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Updated: Jul 13, 2026
Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations
Published on: May 1, 2018
Correlations among flexibility, stiffness, strength and muscle ultrasound parameters in older males afflicted with
Wirasinee Srijunto1, Juntip Namsawang1, Sirawee Chaovalit2
1Department of Physical Therapy, Allied Health Sciences Faculty, Burapha University, Chonburi, Thailand.
Introduction:
Age-induced inflexibility may lead to significant mobility impairments and declines in well-being. However, the relationship between the structural and mechanical properties of soft tissue and joint extensibility remains unclear. This study aimed to investigate the correlation between flexibility, muscle tendon unit (MTU) stiffness, muscle ultrasound characteristics, muscle strength, and hamstring flexibility prediction in older males with hamstring inflexibility.
Methods:
A hundred retired old males (mean age: 67.2 ± 4.9 years) participated in this investigation. Muscle ultrasound, flexibility, MTU stiffness, and knee flexors strength were measured in a single visit.
Results:
The results revealed a modest correlation between straight leg raise (SLR) and biceps femoris fascicle length (FL) elongation (r = 0.222), MTU stiffness (r = -0.401), and eccentric strength (r = 0.219) (all p < 0.05). MTU stiffness, eccentric strength, and FL elongation collectively explained 24.8% of the variance in SLR prediction, while deep fascia thickness predicted MTU stiffness with a variance of 6.4%.
Conclusion:
In summary, increased SLR was associated with lower MTU stiffness, lengthened FL, and higher eccentric strength. SLR was primarily predicted by MTU stiffness, with lesser contributions from FL elongation and knee flexor eccentric strength in older males experiencing hamstring tightness.
