Effect of movement speed on trunk and hip exercise performance

Area of Science:

• Biomechanics
• Exercise Physiology
• Kinesiology

Background:

• The effect of movement speed on trunk exercise technique is not well understood.
• Understanding these effects is crucial for effective exercise prescription and injury prevention.

Purpose of the Study:

• To analyze the influence of movement speed on the kinematics and kinetics of curl-up, sit-up, and leg raising/lowering exercises.
• To investigate how different exercise cadences affect trunk and hip joint range of motion (ROM).

Main Methods:

• Seventeen healthy individuals performed exercises at four different cadences (1 repetition/4s, 1 repetition/2s, 1 repetition/1.5s, 1 repetition/1s).
• 3D photogrammetric analysis using three cameras and force plate data were employed.
• Measurements included cephalo-caudal center of pressure displacement and ROM of six key joints.

Main Results:

• Increased speed in sit-up and curl-up exercises led to greater hip and knee ROM.
• Curl-up exercise showed increased dorsal-lumbar and upper trunk ROM with higher speeds.
• Leg raising/lowering exercises demonstrated decreased pelvic tilt and hip ROM, with increased knee flexion at higher speeds.
• Participants altered technique to maintain cadence during faster exercises.

Conclusions:

• Higher exercise speeds necessitate technique modifications, potentially compromising exercise specificity.
• Exercise professionals should monitor and control technique during high-speed exercises.
• Results suggest categorizing exercise speeds into two distinct groups for prescription based on desired outcomes.