Morgan_ajpregu.00084.2019.pdf (982.78 kB)
Contralateral fatigue during severe-intensity single-leg exercise: influence of acute acetaminophen ingestion
journal contribution
posted on 2019-05-31, 13:53 authored by Paul T. Morgan, Stephen BaileyStephen Bailey, Rhys A. Banks, Jonathan Fulford, Anni Vanhatalo, Andrew M. JonesExhaustive single-leg exercise has been suggested to reduce time to task failure (Tlim) during
subsequent exercise in the contralateral leg by exacerbating central fatigue development. We
investigated the influence of acetaminophen (ACT), an analgesic which may blunt central
fatigue development, on Tlim during single-leg exercise completed both with, and without,
prior fatiguing exercise of the contralateral leg. Fourteen recreationally-active men performed
single-leg, severe-intensity knee extensor exercise to Tlim on the left (Leg1) and right (Leg2)
legs without prior contralateral fatigue, and on Leg2 immediately following Leg1 (Leg2-
CONTRA). The tests were completed following ingestion of 1 g ACT or maltodextrin (placebo)
capsules. Intramuscular phosphorous-containing metabolites and substrates, and muscle
activation, were assessed using 31 P-MRS and electromyography, respectively. Tlim was not
different between the Leg1ACT and Leg1PL conditions (402 ± 101 vs. 390 ± 106 s; P=0.11).
There was also no difference in Tlim between Leg2ACT-CONTRA and Leg2PL-CONTRA (324 ± 85 vs.
311 ± 92 s; P=0.10), but Tlim was shorter in these tests compared to Leg2CON (385 ± 104 s;
both P<0.05). There were no differences in intramuscular phosphorous-containing
metabolites and substrates, or muscle activation, between the Leg1ACT and Leg1PL or the
Leg2ACT-CONTRA and Leg2PL-CONTRA conditions (all P>0.05). These findings suggest that levels
of metabolic perturbation and muscle activation are not different at task failure during single leg severe-intensity knee extensor exercise completed with or without prior fatiguing exercise
of the contralateral leg. Despite the existence of contralateral fatigue, ACT ingestion did not
alter neuromuscular responses or exercise performance.
History
School
- Sport, Exercise and Health Sciences
Published in
American Journal of Physiology - Regulatory Integrative and Comparative PhysiologyVolume
317Issue
2Pages
R346 - R354Citation
MORGAN, P.T. ... et al., 2019. Contralateral fatigue during severe-intensity single-leg exercise: influence of acute acetaminophen ingestion. American Journal of Physiology - Regulatory Integrative and Comparative Physiology, 317 (2), pp.R346-R354.Publisher
American Physiological SocietyVersion
- VoR (Version of Record)
Publisher statement
This is an Open Access Article. It is published by American Physiological Society under the Creative Commons Attribution 4.0 Unported Licence (CC BY). Full details of this licence are available at: http://creativecommons.org/licenses/by/4.0/Acceptance date
2019-05-23Publication date
2019-07-26ISSN
0363-6119Publisher version
Language
- en