Get Moving

Use low- & high-intensity training to improve your aerobic fitness

Strength is obviously a huge factor in successful fireground operations. Many firefighters have survived in the service just by being strong. And while strength is good, it can only carry you so far; aerobic fitness carries you the rest of the way.

Last month we defined aerobic and anaerobic activities, and discussed how to measure aerobic fitness. The question on everyone’s mind now: How do I make improvements in my aerobic capacity? Before we delve into the methods of developing your aerobic fitness, let’s address why doing so is important.

Benefits of Aerobic Fitness
Aerobic fitness is critical when the situation calls for a sustained effort. The less aerobically capable run into trouble when they get too far into a structure and run out of gas, become ineffective during a rescue operation or—the curse that haunts the fire service LODD statistics—suffer a heart attack. Although being aerobically fit is not a guarantee you won’t suffer a cardiac episode, aerobic conditioning enhances your cardiac health, therefore improving your odds of avoiding such an experience.

Additionally, several studies show that maintaining aerobic fitness as you age can actually slow the physiological aging process. Staying fit also reduces your risk of a number of common chronic diseases, including obesity, hypertension, Type 2 diabetes and several cancers, such as colon, breast, prostate and lung cancer.

Let’s face it: Some people are blessed with natural aerobic ability; the rest must work at it, which becomes painfully apparent as we age. The interesting thing, however, is that although there is a natural deterioration in all components of fitness as we age, it doesn’t have to be as profound as many think. We’re often too quick to hang our hats on the theory that, “They can’t expect us to be able to do the same things the younger firefighters can do.” Although that may be true, it is completely reasonable to expect your entire firefighting team to perform to a minimum standard. For some, this may be a more involved process than for others. Remember, fitness maintenance is much easier than playing catch up, both mentally and physiologically. If you maintain your fitness levels as you mature, your maximum potential will be higher than if you don’t. And even if you’ve lived a more sedentary lifestyle up to this point, the sooner you start getting fit, the more potential you’ll retain. The bottom line: Adhere to the mindset of “Get fit and stay fit.”

Aerobic Improvement
Some people believe aerobic improvements can only be made by spending long, tedious hours pounding the asphalt. We’re happy to report this is only part of the equation. As we discussed last month, there are three critical components to a successful aerobic training program: rhythmic activity, the use of large muscle groups and a sustained effort. This means you must engage in at least 20 minutes of a repetitive activity that uses leg, gluteus, chest or back muscles. People generally use combinations of these muscles during most aerobic exercises.

Now, back to pounding the asphalt. When it comes to aerobic training, many people get sucked into a monotonous routine, exercising 20-plus minutes, plodding along at the same pace, day in and day out. If that works for you, great. But it doesn’t work for many of us who need variety in our routines and/or who want to continue improving our aerobic fitness through effective endurance training.

But what actually defines aerobic improvement? In layperson’s terms, it simply means being able to push harder for a longer duration without experiencing an extremely labored effort. (You’re laboring when you can’t say five words without gasping for a breath.) In technical terms, aerobic improvement is represented by a higher VO2max score, or a higher anaerobic threshold (see “Get Moving, Part 1,” December issue, p. 86, for a refresher on these topics).

Improving aerobic fitness relies on four things: the intensity of your workout, the length of the workout, how often you work out and the type of exercises performed. To get the maximum benefit from your training, pay close attention to your heart rate, which is a good measure of intensity. Your workout intensity will vary depending on the type of workout and how hard you actually push yourself.

Varied workout intensity will likely yield the best results. If you’re relatively fit, you can divide your effort between high- and low-intensity training. Low-intensity training is any exercise in which you exert between 55 and 75 percent effort. Believe it or not, you may have to slow your sustained aerobic efforts to fall within that range.

High-intensity training is any exercise in which you’re exerting between 80 and 100 percent effort. This is not a sustained effort, but rather high-intensity effort for a short duration. (For more information about using workout intensity levels to determine your target heart rate, see the sidebar “Heart Rate 411” on p. 112.)

