Electromyographic, mechanomyographic, and metabolic responses during cycle ergometry at a constant rating of perceived exertion.
Ten subjects performed four 8-min rides (65%-80% peak oxygen consumption) to determine the physical working capacity at the OMNI rating of perceived exertion (RPE) threshold (PWCOMNI). Polynomial regression analyses were used to examine the patterns of responses for surface electromyographic (EMG) amplitude (EMG AMP), EMG mean power frequency (EMG MPF), mechanomyographic (MMG) AMP, and MMG MPF of the vastus lateralis as well as oxygen consumption rate, respiratory exchange ratio (RER), and power output (PO) were examined during a 1-h ride on a cycle ergometer at a constant RPE that corresponded to the PWCOMNI. EMG AMP and MMG MPF tracked the decreases in oxygen consumption rate, RER, and PO, while EMG MPF and MMG AMP tracked RPE. The decreases in EMG AMP and MMG MPF were likely attributable to decreases in motor unit (MU) recruitment and firing rate, while the lack of change in MMG AMP may have resulted from a balance between MU de-recruitment as PO decreased, and an increase in the ability of activated fibers to oscillate. The current findings suggested that during submaximal cycle ergometry at a constant RPE, MU de-recruitment and mechanical changes within the muscle may influence the perception of effort via feedback from group III and IV afferents.
a Department of Nutrition and Health Sciences, Human Performance Laboratory, University of Nebraska-Lincoln, 110 Ruth Leverton Hall, Lincoln, NE 68583-0806, USA.
Kristen C
KC
Cochrane
a Department of Nutrition and Health Sciences, Human Performance Laboratory, University of Nebraska-Lincoln, 110 Ruth Leverton Hall, Lincoln, NE 68583-0806, USA.
Terry J
TJ
Housh
a Department of Nutrition and Health Sciences, Human Performance Laboratory, University of Nebraska-Lincoln, 110 Ruth Leverton Hall, Lincoln, NE 68583-0806, USA.
Nathaniel D M
ND
Jenkins
b Department of Kinesiology and Health Promotion, University of Kentucky, Lexington, KY, USA.
Haley C
HC
Bergstrom
a Department of Nutrition and Health Sciences, Human Performance Laboratory, University of Nebraska-Lincoln, 110 Ruth Leverton Hall, Lincoln, NE 68583-0806, USA.
Cory M
CM
Smith
a Department of Nutrition and Health Sciences, Human Performance Laboratory, University of Nebraska-Lincoln, 110 Ruth Leverton Hall, Lincoln, NE 68583-0806, USA.
Ethan C
EC
Hill
a Department of Nutrition and Health Sciences, Human Performance Laboratory, University of Nebraska-Lincoln, 110 Ruth Leverton Hall, Lincoln, NE 68583-0806, USA.
Glen O
GO
Johnson
a Department of Nutrition and Health Sciences, Human Performance Laboratory, University of Nebraska-Lincoln, 110 Ruth Leverton Hall, Lincoln, NE 68583-0806, USA.
Richard J
RJ
Schmidt
a Department of Nutrition and Health Sciences, Human Performance Laboratory, University of Nebraska-Lincoln, 110 Ruth Leverton Hall, Lincoln, NE 68583-0806, USA.
Joel T
JT
Cramer
D000200:Action Potentials; D000328:Adult; D000344:Afferent Pathways / Q000502:physiology; D001642:Bicycling; D004576:Electromyography; D004734:Energy Metabolism; D015444:Exercise; D005080:Exercise Test; D056228:Feedback, Sensory; D005260:Female; D006801:Humans; D008297:Male; D040542:Mechanotransduction, Cellular; D009119:Muscle Contraction; D018482:Muscle, Skeletal / Q000294:innervation / Q000378:metabolism / Q000502:physiology*; D010101:Oxygen Consumption; D010465:Perception; D005082:Physical Exertion; D011999:Recruitment, Neurophysiological; D056152:Respiratory Rate; D013997:Time Factors; D055815:Young Adult
aerobic evaluation; electromyography; exercise intensity; feedback models; intensité de l’exercice; mechanomyography; modèles de rétroaction; mécanomyographie; électromyographie; évaluation de l’effort aérobie