The Firefighter Fitness Pentagon: Part 3 – Muscular Strength and Endurance

Feb. 1, 2004
Rod Hammer discusses how increasing muscular fitness will allow you to perform fire suppression activities better and reduce on-the-job injuries.
Everything you do during fire suppression requires muscle activity. Whether you are pushing, pulling, lifting, bending, holding, carrying or even just standing, your muscles are active. It is because of this activity that you are able to function on the fireground.

Each task you attempt to perform requires different muscles to activate in a different manner. Simply walking around in your bunker gear requires activity from your abdominal, back and leg muscles. Add to that the extra weight of a hose pack and then start climbing stairs and you see an increase in muscle activity of the already burdened back and leg muscles. Deficiencies in muscular fitness may lead to poor performance or even injury. Conversely, increasing muscular fitness will allow you to perform fire suppression activities better and reduce on the job injuries.

Several researchers have quantified the strength requirements of fire suppression. In 1992, Gledhill and Jamnik measured weights and forces of many fireground activities. They found the most common activities included lifting and carrying objects up to 80 pounds, pulling objects up to 135 pounds and working with objects in front of the body weighing up to 125 pounds. While these may be the most common, we all know that there are extreme events that we may encounter as well. If your 240-pound partner collapses, you have to have the strength and endurance to pull him out of harm’s way. It is critical that you maintain a strength program to have the necessary strength and endurance to safely perform all aspects of your job.

Muscle activity can be divided into two broad categories: strength and endurance. Although the two categories are related, it is important to identify the differences between them. Muscular strength is the maximal ability of the muscle to contract. Strength is the heaviest thing you can lift one time.

Endurance is somewhat different. It is the ability of your muscles to persist in an activity. Endurance is the number of times you can repeat a movement or length of time you can maintain a contraction. If you apply these definitions to weightlifting, strength is how much weight you can lift one time, while endurance is the number of times you can lift a lighter weight.

You should now be able to classify fire suppression activities into either the strength or endurance category. Activities that are not sustained such as hoisting a chain saw, raising a ladder and advancing a charged line are strength activities. Repeatedly tearing at a ceiling with a pike pole, directing a water stream from a handline or stabilizing a ladder are endurance activities. Your ability to persist in doing many different strength activities during fire suppression could be considered one big endurance event. Strength and endurance are not mutually exclusive.

Assessment. Muscular strength and endurance can be measured to give you an idea of where you stand in relation to yourself and other firefighters. I will describe several assessment methods, then provide you with reference values for each test.

Two tests used to determine muscular strength and endurance are the one repetition maximum (1 RM) test to measure strength and the YMCA bench press test to measure endurance. Maximal testing requires the user to find a weight (through trial and error) that is the most he or she can bench press one time.

According to researchers, the 1 RM test is safe for adults if no other pre-existing musculoskeletal issues are present. Safety should be the first concern when testing muscular strength. It is important that the firefighter maintain good form while performing the test. When performing the bench press, the back should be firmly pressed against the bench. Arching the back must not be allowed. Do not perform this test if there is or has been a back or other musculoskeletal injury that has not been cleared by a physician. The 1 RM test described by Kramer and Fry is conducted as follows:

2. During a one-minute rest period, have the firefighter stretch the muscle group.

3. After the rest period, the firefighter presses 60% to 80% of the expected 1 RM weight three to five times.

4. Next, increase the weight conservatively and have the firefighter attempt his 1 RM lift. This will be the most weight the firefighter thinks he can lift. If successful, the firefighter will rest three to five minutes before attempting the next weight increment. Follow this procedure until the firefighter fails to complete the lift.

Obviously, a larger person should be able to lift more than a smaller person. To include this consideration, we factor in body weight. This is known as relative strength. To determine your relative strength, divide your 1 RM by your body weight. According to the Cooper Institute for Aerobics Research, above-average males age 20-29 should have a relative strength of 1.22, age 30-39 should be 1.04 and those 40 -49 should have a relative strength of 0.93. Above-average females 20-39 should have a relative strength above 0.42, those age 40-49 should be above 0.38.

