Tags

Type your tag names separated by a space and hit enter

Elbow flexor fatigue modulates central excitability of the knee extensors.
Appl Physiol Nutr Metab. 2015 Sep; 40(9):924-30.AP

Abstract

The present study investigated the effects of exercise-induced elbow flexor fatigue on voluntary force output, electromyographic (EMG) activity and motoneurone excitability of the nonexercised knee extensor muscles. Eleven participants attended 3 testing sessions: (i) control, (ii) unilateral fatiguing elbow flexion and (iii) bilateral fatiguing elbow flexion (BiFlex). The nonfatigued knee extensor muscles were assessed with thoracic motor evoked potentials (TMEPs), maximal compound muscle action potential (Mmax), knee extensor maximal voluntary contractions (MVCs), and normalized EMG activity before and at 30 s, 3 min, and 5 min postexercise. BiFlex showed significantly lower (Δ = -18%, p = 0.03) vastus lateralis (VL) normalized EMG activity compared with the control session whereas knee extension MVC force did not show any statistical difference between the 3 conditions (p = 0.12). The TMEP·Mmax(-1) ratio measured at the VL showed a significantly higher value (Δ = +46%, p = 0.003) following BiFlex compared with the control condition at 30 s postexercise. The results suggest that the lower VL normalized EMG following BiFlex might have been due to a reduction in supraspinal motor output because spinal motoneuronal responses demonstrated substantially higher value (30 s postexercise) and peripheral excitability (compound muscle action potential) showed no change following BiFelex than control condition.

Authors+Show Affiliations

a School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.a School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.a School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.b School of Exercise and Health Sciences, Edith Cowan University, Perth, Australia.a School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

26300013

Citation

Aboodarda, Saied Jalal, et al. "Elbow Flexor Fatigue Modulates Central Excitability of the Knee Extensors." Applied Physiology, Nutrition, and Metabolism = Physiologie Appliquee, Nutrition Et Metabolisme, vol. 40, no. 9, 2015, pp. 924-30.
Aboodarda SJ, Copithorne DB, Power KE, et al. Elbow flexor fatigue modulates central excitability of the knee extensors. Appl Physiol Nutr Metab. 2015;40(9):924-30.
Aboodarda, S. J., Copithorne, D. B., Power, K. E., Drinkwater, E., & Behm, D. G. (2015). Elbow flexor fatigue modulates central excitability of the knee extensors. Applied Physiology, Nutrition, and Metabolism = Physiologie Appliquee, Nutrition Et Metabolisme, 40(9), 924-30. https://doi.org/10.1139/apnm-2015-0088
Aboodarda SJ, et al. Elbow Flexor Fatigue Modulates Central Excitability of the Knee Extensors. Appl Physiol Nutr Metab. 2015;40(9):924-30. PubMed PMID: 26300013.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Elbow flexor fatigue modulates central excitability of the knee extensors. AU - Aboodarda,Saied Jalal, AU - Copithorne,David B, AU - Power,Kevin E, AU - Drinkwater,Eric, AU - Behm,David G, Y1 - 2015/05/06/ PY - 2015/8/25/entrez PY - 2015/8/25/pubmed PY - 2016/6/9/medline KW - cross-over fatigue KW - excitabilité motoneuronale KW - fatigue croisée KW - fatigue périphérique KW - motoneurone excitability KW - peripheral fatigue KW - volontaire KW - voluntary activation SP - 924 EP - 30 JF - Applied physiology, nutrition, and metabolism = Physiologie appliquee, nutrition et metabolisme JO - Appl Physiol Nutr Metab VL - 40 IS - 9 N2 - The present study investigated the effects of exercise-induced elbow flexor fatigue on voluntary force output, electromyographic (EMG) activity and motoneurone excitability of the nonexercised knee extensor muscles. Eleven participants attended 3 testing sessions: (i) control, (ii) unilateral fatiguing elbow flexion and (iii) bilateral fatiguing elbow flexion (BiFlex). The nonfatigued knee extensor muscles were assessed with thoracic motor evoked potentials (TMEPs), maximal compound muscle action potential (Mmax), knee extensor maximal voluntary contractions (MVCs), and normalized EMG activity before and at 30 s, 3 min, and 5 min postexercise. BiFlex showed significantly lower (Δ = -18%, p = 0.03) vastus lateralis (VL) normalized EMG activity compared with the control session whereas knee extension MVC force did not show any statistical difference between the 3 conditions (p = 0.12). The TMEP·Mmax(-1) ratio measured at the VL showed a significantly higher value (Δ = +46%, p = 0.003) following BiFlex compared with the control condition at 30 s postexercise. The results suggest that the lower VL normalized EMG following BiFlex might have been due to a reduction in supraspinal motor output because spinal motoneuronal responses demonstrated substantially higher value (30 s postexercise) and peripheral excitability (compound muscle action potential) showed no change following BiFelex than control condition. SN - 1715-5320 UR - https://www.unboundmedicine.com/medline/citation/26300013/Elbow_flexor_fatigue_modulates_central_excitability_of_the_knee_extensors_ L2 - https://cdnsciencepub.com/doi/10.1139/apnm-2015-0088?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub=pubmed DB - PRIME DP - Unbound Medicine ER -