Jackson Strength Evaluation System for Isometric Force and Functional Capacity Testing

Jackson Strength Evaluation System (Lafayette Instrument Model 32728) for Objective Isometric Strength and Functional Capacity Testing

In occupational health, industrial functional capacity evaluations (FCE), physical therapy clinics, and sports medicine research, evaluating a patient’s or job applicant’s maximum physical lifting and pulling capabilities requires rigorous, standardized, and legally defensible instrumentation. Subjective strength assessments or unstructured free-weight testing often introduce significant inter-tester variability and injury risks. Developed originally by Dr. Andrew Jackson at the University of Houston, the Jackson Strength Evaluation System directly addresses these diagnostic challenges by providing a precise, electronic load-cell-based testing platform designed specifically to measure static isometric strength across major muscle groups, meeting recognized National Institute of Occupational Safety and Health (NIOSH) lifting protocols.

Designed explicitly for physical therapists, occupational health physicians, industrial evaluators, and ergonomic specialists, the system combines a heavy-duty steel base platform, a robust chain-and-lift-bar apparatus, a high-capacity 1000 lb electronic load cell, and a handheld tablet running specialized data acquisition software (LEval application). The system measures peak force, average force, and force-over-time curves during controlled isometric lifts and pulls without requiring active movement of the load, drastically minimizing joint strain while capturing maximum voluntary contraction data. From assessing upper-arm and shoulder lifting capacity to executing full torso and back strength evaluations, the unit provides reliable metrics to determine safe return-to-work parameters and pre-employment physical qualifications.

Key Benefits:

• High-Capacity 1000 lb Electronic Load Cell: Accurately and reliably measures high-force isometric outputs during maximum voluntary contraction testing for heavy-duty industrial and clinical evaluations.
• NIOSH & Standardized Protocol Compliance: Engineered specifically to satisfy established Jackson lift, pull, and torso strength protocols and the lifting task criteria outlined by NIOSH.
• Tablet-Based LEval Software Interface: Handheld digital display provides real-time tracking of peak force, average force, and force-over-time graphs with automated data storage.
• Safe Isometric Testing Methodology: Measures static force generation without dynamic load displacement, significantly reducing injury risks for recovering patients during maximal effort trials.
• Multi-Position Functional Testing: Accommodates interchangeable configurations to evaluate grip, arm, shoulder, torso, and back strength using a secure chain and bar system.
• Objective Return-to-Work Data: Generates quantitative documentation essential for occupational health screening, functional capacity evaluations (FCE), and job-fit placement decisions.
• Portable & Professional Construction: Compact, modular framework allows clinicians and industrial evaluators to transport and set up the testing system easily across different facility environments.

Specifications:

• Load Cell Capacity: Up to 1000 lbs (453 kg) electronic load cell precision sensor
• Hardware Components: Steel platform base, adjustable chain system, lift/pull bar, and electronic load cell assembly
• Data Display & Capture: Handheld Nexus/Android tablet with pre-loaded LEval data collection software
• Measured Parameters: Peak force, average force, time-to-peak, and continuous force-over-time curves
• Testing Protocols Supported: Isometric arm lift, shoulder lift, torso pull, back strength, and NIOSH-compliant lifting evaluations
• Power Requirements: Rechargeable tablet battery and low-voltage electronic load cell power supply
• Primary Applications: Occupational health screening, industrial functional capacity evaluations (FCE), physical therapy rehabilitation, and ergonomic job-matching