.14 to 8.16) and below (RR: 2.49, 90% CI: 14 1.11 to 5.58) the mean. A high ACWR was trivially associated (p<0.05) with “ worse ” wellness 15 (r = -0.06, CI: -0.10 to -0.02), muscle soreness (r = -0.07, CI: -0.11 to -0.03), and energy (r = - 16 0.05, CI: -0.09 to -0.01). Feelings of “better ” overall wellness and muscle soreness with 17 collectively high EWMA ACWRs displayed likely higher injury risks compared to “ normal ” 18 (RR: 1.52, 90% CI: 0.91 to 2.54; RR: 1.64, 90% CI: 1.10 to 2.47) and likely or very likely (RR: 19 2.36, 90% CI: 0.83 to 674; RR: 2.78, 90% CI: 1.21 to 6.38) compared to “ worse ” wellness and 20 soreness respectively. highest injury risk when high EWMA ACWR were observed. This suggests that practitioners are responsive to, and/or athletes are able to self-modulate workload activities.