Prediction of performance on two stretcher-carry tasks

Area of Science:

• Occupational Health
• Sports Science
• Human Performance

Background:

• Effective pre-placement screening is crucial for matching individuals to physically demanding jobs.
• Tests must accurately reflect specific job tasks to predict performance and prevent injuries.

Purpose of the Study:

• To evaluate the relationship between various strength measures, fitness scores, and physical descriptors with performance on stretcher-carry tasks.
• To identify key predictors for both repeated short-distance and continuous long-distance stretcher carries.

Main Methods:

• Twelve men and 11 women performed two stretcher-carry tasks (repeated short-distance, continuous long-distance) with and without a harness.
• Seven strength measures, three Army Physical Fitness Test (APFT) scores, and three physical descriptors were assessed.
• Pearson correlations and forward stepwise multiple regression analyses were employed.

Main Results:

• Two-mile run time and handgrip strength were significant predictors for repeated short-distance carries (r2=0.79 for hand-carry, r2=0.75 for harness-carry).
• Grip strength characteristics differed in predictive value: sudden maximal contraction for hand-carry, sustained maximal contraction for harness-carry.
• Sustained grip strength (6-second) was the primary predictor for continuous hand-carry performance (r2=0.74).

Conclusions:

• Pre-placement strength tests must be job-specific to effectively predict performance in physically demanding roles.
• Different aspects of grip strength and endurance are critical for various carrying tasks.
• Optimizing screening protocols requires direct correlation with the physical demands of the target occupation.