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Updated: Apr 15, 2026

A Real-World High-Intensity Interval Training Protocol for Cardiorespiratory Fitness Improvement
Published on: February 22, 2022
High-intensity Fitness Training Among a National Sample of Male Career Firefighters
Sara A Jahnke1, Melissa L Hyder1, Christopher K Haddock1
1Center for Fire, Rescue, and EMS Health Research, Institute for Biobehavioral Health Research, National Development and Research Institutes, Leawood, KS, USA.
Abstract:
Obesity and fitness have been identified as key health concerns among USA firefighters yet little is known about the current habits related to exercise and diet. In particular, high-intensity training (HIT) has gained increasing popularity among this population but limited quantitative data are available about how often it is used and the relationship between HIT and other outcomes. Using survey methodology, the current study evaluated self-reported HIT and diet practice among 625 male firefighters. Almost one-third (32.3%) of participants reported engaging in HIT. Body composition, as measured by waist circumference and percentage body fat, was significantly related to HIT training, with HIT participants being approximately half as likely to be classified as obese using body fat [odds ratio (OR) = 0.52, 95% confidence interval (CI) = 0.34-0.78] or waist circumference (OR = 0.61, 95% CI = 0.37-0.98). Those who engaged in HIT were more than twice as likely as those who did not (OR = 2.24, 95% CI = 1.42-3.55) to meet fitness recommendations. Findings highlight directions for future prevention and intervention efforts.
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