SHIFT-48: Schedule and Health Improvements for Firefighters Transitioning to 48/96

Objective Examine the effects of transitioning from a 24/48 to a 48/96 shift schedule on health and performance in firefighters assigned to a single, suburban station. Methods A longitudinal analysis was conducted over three time points in 11 male firefighters. Measures included VO 2peak , peak power, blood pressure, resting heart rate, lipid profiles, and psychological assessments. Linear mixed-effects models analyzed changes across timepoints. Results Transitioning to the 48/96 schedule was associated with improvements in peak power (+27.1 W, p = 0.042), resting blood pressure (SBP −5.5 mmHg, p = 0.05, DBP −5.8 mmHg, p = 0.04), heart rate (−13.2 bpm. p = 0.03), sleep quality (ISI −2.6, p = 0.03), and alcohol use (AUDIT −1.8, p = 0.02); VO 2peak did not reveal a significant time effect ( p > 0.05). Conclusions Extended inter-shift recovery in a 48/96 schedule may promote cardiovascular recovery and readiness without negative health effects in similar departments.