Effects of time-efficient occupational exercise on cardiorespiratory fitness in firefighters

Objective: For a cohort of operational firefighters, we assessed the effects of workplace-based high-intensity interval training (HIIT) on cardiorespiratory fitness. Methods: Fifteen firefighters performed HIIT or moderate-intensity continuous training for 4 weeks. Outcomes were peak oxygen uptake, time trial performance, and affective (pleasure/displeasure) responses to exercise. Results: There was an increase in peak oxygen uptake for both conditions, although this did not reach statistical significance (P = 0.06, η ² = 0.26) and time trial performance improved for both groups (2%, P < 0.01, η ² = 0.51). Affective responses were more favorable for HIIT, but both conditions avoided excessive sensations of displeasure. Conclusion: Results suggest that workplace-based HIIT improved fitness and performance to a similar magnitude to moderate-intensity continuous training while avoiding overly negative affective responses and could improve occupational health of firefighters, despite reduced time commitment.