Exercise associated muscle cramping (EAMC) is a poorly understood problem that is neuromuscular in origin. Ingestion of TRP channel agonists has been efficacious in attenuating electrically-induced muscle cramps.
Purpose
To examine the effect of TRP agonist ingestion on voluntarily-induced EAMC and motor function.
Methods
Study 1: 39 subjects completed 2 trials after ingesting TRP agonist-containing active treatment (A), or vehicle (V) control. Cramping in the triceps surae was induced via voluntary isometric contraction. Study 2: After ingesting A or V, 31 subjects performed kinematic and psychomotor tests of manual dexterity.
Results
A increased pre-cramp contraction duration (A:36.9±4.1, V:27.8±3.1 s), decreased cramp EMG area under the curve (A:37.3±7.7, V:77.2±17.7 %EMGmax•s), increased contraction force to produce the cramp (A:13.8±1.8, V:9.9±1.6 kg), and decreased post-cramp soreness (A:4.1±0.3, V:4.7±0.3 a.u.). Kinematic and psychomotor tests were not affected.
Discussion
TRP agonist ingestion attenuated EAMC characteristics without affecting motor function.