The time course of the effects of constant-angle and constant-torque stretching on the muscle-tendon unit.
The purpose of the present study was to examine the time course of passive range of motion (PROM), passive torque (PASTQ), and musculo-tendinous stiffness (MTS) responses during constant-angle (CA) and constant-torque (CT) stretching of the leg flexors. Eleven healthy men [mean ± standard deviation (SD): age = 21.5 ± 2.3 years] performed 16 30-s bouts of CA and CT stretching of the leg flexors. PROM, PASTQ , and MTS were measured during stretches 1, 2, 4, 8, and 16. For PROM and PASTQ , there were no differences between CA and CT stretching treatments (P > 0.05); however, there were stretch-related differences (P < 0.001). PROM increased following one 30-s bout of stretching (collapsed across CA and CT stretching) with additional increases up to 8 min of stretching. PASTQ decreased following one 30-s bout of stretching (collapsed across CA and CT stretching) and continued to decrease up to 4 min of stretching. In contrast, only the CT stretching treatment resulted in changes to MTS (P < 0.001). MTS decreased after one 30-s bout of CT stretching, with subsequent decreases in MTS up to 6 min of stretching. These results suggested that CT stretching may be more appropriate than a stretch held at a constant muscle length for decreasing MTS.
Biomechanics Laboratory, Department of Health, Sport and Exercise Sciences, University of Kansas, Lawrence, Kansas, USA.
T J
TJ
Herda
P B
PB
Costa
A A
AA
Walter
E D
ED
Ryan
J T
JT
Cramer
D004576:Electromyography; D006621:Hip Joint / Q000502:physiology*; D006801:Humans; D008297:Male; D052580:Muscle Stretching Exercises; D018482:Muscle, Skeletal / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology*; D013710:Tendons / Q000502:physiology*; D013997:Time Factors; D019415:Torque; D055815:Young Adult