The effect of exercise-induced muscle damage on perceived exertion and cycling endurance performance

Abstract

This study evaluated the effects of exercise-induced muscle damage (EIMD) on fixed-load cycling and 5-min time-trial performance. Seven recreational athletes performed two submaximal fixed-load exercise bouts followed by a 5-min time-trial before, 48 and 168 h following 100 counter-movement jumps. Measurements of V(O)(2) heart rate, RER and blood lactate concentration remained unchanged during the fixed-load bouts following jumping exercise. However, VE and VE/VO2 increased (P < 0.05) at 48 h. RPE values were higher at 48 h as were the ratio of RPE:HR and RPE:VO2 (P < 0.05). In the time-trial, mean VO2 peak power output, mean power output, distance covered and post exercise blood lactate were lower at 48 h (P < 0.05). RPE remained unchanged between trials. These findings indicate that the ventilatory equivalent for oxygen and perceived exertion at submaximal work rates are increased 48 h following eccentric exercise. Furthermore, EIMD increases perceived exertion and impairs performance during a 5-min all-out effort.

Lower-volume muscle-damaging exercise protects against high-volume muscle-damaging exercise and the detrimental effects on endurance performance

“…This corresponds with previous studies, whereby distance covered during cycling (Burt and Twist 2011;Twist and Eston 2009) and running (Marcora and Bosio 2007) time-trials is decreased by 4 -6% as a result of EIMD. However, this is the first study to demonstrate that the detrimental effects of EIMD on running time-trial performance are less prevalent after a second bout.…”

“…The elevated ˙V E response could also explain the concomitant increase in RPE during fixed-intensity running. Feelings of breathlessness might have provided a central cue to inform RPE, whilst it is also possible that muscle soreness experienced in the knee extensors provided a peripheral cue to alter the sense of effort (Davies et al 2009;Jameson and Ring 2000;Twist and Eston 2009). This is the first study to confirm that EMG amplitude is increased during fixed-intensity running after EIMD.…”

“…The VAS comprised written cues from left (no muscle soreness) to right (muscles too sore to move), which corresponded to a number (0-10 unseen by the participant) on the reverse side. This scale has been used successfully in previous research (Twist & Eston 2009) and has been established as a valid and reliable measurement tool of soreness (Price et al 1983). …”

“…Indeed, decreases in distance covered (~6%), average power output (~12%) and oxygen cost (~11%) have been observed during cycling and running timetrials performed after EIMD (Burt and Twist 2011;Marcora and Bosio 2007;Twist and Eston 2009). The mechanims posited to explain the decrement in time-trial performance include an altered sense of effort, a reduction in neural drive and an increased production of inflammatory cytokines (Burt and Twist 2011;Marcora and Bosio 2007;Twist and Eston 2009). However, whether this reduction in time-trial performance is still evident after a repeated bout of EIMD remains unknown.…”

The effect of glycogen reduction on cardiorespiratory and metabolic responses during downhill running

“…In agreement, increased / CO and decreased / O have been shown for incremental cycling exercise with depleted glycogen (Hughes et al 1982 ). Elsewhere, increased / O has been associated with greater effort perception when exercising with muscle damage (Twist and Eston 2009 Our protocol featured a recovery period between the glycogen reduction cycling and the downhill run of ~10 h. This interval allowed time for other confounding physiological disturbances, aside from glycogen reduction, associated with prolonged exercise (e.g., body temperature and hormonal alterations) to pass. Thus, for the downhill run we are confident that the effects of lowered muscle glycogen, and not the effects of other exercise induced perturbations, were being observed.…”