Changes in forearm muscle stiffness in relation to grip strength

Area of Science:

• Biomechanics
• Musculoskeletal research
• Sports science

Background:

• Grip strength is crucial for upper extremity sports.
• Forearm muscles are closely linked to grip strength.
• Quantitative evaluation of muscle influence on grip strength is needed.

Purpose of the Study:

• To quantitatively evaluate how individual forearm muscles are influenced by grip strength variations.
• To utilize shear wave speed measurements for assessing muscle stiffness.

Main Methods:

• Grip strength was measured using a dynamometer.
• Muscle stiffness was assessed via shear wave elastography to determine shear wave speed.
• Measurements were taken on nine adult men at 0 kg and 5 kg grip strength levels.

Main Results:

• Significant increases in shear wave speed were observed for the flexor digitorum superficialis, flexor carpi ulnaris, and flexor digitorum profundus at 5 kg compared to 0 kg grip strength.
• Quantitative analysis confirmed these three muscles significantly contribute to grip strength.
• P-values ranged from 0.000 to 0.005, with effect sizes (d) ranging from 1.824 to 7.819.

Conclusions:

• Training the flexor digitorum superficialis, flexor carpi ulnaris, and flexor digitorum profundus can enhance grip strength.
• These findings are relevant for athletes in upper limb sports.
• The results also suggest benefits for older adults participating in physical activities.