High-intensity training is generally performed as interval training. Because you cannot maintain that high level of exertion for an extended period of time, you should cycle in periods of recovery. You can utilize this technique while hill training, exercising on various machines (i.e., stairclimber, versaclimber, treadmill) or performing fartleks—a form of conditioning in which the speed or intensity varies. Interval training can be very beneficial to improving aerobic capacity; even marathon runners incorporate intervals into their aerobic training programs.

Develop a Workout
Once you’ve determined your target heart rate (or range) for both high- and low-intensity workouts, it’s time to develop your workout program. But how should you divide your time between the high- and low-intensity workouts? We recommend an 80:20 ratio, with 80 percent of your time spent on low-intensity training and 20 percent on high-intensity (interval) training. For example, if you spend 100 minutes each week on aerobic training, 80 minutes should be at a low intensity and 20 minutes should be at high intensity. Keep in mind: If you do 10 1-minute intervals with 4 minutes rest between each one, only the interval time (10 minutes) counts toward the 20 percent weekly high-intensity training.

Interval training not only helps improve your aerobic capacity, it also breaks the monotony of aerobic training. When designing interval workouts, your foundation is the work-to-rest ratio, which relates to distance or time. If you’re just starting out, your ratio will include a little work and much rest. For example, you could sprint 200 meters and recover with a 400-meter walk, or you could exert for 1 minute and recover for 4 minutes.

As your fitness improves, reduce the work-to-rest ratio, gradually increasing the work and reducing the rest. For example, you could now sprint 200 meters and recover with a 200-meter walk, or you could exert for 2 minutes and recover for 2 minutes. A 1:1 work-to-rest ratio is pretty intense. Remember: The high-intensity efforts are at 80–100 percent effort, and only the time spent on the high-intensity portion of the training applies toward the 20-percent high-intensity total for the week.

Additional Notes
If you’re just getting started with your fitness program and you’re not in good aerobic condition, start slowly. You may reach your target heart rate for low-intensity effort with just a brisk walk. If that’s where you need to start, then so be it. You’ll improve quickly, especially if you’re dealing with weight issues as well. As you increase your activity and pay close attention to what you eat, you’ll quickly see aerobic improvement. We do not recommend high-intensity training for people in very poor physical condition. Be patient, and as your conditioning improves, you can slowly (and gently!) incorporate the principles of high-intensity training into your fitness program.

Also, varying your training will keep it interesting. Don’t spend all your time performing one exercise. For example, run with a friend, or ride a stationary or regular bike for 20 minutes and then move to a treadmill or elliptical trainer for 10–20 minutes. This breaks up the monotony of the workout and makes time pass faster. Plus, you’ll end up exercising for longer than you would if you stuck with just one exercise.
The most important thing: Keep your heart rate within your target range throughout the workout. Train smart, and you’ll see the aerobic improvement. Don’t get discouraged. The bottom line: Try to use this information to create your optimum workout. The closer you can come to following these guidelines, the more effective your workouts will be.

Captain Martha Ellis has been a firefighter with the Salt Lake City Fire Department (SLCFD) for more than 13 years, serving as a firefighter, engineer, media technician and ARFF training officer. She has won the Scott Firefighter Combat Challenge Women’s Division five times, and held the world record for 8 consecutive years. She is currently the fire marshal for Salt Lake International Airport, and she works as a certified fitness coordinator for the SLCFD.

Captain Jeff Ellis of the Murray (Utah) Fire Department (MFD) has served for more than 23 years as a firefighter, engineer, hazmat technician and shift training captain. He has been a certified fitness coordinator for the department since 1996. As a competitor in the Scott Firefighter Combat Challenge, he has won two overall world championships and three Over 40 world championships and helped MFD take the team trophy. He has been active in teaching all aspects of firefighting, including swiftwater rescue and fitness and nutrition in the fire service.

E-mail your fitness-related questions or comments to Jeff and Martha at mfit2serve@gmail.com.