Effects of Nordic hamstring exercise combined with glider exercise on hip flexion flexibility and hamstring passive...

Area of Science:

• Sports Medicine
• Exercise Physiology
• Rehabilitation Science

Background:

• Eccentric training is recognized for hamstring injury prevention.
• The specific impact of eccentric hamstring training at long muscle lengths on hamstring flexibility remains under-investigated.

Purpose of the Study:

• To assess the effects of eccentric hamstring training performed at long muscle lengths on hamstring flexibility.
• To evaluate the influence of this training on the passive mechanical properties of the hamstring muscles.

Main Methods:

• A randomized controlled trial involving 34 physically active young adults.
• Intervention group: 6 weeks of eccentric hamstring training at long muscle length.
• Measurements included passive hip flexion range of motion, passive hamstring stiffness, shear modulus, and biceps femoris long head tendon length.

Main Results:

• Significant improvement in maximal passive hip flexion range of motion in the intervention group (+11.2%).
• Significant changes observed in shear modulus in a relaxed position.
• No significant changes in passive hamstring stiffness or biceps femoris long head distal tendon length were noted.

Conclusions:

• Eccentric hamstring training at long muscle lengths leads to substantial increases in hamstring flexibility.
• The observed flexibility gains are likely independent of alterations in passive hamstring stiffness or distal tendon length.