Changes in force and stiffness after static stretching of eccentrically-damaged hamstrings
This study compared responses to static stretching between eccentrically damaged and non-damaged muscles.
Twelve young men performed 60 maximum knee flexor eccentric contractions of one leg, and received a 300-s continuous passive static stretching at tolerable intensity without pain to both knee flexors at 2 and 4 days after the eccentric exercise. Range of motion (ROM) and passive stiffness during knee extension, passive torque at onset of pain (PT), maximum voluntary isometric (MVC-ISO) and isokinetic concentric contraction torque (MVC-CON), and visual analogue scale (VAS) for muscle soreness were measured before, immediately after, 60 min, 2 and 4 days after exercise as well as before, immediately after, 20 and 60 min after the stretching. Changes in these variables after eccentric exercise and stretching were compared between limbs.
The eccentric exercise decreased MVC-ISO, MVC-CON, ROM and PT, and increased passive stiffness and VAS (p < 0.05), suggesting that muscle damage was induced to the knee flexors. ROM and PT increased after stretching for both limbs; however, the magnitude of the increase was greater (p < 0.05) for the damaged than non-damaged limb. Passive stiffness decreased for both limbs similarly (4–7 %) at immediately after stretching (p < 0.05). Significant decreases in MVC-ISO torque (7–11 %) after stretching were observed only for the non-damaged limb (p < 0.05), but MVC-CON torque did not change after stretching for both limbs. VAS decreased for the exercised limb after stretching (p < 0.05).
These results suggest that the static stretching at tolerable intensity without pain produced greater positive effects on damaged than non-damaged muscles.
KeywordsStatic stretching Range of motion Passive stiffness Stretching-induced force loss Muscle damage Delayed onset muscle soreness
Analysis of variance
Coefficient of variation
Delayed onset muscle soreness
Intra-class correlation coefficients
- MVC-CON torque
Maximum voluntary concentric contraction torque
- MVC-ISO torque
Maximum voluntary isometric contraction torque
Rate of force development
Root mean square
Range of motion
Static passive torque
Visual analogue scale
This work was supported in part by a grant from A-kit Co., Ltd. and the Public Advertisement Research Project of Nihon Fukushi University.
Conflict of interest
All the authors declare that there is no conflict of interest regarding this article.
- Cramer JT, Beck TW, Housh TJ, Massey LL, Marek SM, Danglemeier S, Purkayastha S, Culbertson JY, Fitz KA, Egan AD (2007) Acute effects of static stretching on characteristics of the isokinetic angle–torque relationship, surface electromyography, and mechanomyography. J Sports Sci 25(6):687–698. doi: 10.1080/02640410600818416 CrossRefPubMedGoogle Scholar
- Magnusson SP, Simonsen EB, Aagaard P, Boesen J, Johannsen F, Kjaer M (1997) Determinants of musculoskeletal flexibility: viscoelastic properties, cross-sectional area, EMG and stretch tolerance. Scand J Med Sci Sports 7(4):195–202. doi: 10.1111/j.1600-0838.1997.tb00139.x CrossRefPubMedGoogle Scholar