Hip Abductor Power and Velocity: Reliability and Association With Physical Function

Area of Science:

• Biomechanics
• Exercise Physiology
• Kinesiology

Background:

• Muscle power, the ability to produce torque rapidly, is crucial for physical function and performance.
• Hip abductor capacity for torque and velocity is vital for various human activities.
• Reliable assessment of hip abduction is necessary to understand its role in physical function.

Purpose of the Study:

• To assess the intersession reliability of hip abductor maximal torque and submaximal power and velocity using pneumatic resistance in young adults.
• To investigate the relationship between hip abductor maximal torque, submaximal power, and velocity with clinical assessments of lower-extremity strength and power.

Main Methods:

• 24 young adults participated in two laboratory visits.
• Participants performed 1-repetition maximum (1RM) and submaximal hip abduction tests (40%, 60%, 70% of 1RM) on a pneumatic resistance machine.
• Clinical tests included the 30-second chair stand test (30CST) and stair climb power test.

Main Results:

• One-repetition maximum torque and submaximal power and velocity exhibited excellent intersession reliability (ICC ≥ 0.943).
• Absolute reliability ranged from 13.5% to 28.3%.
• Hip abduction velocity positively correlated with 30CST performance at 60% (r = 0.416) and 70% of 1RM (r = 0.442).

Conclusions:

• Pneumatic resistance provides a reliable method for assessing hip abductor 1RM torque, submaximal power, and velocity.
• Hip abduction velocity is potentially important for the performance of functional tasks like the 30-second chair stand test.