Time Restricted Feeding Reduces Inflammation and Cortisol Response to a Firegrounds Test in Professional Firefighters

Objective: Firefighters are at a heightened risk for developing cardiovascular disease. The purpose of this study was to determine if time restricted feeding (TRF) can improve the stress/inflammatory response to a simulated firegrounds test (FGT) in professional firefighters. Methods: Thirteen firefighters participated in an 8-week TRF intervention (14:10 [fasting:feeding]) protocol and completed a FGT before and after the intervention. Blood lactate, heart rate, salivary C-reactive protein (CRP), interleukin-6 (IL-6), interleukin 1-β (IL-1β), and cortisol were measured pre and post FGT. Results: Following TRF, the salivary cortisol response to the FGT was significantly ( P < 0.05) reduced. Salivary IL-6 and IL-1β were also significantly lower, and CRP was higher following the intervention. Conclusions: These findings demonstrate lower inflammation and reduced stress response to FGT following TRF and may suggest implications in terms of cardiometabolic benefits for firefighters.