Comprehensive Physical Work Capacity Evaluations for Korean Farmers Assessed in Healthy Volunteers

Abstract

Objective: To establish the lower limits of normative values of the physical work capacity for Korean farmers in healthy working individual. Methods: We developed a comprehensive set of physical work capacity evaluation items that encompass common farming tasks. These items include measurements of trunk flexion/extension angles, strength (hand grip, trunk flexion/extension, leg/ back lifting, and pushing/ pulling), and positional tolerances. We calculated the normative values for the items and defined the normal range in 124 healthy volunteers aged 20–79 years. We calculated the intraclass correlation coefficient (ICC) to validate the test-retest reliability of the measurements protocol. Results: The normal values for each measurement item were as follows: trunk flexion and extension angle (65.3°±11.6° and 29.6°±6.6°), dominant hand grip strength (32.2±10.5 kgf), trunk flexion and extension strength (288.4±119.0 N and 297.3±129.9 N), leg and back lifting strength (452.9±233.5 N and 349.2±166.7 N), pushing and pulling strength (214.7±75.1 N and 221.7±63.3 N), and positional tolerance time (squat: 76.8±9.0 seconds, front: 73.8±7.7 seconds, twist: 82.2±8.8 seconds, upward: 71.9±11.3 seconds). Regarding test-retest reliability, all strength measurements demonstrated excellent absolute agreement (ICC, 0.91–0.96). However, positional tolerance showed poor-to-moderate absolute agreement (ICC, 0.37– 0.58). Conclusion: We conducted measurements of muscle strength and positional tolerance in healthy participants of various ages, focusing on tasks commonly performed by Korean farmers. The outcomes hold significant value as they offer a pertinent instrument for assessing the appropriateness of workers, thereby carrying implications for rehabilitation objectives, legal evaluations, and work capacity assessments within the agricultural domain.