High-Protein Meal Replacement Intervention in Overweight and Obese Career Firefighters: A Cluster Randomized Controlled Trial
Amber N. Schmitz, Andrew J. Tweedell, Craig R. Kleinberg, Gena R. Gerstner, Nicholas A. Buoncristiani, Eric D. RyanPurpose:
The purpose of this cluster randomized controlled trial was to examine the effectiveness of a 14-week high-protein meal replacement (MRP) intervention on macronutrient intake, body composition, cardiometabolic health, and stair climb (SC) performance in career firefighters with overweight and obesity, and collect acceptability data to inform implementation efforts.
Methods:
Twenty-six fire stations (51 firefighters; 36.7±7.3yrs; 33.1±4.8kg·m −2 ) were randomized to a MRP or wait-list control (CON) group. The MRP group consumed one shake/day (week 1) and two shakes/day (weeks 2-14) ad libitum. The primary outcome was percent body fat (%BF) measured by dual-energy x-ray absorptiometry, and secondary outcomes included macronutrient intake, body mass (BM), body mass index (BMI), regional fat distribution, resting heart rate (RHR) and blood pressure (BP), blood lipids, a weighted and timed SC task, and HR recovery (HR rec ) following the SC task. Intervention acceptability was assessed in the MRP group. Linear mixed models assessed intervention effects with an alpha level set at 0.05.
Results:
The MRP group improved %BF (-1.0 [-1.9, -0.06];
Conclusions:
The MRP intervention improved macronutrient intake, body composition, and SC HR rec and was well accepted, supporting a practical nutritional strategy to improve health in firefighters with overweight and obesity.