Longitudinal Stability of The Handgrip Strength Measurements in University Students

Area of Science:

• Sports Medicine
• Biometrics
• Human Physiology

Background:

• Handgrip strength is a key indicator of physical fitness and future health.
• Annual measurement is standard, but longitudinal consistency is not well-studied.

Purpose of the Study:

• To assess the reliability of annual handgrip strength measurements in university students.
• To determine how measurement consistency changes over 1, 2, and 3-year intervals.

Main Methods:

• Longitudinal study of 3649 university students (2769 males, 880 females) over four years.
• Analysis of absolute errors and percentage coefficient of variation (%CV) across test-retest intervals.
• Comparison of reliability between sexes and between digital and analog devices.

Main Results:

• 1-year reproducibility was significantly better than 2-year and 3-year intervals.
• Minimal difference values were 7.70 kg (1-year), 8.33 kg (2-year), and 8.35 kg (3-year).
• Digital devices showed better reliability than analog; reliability varied between sexes depending on the metric (%CV vs. absolute error).

Conclusions:

• Annual handgrip strength measurements demonstrate decreasing reliability over longer intervals.
• A change of approximately 20% is recommended to confidently indicate a true change in young adults.
• Findings aid in interpreting the consistency of annual handgrip strength assessments.