In:
American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, American Physiological Society, Vol. 317, No. 2 ( 2019-08-01), p. R346-R354
Kurzfassung:
Exhaustive single-leg exercise has been suggested to reduce time to task failure (T lim ) during subsequent exercise in the contralateral leg by exacerbating central fatigue development. We investigated the influence of acetaminophen (ACT), an analgesic that may blunt central fatigue development, on T lim during single-leg exercise completed with and without prior fatiguing exercise of the contralateral leg. Fourteen recreationally active men performed single-leg severe-intensity knee-extensor exercise to T lim on the left (Leg 1 ) and right (Leg 2 ) legs without prior contralateral fatigue and on Leg 2 immediately following Leg 1 (Leg 2-CONTRA ). The tests were completed following ingestion of 1-g ACT or maltodextrin [placebo (PL)] capsules. Intramuscular phosphorus-containing metabolites and substrates and muscle activation were assessed using 31 P-MRS and electromyography, respectively. T lim was not different between Leg 1ACT and Leg 1PL conditions (402 ± 101 vs. 390 ± 106 s, P = 0.11). There was also no difference in T lim between Leg 2ACT-CONTRA and Leg 2PL-CONTRA (324 ± 85 vs. 311 ± 92 s, P = 0.10), but T lim was shorter in Leg 2ACT-CONTRA and Leg 2PL-CONTRA than in Leg 2CON (385 ± 104 s, both P 〈 0.05). There were no differences in intramuscular phosphorus-containing metabolites and substrates or muscle activation between Leg 1ACT and Leg 1PL and between Leg 2ACT-CONTRA and Leg 2PL-CONTRA (all P 〉 0.05). These findings suggest that levels of metabolic perturbation and muscle activation at T lim are not different during single-leg severe-intensity knee-extensor exercise completed with or without prior fatiguing exercise of the contralateral leg. Despite contralateral fatigue, ACT ingestion did not alter neuromuscular responses, muscle metabolites, or exercise performance.
Materialart:
Online-Ressource
ISSN:
0363-6119
,
1522-1490
DOI:
10.1152/ajpregu.00084.2019
Sprache:
Englisch
Verlag:
American Physiological Society
Publikationsdatum:
2019
ZDB Id:
1477297-8
SSG:
12
