Relationships between muscle power output using the stretch-shortening cycle and eccentric maximum strength

Area of Science:

• Biomechanics
• Human Physiology
• Sports Science

Background:

• The stretch-shortening cycle (SSC) enhances muscle power output.
• Understanding the relationship between eccentric strength and SSC performance is crucial for optimizing athletic movements.

Purpose of the Study:

• To investigate the association between eccentric maximum strength and muscle power during elbow flexion using the SSC.
• To determine how eccentric strength influences different measures of SSC power output.

Main Methods:

• Eighteen young adult males performed ballistic elbow flexion under static relaxed and SSC conditions with a constant 2 kg load.
• Muscle power (peak and initial) was calculated from pulling velocity.
• Eccentric maximum strength was measured using a handheld dynamometer.

Main Results:

• Initial power was significantly greater in the SSC condition compared to the static relaxed condition.
• Eccentric maximum strength showed a strong positive correlation (r = 0.70) with peak power in the SSC condition.
• No significant correlation was found between eccentric maximum strength and initial power in either condition.

Conclusions:

• Eccentric maximum strength is a significant determinant of peak power achieved during the SSC.
• The contribution of eccentric maximum strength to the initial power enhancement via SSC potentiation appears to be limited.