The STS test and its correlation with common clinical indicators for an Argentinian population sample

Area of Science:

• Biomechanics
• Human Movement Science
• Gerontology

Background:

• The Sit-To-Stand (STS) movement is a fundamental functional task crucial for daily living.
• Understanding the biomechanics of STS power is essential for assessing physical function across the lifespan.
• Existing power equations require validation and revision based on empirical data.

Purpose of the Study:

• To assess Sit-To-Stand (STS) power across diverse age groups.
• To revise the biomechanical basis of current STS power equations.
• To investigate correlations between STS power and other functional strength measures.

Main Methods:

• Cross-sectional study of 159 Argentinian individuals aged 18-90 years.
• Inclusion of 5 repetitions STS test, ultrasonography, handgrip, and leg press tests.
• Application of regression analysis and statistical hypothesis testing for data analysis.

Main Results:

• A strong correlation between average and root mean squared (RMS) power indicates clinical sufficiency of existing mean power equations.
• STS power demonstrated a peak around middle age (approximately 55 years), followed by a decline.
• Peak leg press force and rate of force development exhibited the strongest correlations with STS power.

Conclusions:

• Existing mean power equations for STS are clinically adequate, as inertial effects are minimal.
• STS power is highest in middle age and decreases with advancing years.
• STS power is significantly associated with handgrip strength and leg press performance, but not the echogenicity index, emphasizing the importance of evaluating these indicators distinctly.