Energy Requirements in Firefighting

In the December 2010 issue of The Journal of Strength and Conditioning Research, there is a paper titled “Energy Costs and Energy Sources During a Simulated Firefighting Activity.” It details research done at the Department of Human Movement and Sport Science, University of Rome Foro Italico and the Department of Physical Training of Italian Firefighter Corps, Rome, Italy. The authors set out to determine how much energy is needed to complete various firefighting activities and precisely which metabolic sources provide this energy. It has some very interesting findings.

Caution, Science Content

Their aim was to determine the energy requirements and the contribution of both the aerobic and anaerobic energy sources in a simulated firefighting intervention. They also wanted to determine the differences in mean VO ₂ max and heart rate during varied firefighting tasks and to verify the relationship between time of job completion and firefighter fitness level.

They had the subjects perform four consecutive simulated firefighting tasks as quickly as they could one after another. The tasks were as follows: perform a child rescue that involved climbing a fireman’s ladder and descending a three-story building carrying a 20-kg (44-lb.) child dummy, followed by a 250-meter run; then complete a maze escape in a dark chamber, followed by a second 250-meter run. All tasks were done in full turnout gear wearing SCBA. This last item is very important. Most tests on firefighters done in laboratories are not done in full gear, which in my opinion makes no sense at all.

The 250-meter runs were included to simulate tasks of high physical but low cognitive demand (closed skill), and the child rescue and maze escape tasks simulated lower physical but higher cognitive demands (open skill). They collected data to compare the energy demand and consumption separately for each activity using a metabolimeter. Lastly, they examined the relationship between fitness level and time to job completion.

 

Results Discussion

What they found wasn’t really for the most part surprising. Simply put, the interventions studied posed a high physical demand on the firefighters and that demand was sustained primarily by aerobic metabolism. The closed and open skill tasks differed in mean VO ₂ max and heart rate, and there was no relationship between time of job completion and fitness level of the tested firefighters.

As one would have guessed, the running task put the highest physical demand on the subjects and the darkened maze escape was cognitively the most difficult, took the most time, and had the largest variation in completion time between individuals.

The most concerning discovery was regarding recovery. Passive recovery was found to be wholly inadequate in sufficiently reducing the accumulated cardiovascular and thermoregulatory strain of the previous workload. These findings indicate that the development and implementation of a comprehensive cooling strategy needs to be a priority for all departments. Just sitting and drinking some water isn’t enough for recovery. There are new active cooling options developed primarily for sporting activities that may provide much-needed technological improvements in rehabilitation at a fire scene.

It is apparent that job demands vary greatly between the tasks encountered while fighting a fire. The highest physical demand was found during the running task. Firefighters don’t always get to run in an unobstructed straight line; they may need to sprint though hazards when rescuing a victim or escaping from a dangerous environment. It is therefore recommended that firefighters train not only in basic aerobic fitness but also in speed and agility.

The somewhat surprising finding that time to job completion and fitness level were not related may be partially explained by the that fact that all of the participants were full-time firefighters with a high level of training, firefighting expertise, and aerobic fitness. These results must be tempered on the local level by considering the fitness and training of your individual department.

At the completion of the four evolutions, high lactic acid levels were observed and heart rates were still at elevated levels 30 minutes after the final task was completed. Heart rates increased from the first task (child rescue) on and remained elevated even while firefighters mostly walked while negotiating the darkened maze escape. The continued elevated heart rates accompanied by lower oxygen demand give credence to the conclusion that the psychological and emotional stress of working in unpredictable environmental conditions imposes a huge, persistent cardiac load on firefighters, especially while experiencing an elevated thermoregulatory strain and increased cognitive workload.

Observations

A couple of things jumped out at me while reading this paper. One is a comparison of the Italian firefighters and the firefighters I have tested. The ages were very similar, about 33 years old. The heights were similar as well, about 5’10”. I can’t speak directly to skills training, but I believe that the firefighters I have worked with are highly skilled and well trained and would compare favorably with those in the study. The biggest difference I noticed was in body weight. The Italian firefighters in the study averaged 165 lbs., and the firefighters I have tested average 199 lbs. That is a considerable difference, and I would have to believe that it may have some effect on task performance but almost certainly a significant effect on recovery.

Conclusions

It was noted that The Italian Firefighting Corps has no organized, structured physical training or required yearly evaluations to ensure that their members meet minimum standards necessary to safely and efficiently accomplish the tasks required in firefighting. This appears to be the norm in the fire service internationally and is no different than many fire departments in the United States.

The authors of this study conclude that their results strongly indicate a need for sound physical training programs for firefighters, and that firefighters may be more likely to be involved in regular exercise when time can be scheduled during their shift and on-site facilities are available. Their second conclusion regarding the increased likelihood of voluntary participation while on duty if facilities and time are provided, in my opinion, wasn’t supported by the data and in my experience is only marginally true. So long as exercise is strictly voluntary, participation rates will be less than stellar.

Despite that single criticism, I would wholeheartedly agree with their conclusion regarding the need for improved fitness programs.

Required physical training should be a regular part of every department’s daily activities. The feeling among the rank-and-file that regular fitness testing is a threat needs to be reevaluated. Ensuring that every member of a department is healthy, skilled, fit, and strong seems to me to be very reasonable and a benefit to the individuals, the department, and the community.

Too many firefighters end their careers dealing with a disability that might have been avoided. Firefighting is difficult and dangerous enough without the added risk of being physically unable to adequately handle the challenges. I have never met a firefighter who didn’t want to be the best he or she can be and when given the opportunity for additional training didn’t take advantage of it—that is, except in the area of physical fitness. For some reason, improving fitness is a tough sell even when the department provides incentives, time, education, and opportunity.

A professional firefighter wouldn’t tolerate fellow firefighters who didn’t maintain and improve their firefighting skills, yet they turn a blind eye to those who have allowed their health and fitness to slide even to the point where they are putting their life and the lives of others at risk. Perhaps a little positive peer pressure needs to be applied by those in the department who are in the forefront of firefighter fitness.

With the understanding of the importance of your mission, you can work among your peers to change attitudes and improve the overall health and fitness of the fire service and, by example, society in general. It is a big job and it won’t be easy, but that has never stopped you before.