Muscular endurance is measured by performing as many repetitions as possible with a given weight. The YMCA bench press test works well to measure this. To conduct this test, male firefighters will use an 80-pound barbell and female firefighters will use a 35-pound barbell:

2. With the firefighter lying in the standard chest press position, instruct him to press the weight to the cadence of the metronome. Each time the metronome clicks, the firefighter should have his arms extended. Advise him to go slower if he is pressing faster or more often than the cadence.

3. Count the number of complete repetitions the firefighter is able to press while still maintaining the cadence. If he slows down or is unable to continue, he must stop. You should spot the bar and be prepared to take it from the firefighter’s hands as soon as he is finished.

According to the YMCA protocol, above-average males age 18-25 should be able to press 30 repetitions, males 26 35 should be able to press 26 repetitions and males 36-45 should be able to press 24 repetitions. Above-average females age 18-25 should be able to press 28 repetitions, females 26-35 should be able to press 25 repetitions and females age 36-45 should be able to press 21 repetitions. Measuring strength and endurance of the chest muscles is only an indicator of overall strength. Obviously, all major muscle groups must be exercised to properly strengthen the body to work in extreme environments.

Training. There are nearly as many strength training methods as there are people to promote them. Go to any bookstore and you will find a shelf full of books telling you how to get a body just like Arnold Schwarze-negger’s. That’s fine if your goal is to look like that. I would recommend a more practical approach. As I said in the beginning, muscular strength and endurance is critical to fight fires. Therefore, you should look for a program that will promote strength and endurance needed for fighting fires. The number-one goal should be functional fitness, not muscle size.

Functional fitness describes the theory that you train to perform the tasks that you will encounter. I don’t ever remember lying on my back at a fire and pressing 120 pounds (although I’m sure someone out there has.) On the other hand, I have pulled, dragged and carried more things than I can count. I have dragged charged hose and tossed furniture out of homes, carried and hoisted ladders and have even thrown bales of hay. I have chased fire in walls, pulling lathe and plaster, until I almost threw up, but I have never had to perform a chest press. What I am getting at is this: traditional strength training exercises are good. In fact, they are great if you are trying to focus on specific muscles, but more general training that reflects the motion of activities on the fireground is a better use of your time.

According to National Fire Protection Association (NFPA) Standard 1583, we should exercise using the following movement patterns each time we strength train:

2. Upper-body pull – Pull-ups, lat pull-down, seated row, biceps curl, etc.

3. Lower body thrust and extension using the hip and knee joint – Lunges, squats, seated leg press, etc.

4. Knee flexion (hamstring) – Standing or seated leg curl, etc.

5. Abdominal contraction – Modified sit-ups, crunch routines, etc.

6. Back contraction – Kneeling leg extension, double knee to chest, trunk extension, etc.

If you do this, you will have a balanced weight training program that will promote whole body strength rather than the isolation and focus of certain muscles to the detriment of others. All too often, men specifically want to have a big, broad chest with huge, “look at these” arms. They focus all their energy on working the upper body and end up with little toothpick legs that can’t support their upper-body strength. That is why you should focus on motion patterns rather than specific muscle groups. For instance, squat exercises, when performed correctly, activate the whole body, including abdominal and back muscles. Squats require your muscles to work together to lift and carry in a manner that is very close to activities on the fireground. Priority should be placed on exercises that involve activation of multiple large muscle groups.

One of the most critical but overlooked aspects of strength training is developing the core muscles of the body. These include the abdominal and back muscles. Everything you lift with your upper body has to be supported by your abdomen and back. Everything. If you ignore this area during strength and endurance training, you will not achieve your best performance and you will have a higher risk of injury. Abdominal and back muscles are strengthened by sit-ups and push-ups as well as a series of back specific exercises.

Women firefighters need to train their muscles as much as men. They are expected to do the same job. Some women are under the misconception that strength training will cause them to get huge muscles. This is not the case. Women don’t have the testosterone levels to promote large muscle growth. They can get strong and be fit and still not have huge muscles. It goes almost without saying that drugs, especially illegal steroids, should never be used to increase strength and endurance.

Care should be taken when strength training, especially when unsupported. You should focus on proper form rather than on the amount of weight you can lift. You can easily injure yourself by trying to lift too much weight too early in your training routine. Also, focus on your abilities and growth; don’t compete with others to see who can lift the most. You wouldn’t want to injure yourself and throw your firefighting career away just for a chance to say you’re the strongest.

