Considerations in interpreting neuromuscular state in elite level Australian Rules football players

Abstract

ObjectivesExamine the influence of test modality, season stage, match load and physical qualities on the interpretation of neuromuscular function (NF) post Australian Rules Football (ARF) matches. DesignRepeated measures design. MethodsThirty-two elite ARF players’ NF was assessed 72h following competitive matches (7±2) via the counter movement jump (CMJ) and isometric mid-thigh pull (IMTP). Influence of season stage, external load parameters (GPS; 10Hz) and moderating influences of lower body strength (LBS), lower body power (LBP) and intermittent exercise capacity upon NF recovery were assessed using linear mixed effects models. ResultsModerate negative seasonal trends were evident for both rate of force development (RFD) 0−100ms (d=−0.86, 95%, CI: ±0.57) and 0−200ms (d=−0.76, CI: ±0.64). Significant but trivial effects of match load were observed between one standardised unit increase in high speed running (HSR) versus CMJ: Force at zero velocity (d=0.12, CI: ±0.12), and sum of high intensity accelerations and CMJ: Eccentric deceleration RFD (d=−0.18, CI: ±0.14). Accounting for baseline LBS better explained (weight of evidence: W=87%) seasonal trends observed in IMTP: peak force, with lower LBS showing greater capacity for improvement. Positive moderating influences were observed with baseline LBS and LBP (W=91 & 75%) on CMJ: eccentric mean power responses to HSR, and CMJ: jump height responses to very-HSR, respectively. ConclusionsInterpretation of athlete NF responses is complicated by the inconsistent and interacting influence of contextual factors (assessment modality, stage of season, load), in-particular higher baseline LBS and LBP may improve acute load related responses of NF.