Heart Rate Training

“Get your heart rate up to ‘X’ beats per minute to really burn fat/calories/carbs.” This may be what you’ve heard from your friends, fitness instructors, and even health care practitioners. Now you think that when you exercise, you have to be in a special zone to get the best workout. So how valid is heart rate training?

What is your heart rate?

When you take your pulse, you are finding out how many times per minute your heart beats (also known as your heart rate). Your pulse is a measure of arterial pressure.

Taking your pulse

Before your workout, take your pulse by placing your index finger and middle finger along the side of your wrist under your thumb. Press down gently but with pressure until you feel your pulse. Never use your thumb, as it has its own pulse. You can also wear a heart rate monitor, which will give you constant feedback about your pulse rate.

Resting heart rate

Before you start exercising, you will be measuring your resting heart rate. A typical resting heart rate can be anywhere from 40 to 100 beats per minute, with women’s being faster than men’s. The lower your heart rate, generally the fitter you are.

Unusually low at 26 beats per minute, Great Britain’s Daniel Green’s heart was measured over a 24-hour period and found to beat extremely slowly—he holds the record for the lowest heart rate.

Exercise heart rate

When exercising, you will be measuring your exercise heart rate. To measure, stop moving for the duration of the timing period. If you’re on a bike, stop pedalling; if you’re on a treadmill, place your feet on either side of the machine. Take your pulse again on your wrist, or if it’s easier, at your neck. Place the same two fingers on the opposite side of your neck, under the jaw. Press lightly.

Recovery heart rate

During your workout, your heart rate will be faster than when you were at rest. The speed at which your heart rate comes back down after exercise is a great indicator of your fitness. This is called your recovery heart rate.

How many beats should your heart rate drop within a minute of stopping cardiovascular exercise? If you guessed 20 beats, you are right!

“That’s a safe place to be. If you can go down 20 beats from your maximum during a stress test in the first minute, that tells us that you have a very healthy heart,” says Nieca Goldberg, MD, a cardiologist and medical director at NYU Langone Medical Center.

Target heart rate

Not to be confused with your maximum heart rate (MHR), which is the highest your heart rate can go on a stress test and found by taking 220 minus your age, your target heart rate (THR) is calculated by this simple equation: 220 minus your age (MHR), multiplied by a lower zone (60 percent) and a higher zone (85 percent).

Goldberg says that your heart rate should not be too low or too high. Rather, you should be able to get to your THR and stay there for the duration of your workout (after warm-up and before cool-down).

If you can’t reach your THR or it stays too low over a period of time, you should check with your health care practitioner. Reasons for reaching your THR too fast or slow include being out of shape or taking certain medications.

“Cardio training over time will make it harder for you to reach your THR; it will take longer to reach your THR,” says Goldberg. This is because your heart works more efficiently as your fitness improves.

Heart rate training

To get the best health benefits of aerobic training, the American Council on Exercise suggests that you exercise at an intensity that stimulates the aerobic system for 20 to 60 minutes per session. For beginners, start with even five to 10 minutes.

Aerobic training zone

Working out your cardiovascular system results in better lung capacity, a stronger heart, more endurance, and possibly weight loss. Qualities of the aerobic zone include

• exercising at 70 to 80 percent of your MHR
• being able to speak briefly
• running
• starting to sweat

Fat-burning training zone

For years, experts have taught the theory of the fat-burning zone, a lower intensity state that burns about six to 10 calories a minute. Qualities of the fat-burning zone include

• exercising at 60 to 70 percent of your MHR
• being able to talk comfortably
• jogging slowly at a steady state

Now, however, we know that you will burn fat no matter how high your heart rate is! Keeping your heart rate below a certain number to burn fat is not an issue.

In a 2008 study, women who worked out with a high intensity interval training program three times per week for 15 weeks had a greater loss in body fat than women who worked out for the same amount of time at a steady state.

A 2009 study, when examining the fat-burning zone and aerobic zone, demonstrated there was an overlap; it indicated that training for fat oxidation and aerobic fitness are not mutually exclusive and may be accomplished with the same training program.

So next time you’re at the gym, and you see one of those charts with colourful blocks of numbers for each zone, remember that you will get benefits from being in any zone—and your heart will thank you for it.

Keep it low

Working out too hard aerobically is not for everyone. If you fit any of the following descriptions, you should seek medical advice before training at your target heart rate:

• people on beta blockers or calcium channel blockers
• people taking respiratory medication
• diabetics
• pregnant women with complications

Benefits of aerobic exercise

The following exercise modalities offer ways to lower your risk of coronary heart disease and diabetes, reduce weight, and lower stress levels:

• running—high impact
• swimming—low impact
• cycling—low impact
• dancing—low or high impact
• aerobics classes—low or high impact