"F!reF!ghterF!t": Lifestyle Coaching Interventions for Obese Firefighters (FireFit) (FireFit)

"F!reF!ghterF!t": A Randomized Controlled Trial of Lifestyle Coaching Interventions for Obese Firefighters

Our goal is to explore the effectiveness of 9- month lifestyle medicine based coaching intervention (individual and group coaching) versus control (usual care/ written health instructions). The primary study outcomes will be mean changes in body composition metrics . Secondary outcomes will be the prevalence of metabolic abnormities, progression/regression of Metabolic Syndrome, push-up & sit/stand capacity, self-reported physical activity, and quality of life/diet/sleep measures.

Study Overview

• Status: Not yet recruiting
• Conditions: Obesity and Obesity-related Medical Conditions
• Intervention / Treatment: Behavioral: Lifestyle Coaching

Detailed Description

RATIONALE/GOALS: Obesity is a major health hazard in the US fire service. It contributes to excess cancer, cardiovascular disease and behavioral health issues. Obesity is negatively associated with 12/13 health priorities identified by the National Fallen Firefighter Foundation. Mitigating obesity is crucial to the fire service's goals of reducing chronic diseases and their adverse economic/operational impacts.

METHODS: At least 75 male firefighters self-reporting a body mass index (BMI) of >/= 30 kg/m2 AND interest in weight loss will complete a baseline health assessment including: lifestyle scores, body composition, metabolic/hormonal indices, physical fitness, and behavioral health screens, until 50 eligible firefighters have been consented and enrolled. After the initial clinical evaluation, 50 eligible firefighters will be randomized into the two study groups (about 25 firefighters to each arm): 1. General Health Instructions (CONTROL) and 2. Individual & Group Lifestyle Coaching based on the six pillars of Lifestyle Medicine & Full Plate Living. Participants will repeat the all health/fitness measures at 3-, 6- and 9-months post study entry. The two treatment groups will be compared on an intention to treat basis.

ANTICIPATED OUTCOMES: Compared to CONTROL, firefighters receiving the Lifestyle Coaching Intervention should achieve significantly greater improvements in body composition, metabolic & other health measures, as well as adopt healthy lifestyle behaviors.

• Study Type: Interventional
• Enrollment (Estimated): 50
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Massachusetts
    • Sommerville, Massachusetts, United States, 02145
      • Cambridge Health Alliance
      • Contact: Patricia Lenehan; Phone Number: 617-665-1580; Email: elidoriki@challiance.org
      • Principal Investigator: Stefanos N Kales, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Male firefighters aged 18-60 years
• Currently active as volunteer or career firefighters
• Body mass index (BMI) ≥30 kg/m² based on self-reported height and weight
• Express interest in participating in a clinical study aimed at improving body composition (weight loss), metabolic status, and quality of life
• Residing and/or working in Massachusetts, Rhode Island, or Southern New Hampshire (Boston metro area)

Exclusion Criteria:

• Female sex*
• BMI <30 kg/m² based on self-reported height and weight
• Active psychosis
• History or diagnosis (during the RCT) of any of the following:

Major cardiovascular disease event (e.g., myocardial infarction, cardiac arrest, cerebrovascular accident) Cancer (excluding non-melanoma skin cancer) Abnormal liver function (aminotransferase, bilirubin, or alkaline phosphatase ≥3× the upper limit of normal) Renal dysfunction (estimated glomerular filtration rate ≤30 mL/min/1.73 m²)

• Current or recent (within 6 months) use of testosterone treatment or anti-obesity/obesogenic medications

