Feasibility of a Train-the-Trainer Delivered Exercise Intervention in Firefighters

NCT05287594 | Completed

• 1 other identifier: 21-2522
• Study Type: interventional
• Target: 55
• Locations: 1 country
• Sites: 1

Brief Summary

Purpose: To collect and report feasibility data for conducting a future cluster randomized trial to evaluate the efficacy of a TRAINER delivered integrated exercise program in career firefighters, and to determine intervention fidelity and preliminary effects of a TRAINER delivered integrated exercise program in career firefighters. Participants: 52 career firefighters 18 - 60 years old (40 trainees, 6 trainers, 6 administrators). Procedures (methods): Enrolled fire stations will be randomly assigned (3:2 allocation ratio) to a TRAINER or wait-list control (CON) group, stratified by city, using computer-generated random numbers. All enrolled firefighters will undergo a series of assessments at baseline (week 0) and post-testing (week 7) following the TRAINER delivered 6-week intervention.

Conditions

High Intensity Interval Training; Firefighter

Keywords

Firefighter; Train-the-Trainer; High intensity interval training; Neuromuscular warm-up; Fire and Rescue Personnel

Outcome Measures

Primary Outcomes (4)

• Number of Firefighters and Fire Stations Recruited to the Study (Feasibility)

  To demonstrate the feasibility of an integrated exercise program. Feasibility will be defined as recruitment of 40 firefighters and the number of fire stations (out of 26 potential) to the study within 14 months.

  Within 14 months

• Percentage of Firefighters Retained (Feasibility)

  To demonstrate the feasibility of an integrated exercise program. Retention will be determined from the percentage of firefighters retained at post-testing. Retention of 80% or higher will be considered good feasibility.

  Week 7 (post-intervention)

• Percentage of Sessions Attended (Feasibility)

  To demonstrate the feasibility of an integrated exercise program. Adherence will be determined from the percentage of sessions attended out of total (12) sessions. Adherence of 80% or higher will be considered good feasibility.

  Week 7 (post-intervention)

• Qualitative Summaries of Participant Experience in Semi-Structured Interviews (Acceptability)

  Acceptability will be assessed by semi-structured interviews with the firefighters, peer-trainers, and departmental administration (e.g. fire chiefs). Qualitative summaries for intrapersonal, interpersonal, and organizational constructs will be reported.

  Week 7 (post-intervention)

Secondary Outcomes (11)

• Change in cardiorespiratory fitness as measured by VO2 peak during cycle ergometry

  Baseline (i.e., pre-intervention), 7 weeks (i.e., post-intervention)

• Change in body composition as measured by % body fat from a 4-compartment model

  Baseline (i.e., pre-intervention), 7 weeks (i.e., post-intervention)

• Change in explosive muscle strength as measured by dynamometry

  Baseline (i.e., pre-intervention), 7 weeks (i.e., post-intervention)

• Change in low-back muscular endurance as measured by a modified Biering-Sorensen test

  Baseline (i.e., pre-intervention), 7 weeks (i.e., post-intervention)

• Change in balance as measured by a modified star excursion balance test

  Baseline (i.e., pre-intervention), 7 weeks (i.e., post-intervention)

Study Arms (2)

TRAINER

EXPERIMENTAL

The TRAINER group will receive an integrated exercise program, led by a peer-trainer, including a neuromuscular warm-up and high intensity interval training at their respective fire stations 2 times per week for 6 weeks.

Behavioral: Integrated Exercise Program

Waitlist Control

NO INTERVENTION

The waitlist control group will not receive training during the course of the study, but will be offered the opportunity to receive the integrated exercise program after the study ends.

Interventions

Integrated Exercise Program BEHAVIORAL

Neuromuscular warm-up: Each participant will perform a series of dynamic stretches, core stability, balance, and medicine ball exercises. The dynamic stretches include 8 repetitions of 6 stretches targeting the hip and thigh musculature, followed by 3 core stability isometric exercises (curl-up, side bridge, and bird dog). Participants will then perform 2 sets (per leg) of hop-to-stabilization (with a reach) balance exercises, followed by 3 separate medicine ball exercises emphasizing explosive full-body movements. High Intensity Interval Training (HIIT): HIIT will include a series of high intensity exercise bouts on a stationary bike that includes a 1:1 work-to-rest ratio. Training intensity will be determined from the peak power output obtained during the baseline VO2 peak assessment and progressively increased by the number of bouts and intensity. The number of work bouts will increase from 5 to 8 bouts and the intensity will increase from 90 to 110% of peak power output.

Also known as: Neuromuscular warm-up, High intensity interval training, HIIT

TRAINER

Eligibility Criteria

• Age: 18 Years - 60 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Provide informed consent prior to any study procedures are performed
• Medically cleared for fire suppression duties
• A career firefighter from a local department (Carrboro, Chapel Hill, and Durham)

You may not qualify if:

• Highly active firefighters, defined as performing 4 or more days/week of vigorous exercise
• Pregnancy
• Recent injury preventing their participation in the exercise routine
• Involved in an active workers' compensation or personal injury case

Sponsors & Collaborators

• University of North Carolina, Chapel Hill: lead
• National Institute for Occupational Safety and Health (NIOSH/CDC): collaborator

Study Sites (1)

UNC Chapel Hill

Chapel Hill, North Carolina, 27599, United States

Location

MeSH Terms

Interventions

High-Intensity Interval Training

Intervention Hierarchy (Ancestors)

Physical Conditioning, Human; Exercise; Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena

Study Officials

• Eric Ryan, PhD

  UNC Chapel Hill

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Two group design where 40 firefighters are cluster randomized (3:2 ratio) into a TRAINER or waitlist control group. There will be 6 trainers who will lead the TRAINER condition. All participants in the TRAINER group and following the intervention in the waitlist control group will receive the same integrated exercise program, led by a peer-trainer, including a neuromuscular warm-up and high intensity interval training at their respective fire stations 2 times per week for 6 weeks.

Study Record Dates

• First Submitted: March 9, 2022
• First Posted: March 18, 2022
• Study Start: April 1, 2023
• Primary Completion: September 26, 2025
• Study Completion: September 29, 2025
• Last Updated: December 19, 2025

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ANALYTIC CODE
• Time Frame: 9 to 36 months following publication
• Access Criteria: Investigator with IRB, IEC, or REB approval and an executed data use agreement with UNC

Locations

US (1)