Intensity. The intensity of your workout is the amount of weight you lift. You should select a weight such that you are able to complete 5 to 20 repetitions. To maximize muscular strength, NFPA 1583 recommends lifting weights that are heavy enough so that you are only able to complete five to eight repetitions. You should complete three to six sets of each exercise. To increase muscular endurance, you should lift weights that allow you to complete between 10 and 20 repetitions and three to six sets of each exercise. Remember to warm up prior to lifting heavier weights.

Rest intervals between sets again depend on the type of muscle changes you wish to see. For strength, NFPA 1583 recommends two to three minutes between sets. To increase endurance, it recommends 30 seconds to two minutes. Finally, if you wish to incorporate a low-level aerobic component to your strength workout, you can do a circuit training program with only 15 to 30 seconds between sets.

As you train, your ability to lift more weight will increase. This is one of the motivating factors in strength training. You will require more weight to limit the number of repetitions you are able to complete. As you train, you should vary your exercises to keep from becoming stagnant and giving up.

Frequency. Frequency depends on several things. NFPA 1583 lists them as initial level of conditioning, individual goals, health status of the individual, volume and load of exercise, and type of movement performed (multi-joint vs. single-joint.) According to the American College of Sports Medicine, weight training should occur at least two times per week.

Research has shown that individuals who are new to strength training that exercise two times per week see the same gains as those who strength train three times per week. After some experience is gained, moving to three times per week has an added benefit. The National Strength and Conditioning Association recommends three days per week on alternating days. A minimum of at least 48 hours should pass before repeating strength training activities in major muscle groups to allow time for the muscles to heal.

Equipment. There are several classifications of strength-training equipment: free weights, weight machines or systems. Free weights are inexpensive in comparison to other types of equipment and have a wide range of exercises. The disadvantage is that you should have a spotter to help you exercise so you don’t get hurt. There is nothing to stop the weight from crashing down if you can’t lift it.

Weight machines or weight systems differ from free weights in that all of the resistance is applied through a series of pulleys and cables. Most have multiple stations that help you to get a complete body workout. They are typically more expensive than free weights and often allow only one user to work out at a time. The user does not need a spotter to safely lift and the weight selection is easier to change than free weights. On the other hand, the machine dictates the motion path you must travel. If you are larger or smaller than average, the motion path may not be correct for you. Adjustable seats and backrests help alleviate this problem, but they still cannot be as adjustable to your body as free weights.

Calisthenics do not require any equipment purchase. They use your body weight for resistance and generally provide a good workout. They are limited by your weight so calisthenics lend themselves to endurance exercises rather than strength exercises.

You can go out and spend thousands of dollars to equip a gym with the latest exercise equipment. Sometimes such a purchase becomes a motivating factor to exercise. If you pay for it, you may as well use it. There is excellent equipment on the market that will meet your needs, but there are a few things you should look for in strength training equipment:

2. Does it allow you to do the various exercises you need to get a complete body workout? Some machines are very specific and allow you to perform only one exercise. These machines are typically very stable and have enough weight, but cost much more than multi-purpose machines. You have to purchase several machines to get a full workout.

3. What is your budget? As with number 2 above, buying single-station machines that are specific to one exercise is very expensive. Some manufacturers make equipment that can do multiple exercises. A bench and a set of free weights can do many more exercises than some of the isolation machines.

4. Does it fit your body size? Is the bench long enough to fit all the members of your department? Are seats and other stops adjustable to fit different sized users?

Another option is to check out local gyms or community facilities and see if you can work out there. They already have the equipment set up and many will give firefighters a reduction in rates to exercise at their facility.

Muscular strength and endurance is vital to working on the fireground and having a long and successful career as a firefighter. Whether you are new to the service or a veteran with 30 years of experience, strength training will benefit your lifestyle both in and out of work. The combined strength and endurance components need to be trained if you want to be able to fight fires most efficiently. It doesn’t have to cost a lot of money or take a lot of time. It just has to be done.

Rod Hammer is a captain and training officer with the Lewiston, UT, Volunteer Fire Department. He has a master’s degree in exercise science and is the director of Human Performance Research at Icon Health and Fitness, a manufacturer of fitness equipment. Hammer also is the fitness coordinator for the Cache County Fire District. He consults with career and volunteer fire departments to establish firefighter fitness programs. Hammer can be reached via e-mail at [email protected].

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