• Unwillingness to adhere to potential intervention assignments

  • Because this is an exploratory study, the number of subjects is limited, and men make up roughly 85% of the US fire service, the current proposal is limited to men. In future studies, we will include women firefighters.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Control/ General Written Health Instructions; Participants will receive standard lifestyle recommendations, consisting of two pages of written information summarized from the American Heart Association's 'Healthy for Good' webpages for the general public. These will include guidance on healthy diets, physical activity, healthy sleep, stress reduction, and avoiding tobacco, excess alcohol, and other harmful substances.
Active Comparator: Individual & Group Lifestyle Medicine-based Coaching; This group will receive personal and group coaching sessions based on the six pillars of lifestyle medicine: 1) a plant- predominant eating pattern (consistent with the AIH "Full Plate Living" program); 2) physical movement; 3) restorative sleep; 4) management of stress; 5) avoidance of risky substances; and 6) positive social connections. Target goals for the participants assigned to Lifestyle Coaching will include the following: improving diet quality together with moderate caloric restriction; engaging in more physical activity with a goal of 150 minutes or more per week of at least moderate intensity (e.g. brisk walking); getting 7-8 hours of sleep nightly when possible and using short naps when work or other conditions interfere with getting at least 7 hours of sleep; increasing resilience and using positive social/family connections to manage/decrease stress.	Behavioral: Lifestyle Coaching; The schedule for the individual and group coaching sessions is summarized below: Individual Coaching: Six one-on-one online sessions with a trained dietician, starting with an initial 30-minute session at baseline, followed by sessions at one month and then every other month.; Group Coaching: 60-minute group online sessions with up to 15 participants per group. Group sessions schedule: there will be a total of 13 group sessions. They will meet once a week for the first 4 weeks, twice monthly for the next 8 weeks of follow-up, and then monthly for the remaining follow-up until the 13th session.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean change in body mass index	Body Mass Index (kg/m-squared)	From the start of the intervention to its conclusion at nine months.
Mean change in body fat	Body fat percentage as measured by bioelectrical impedance	From the start of the intervention to its conclusion at nine months.
Mean change in waist circumference	Waist circumference (cm)	From the start of the intervention to its conclusion at nine months.
Mean change in waist/hip ratio	Waist/hip ratio (waist circumference (cm) divided by hip circumference (cm)	From the start of the intervention to its conclusion at nine months.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Prevalence of Metabolic Syndrome	Number (%) of participants with 3 or more metabolic syndrome components	From the start of the intervention to its conclusion at nine months.
Push-up capacity	1-minute push-up capacity	From the start of the intervention to its conclusion at nine months.
Sit/stand capacity	1-munute sit to stand completions	From the start of the intervention to its conclusion at nine months.
Self-reported Healthy Lifestyle Score	Score based on self-reported health behaviors from a standardized survey tool with validated component metrics	From the start of the intervention to its conclusion at nine months.
Self-reported quality of life	Score based on the validated Short Form-12 Health Survey (SF-12). The SF-12 generates two summary scores: the Physical Component Summary (PCS) and the Mental Component Summary (MCS), each ranging from 0 to 100. Higher scores indicate better health-related quality of life.	From the start of the intervention to its conclusion at nine months.

Collaborators and Investigators

• Sponsor: Cambridge Health Alliance
• Collaborators: Ardmore Institute of Health

Study record dates

Study Major Dates

• Study Start (Estimated): April 21, 2026
• Primary Completion (Estimated): October 31, 2026
• Study Completion (Estimated): December 1, 2026

Study Registration Dates

• First Submitted: March 12, 2025
• First Submitted That Met QC Criteria: March 20, 2025
• First Posted (Actual): March 24, 2025

Study Record Updates

• Last Update Posted (Actual): February 23, 2026
• Last Update Submitted That Met QC Criteria: February 19, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: quality of life; obesity; mental health; healthy lifestyle; metabolic syndrome; diabetes mellitus; physical fitness; lifestyle medicine; coaching; firefighters
• Additional Relevant MeSH Terms: Endocrine System Diseases; Nutrition Disorders; Metabolic Diseases; Overnutrition; Body Weight; Glucose Metabolism Disorders; Insulin Resistance; Hyperinsulinism; Overweight; Pathological Conditions, Signs and Symptoms; Behavior; Nutritional and Metabolic Diseases; Signs and Symptoms; Personal Satisfaction; Obesity; Metabolic Syndrome; Diabetes Mellitus; Psychological Well-Being
• Other Study ID Numbers: CHA-IRB-23-24-340

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: IPD will not be shared due to privacy concerns and data-use restrictions

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No