Defining Common Terms

The National Institute for Occupational Safety and Health (NIOSH) broadly describes fatigue as "a feeling of weariness, tiredness, or lack of energy." 

Fatigue encompasses multiple dimensions: burnout, cognitive (associated with tasks and sleep), physical, emotional, and perceived fatigue. Here, we focus on understanding physical fatigue and fatigue management. Recovery can be defined as the restoration of health, measured through fatigue levels, functional capacity, and even mood. All these factors are interrelated with firefighter health, well-being, and performance. 

Different stressors lead to physical fatigue, which can build up over time.

• Short-term fatigue comes from physical exhaustion due to stressors, such as insufficient sleep, physical exertion, poor nutrition or hydration, and environmental conditions over hours and days.
  • Acute fatigue can often be improved with proper rest and recovery.
• Long-term fatigue occurs when recovery from short-term fatigue does not happen with regular rest.
  • Long-term fatigue typically arises from prolonged stress (weeks and months) without enough recovery time. This may lead to lower productivity, weakened immune response, and other health issues.

Physical Fatigue Management

Firefighters, supervisors, and incident managers need to find ways to reduce the occurrence of fatigue without recovery. We must acknowledge that stress is a necessary stimulus for your body to adjust. For instance, rigorous exercise puts physical stress on your body. And given the opportunity to recover, exercise leads to better aerobic capacity, strength, or endurance. However, you will not see the best results without adequate recovery.

Rest days and light workout days that include sustained pacing, stretching, and warm-up activities have been shown to promote and maintain muscle status while preventing the accumulation of physical stress that can lead to exhaustion. On the fireline, a host of other challenges exist to maintaining optimal nutrition, hydration, and sleep that help mitigate physical fatigue. Explore these in the discussion below. 

Discussion Questions:

In these common situations, how can you and your crew build in recovery strategies or minimize the accumulation of fatigue in these situations? For each, consider the roles of rest, sleep, hydration, nutrition, and environmental conditions.

• During critical training, including crew training, project work, and 1-2 hours of PT daily.
• Midsummer with crew available for initial attack and opportunity of one hour of physical training each day.
• On assignment at a large incident and constructing direct fireline with your crew for 10 straight days.