STATIC STRETCHING REDUCES ISOKINETIC PEAK TORQUE AND EMG AMPLITUDE
Cramer, J. T., Housh, T. J., Johnson, G. O., Miller, J. M., & Coburn, J. W. (2003). The acute effects of static stretching on peak torque and EMG of the stretched and unstretched (contralateral) vastus lateralis muscles. Medicine and Science in Sports and Exercise, 35(5), Supplement abstract 2128.
Females (N = 14) performed separate maximal, concentric isokinetic leg extensions of the dominant and non-dominant (contralateral) limbs on a CBEX ergometer at 60 and 240 deg/sec. Peak torque (PT) and EMG amplitude (EMG) were measured for the vastus lateralis muscles. Following baseline measures, the dominant leg was stretched for 20 minutes using one unassisted and three assisted static stretching exercises. After 10 minutes post-stretching, measures were repeated.
There were no pre- and post-stretch interaction factors. However, stretching caused peak torque and EMG amplitude to be reduced in both the dominant and non-dominant (unstretched) limbs. This suggests there is some neural component in stretching that transfers bilaterally to the unstretched limb.
Implication. Static stretching reduces peak torque and EMG amplitude in both the exercised dominant leg and the unstretched non-dominant limb.