Markers of Postmatch Fatigue in Professional Rugby League Players

Abstract

The aim of the present study was to identify neuromuscular, biochemical, and endocrine markers of fatigue after Rugby League match play. Seventeen elite Rugby League players were monitored for a single match. Peak rate of force development (PRFD), peak power (PP), and peak force (PF) were measured during a countermovement jump (CMJ) on a force plate pre and postmatch play. Saliva and blood samples were collected 24 hours prematch, 30 minutes prematch, 30 minutes postmatch, and then at 24-hour intervals for a period of 120 hours to determine plasma creatine kinase concentration ([CK]) and salivary cortisol concentration ([sCort]). There were significant (p < 0.05) decreases in PRFD and PP up to 24 hours postmatch with PF significantly (p < 0.05) decreased immediately postmatch. The [sCort] significantly (p < 0.05) increased from 24 hours prematch to 30 minutes prematch and up to 24 hours postmatch compared with 24 hours prematch. Plasma [CK] significantly (p < 0.05) increased 30 minutes postmatch with a peak occurring 24 hours postmatch and remained elevated above 24 hours prematch for at least 120 hours postmatch. There were significant (p < 0.05) correlations between the increase in [CK] and reduction in PRFD 30 minutes postmatch and 24 hours postmatch. The [sCort] was significantly (p < 0.05) correlated with the reduction in PF 30 minutes postmatch. Results demonstrate that neuromuscular function is compromised for up to 48 hours after match play. Elevated [CK] despite 120-hour recovery indicate that damage to muscle tissue after Rugby League match play may persist for at least 5 days postmatch. Despite the prolonged presence of elevated [CK] postmatch, strength training 48 hours postmatch may have resulted in a compensatory increase in PRFD supporting the inclusion of strength training during the short-term postmatch recovery period.

fMRI Randomized Study of Mental and Motor Task Performance and Cortisol Levels to Potentiate Cortisol as a New Diagnostic Biomarker

“…It would seem that cortisol works in two ways: for mental tasks, the demand for cortisol is high but recruitment of brain regions is lower than for physical tasks where the demands on cortisol levels are lower, consistent with elite athletes where cortisol activity is lowered with more training and possibly, more brain regions are recruited with an increase in skills set [34][35][36]. Averaging brain scan results across participants revealed that overall, recruitment of brain region activity is slightly greater than in the physical condition.…”

Treinamento físico pré-competitivo e marcadores de desempenho, estresse e recuperação em jovens atletas de voleibol

“…Monitoring training loads is necessary since the balance between training load and recovery is a determinant factor to obtain positive adaptations to training 9 . Studies have shown a decline in countermovement vertical jump (CMJ) performance after basketball training sessions 10 , after cumulative sessions of overload rugby training with limited recovery 11 , after a rugby game 12 , and after a period of rugby competitions 13 . The loss of muscle function observed after these exhaustive exercises is related to metabolic fatigue and the magnitude of exercise-induced muscle injury 7,14 .…”

Understanding the Fatigue-Recovery Cycle in Team Sport Athletes

“…Measures of neuromuscular function have commonly been used to examine the fatigue response following team sport activities and have been suggested to be reliable indicators of low-frequency fatigue [7,8]. Neuromuscular function has been assessed using jumping protocols, sprinting performance, and isokinetic and isointertial dynamometry.…”

“…Blood and salivary markers have been used to examine the possible mechanisms associated with neuromuscular and perceptual fatigue following team sport competition [7,14,16]. Although testing samples can be expensive, changes in biochemical, hormonal and immunological measures can be easily assessed around daily training activities with non-invasive blood capillary samples and salivary swabs.…”

“…Measures such as creatine kinase, salivary cortisol and testosterone concentrations, plasma glutamine and salivary immunoglobulin A are commonly cited in the literature as markers used to examine athletes health status and response to intensive training and competition [8,18]. However, researchers have found poor temporal relationships with biochemical markers and neuromuscular function following competition and it is yet to be determined if a single biochemical, hormonal or immunological measure can be used to detect non-functional overreaching or overtraining in athletes [7,18]. Further, some biochemical measures such as creatine kinase have been shown to have high day-to-day variability questioning whether these measures can be used to examine changes in an athlete's health status or fatigue-recovery cycle [8].…”