Voluntary rate of torque development is impaired after a voluntary versus tetanic conditioning contraction. Issue 2 (12th October 2013)

• Record Type: Journal Article
• Authors: Smith, Cameron B.; Allen, Matti D.; Rice, Charles L.
• Is Part Of: Muscle & nerve. Volume 49:Issue 2(2014:Feb.)
• Page Start: 218
• Page End: 224
• Publication Date: 2013-10-12
• Subjects: Neuromuscular diseases -- Periodicals; Muscles -- Periodicals; Nerves -- Periodicals; 616.74
• DOI: 10.1002/mus.23888
• Languages: English
• ISSNs: 0148-639X

Abstract

<abstract abstract-type="main"> <title>ABSTRACT</title> <p> <italic>Introduction</italic>: Both voluntary and evoked conditioning contractions will potentiate muscle twitch contractile properties. The response of a voluntary contraction to each condition type is not well understood but it may be a more functional model than evoked twitch potentiation. <italic>Methods</italic>: Baseline measurements from tibialis anterior included: maximal isometric twitch torque and rate of torque development (RTD); maximal evoked 50‐H<sc>z</sc> torque; and maximal voluntary ballistic RTD. Potentiation was induced by a 10‐s voluntary or tetanic contraction (∽78% MVC), followed by 2 twitches and 2 ballistic contractions. <italic>Results</italic>: Twitch properties (torque and RTD) were potentiated equally after each conditioning contraction. Ballistic RTD was greater post‐tetanus (390.2 ± 59.3 Nm/s) than post‐voluntary (356.4 ± 69.1 Nm/s), but both were reduced from baseline (422.0 ± 88.9 Nm/s). <italic>Conclusions</italic>: Twitch potentiation was similar between conditioning contraction types, but ballistic RTD was lower after post‐tetanus than post‐voluntary. The results indicate central inhibition or fatigue concurrent with peripheral potentiation. <italic>Muscle Nerve</italic><bold>49</bold>: 218–224, 2014</p> </abstract>