Effect of diathermy on muscle temperature, electromyography, and mechanomyography.
This study examined the effects of pulsed shortwave diathermy on intramuscular temperature, surface electromyography (EMG), and mechanomyography (MMG) of the vastus lateralis. Thirty-five men were assigned to diathermy (n = 13), sham-diathermy (n = 12), or control (n = 10) groups. Each subject performed isometric maximal voluntary contractions (MVCs) and incremental ramp contractions (10%-90% MVC) before and after treatment. Torque, intramuscular temperature, EMG, and MMG were recorded. Temperature for the diathermy group increased (P <or= 0.05). MMG amplitude and instantaneous mean frequency (IMF) increased (P <or= 0.05) during the MVCs with the greatest increases observed for the diathermy group. During ramp contractions, MMG amplitude and IMF increased at all percentages of MVC (10%-90%) for the diathermy group only (P <or= 0.05). There were no changes in MVC torque, EMG amplitude, or IMF. Diathermy treatments may decrease musculotendinous stiffness, but not absolute strength or motor control strategies that influence force production.
Mitchell
Sarah M
SM
Athletic Training Education, Texas A&M University - Commerce, Commerce, Texas, USA.
Trowbridge
Cynthia A
CA
Fincher
A Louise
AL
Cramer
Joel T
JT
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001696:Biomechanical Phenomena; D001831:Body Temperature / Q000528:radiation effects*; D003972:Diathermy / Q000379:methods*; D004558:Electric Stimulation / Q000379:methods; D004576:Electromyography; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000502:physiology / Q000528:radiation effects; D018482:Muscle, Skeletal / Q000502:physiology* / Q000528:radiation effects*; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted; D013314:Stress, Mechanical