A theoretical framework for predicting altitude effects on physical employment standard evaluation performance

Physical employment standard (PES) evaluations assess whether personnel meet an occupation's minimum physical requirements, supporting operational readiness. Because altitude lowers aerobic capacity, comparability across testing sites at different elevations may require altitude-specific scoring adjustments for aerobic-dominant components. To encourage future efforts to address this, the purpose of this paper is to propose a framework that uses altitude effects observed in existing empirical research to predict altitude effects on PES evaluation performance. No new empirical data are presented; the framework draws on existing altitude-performance literature. We translate altitude effects to PES evaluation performance using four determinants: duration, intensity relative to critical power (CP), work-recovery structure and expected aerobic contribution. The predictions from the framework are expressed as additional completion time at altitude (Δt) and as altitude-specific equivalent cut-scores for a representative aerobic-dominant component with a 360 s sea-level reference, with 7-10% per 1,000 m sensitivity bands above ~1,500 m provided as continuous options. Because aerobic metabolism takes time to dominate an effort, predicted altitude effects scale with task duration: minimal for efforts under 2 min, moderate at 2.5-5 min, and largest at 7.5-10 min. Intermittent work is incorporated using CP and finite work capacity above CP (W'), with W' reconstitution slowed at altitude so that short bouts with incomplete recovery accumulate fatigue more rapidly than at sea level; full parameter values are reported in the methods. A validation roadmap is outlined that includes within-participant estimation of CP, W', and recovery kinetics at altitude, translation to PES component demands, and prospective comparison of altitude-specific versus fixed cut-scores under defined exposure timeframes. Such a framework is essential to preserve comparability of PES evaluation outcomes across locations, support defensible decisions based on PES evaluation results, and maintain operational readiness when critical tasks must be performed in hypoxic environments.