Interval training for a stronger heart

It helps build cardiovascular fitness with shorter workouts

​Have you heard about interval training but aren't sure how it works and whether it's right for you? Interval training simply means alternating between short bursts of intense exercise and brief periods of rest (or a different, less-intense activity). The payoff is improved cardiovascular fitness.
You can give interval training a trial run simply by altering your current workout routine. To get the cardiac boost from interval training, you have to be willing to push yourself close to your limits—at least briefly. Three 20-minute sessions per week could add zest to your exercise experience and enhance cardiovascular fitness.


​What is interval training?
That seesaw relationship between exercise intensity and duration is what makes interval training work—but you may need to break a sweat. "High-intensity basically means exercising at a higher intensity or velocity than you could otherwise sustain for five to 10 minutes before becoming exhausted," in interval training, "you do high-intensity exercise for a minute, then rest, then repeat."

Here are a few ways to adapt your normal workout to a session of interval training:

• Swimming. Swim one lap as fast as you can. Rest for about the same time as it took you to swim the lap. Repeat.
• Walking. Walk as fast as you can for a minute or two. Then walk at a leisurely pace for the same period. Repeat.
• Gym machines. Treadmills, elliptical trainers, and stationary cycles often have a built-in interval training function to put you through your paces.

What are the benefits?
Interval training allows you to accomplish the same amount of exercise "work" in less time. That could make workouts easier to fit into a busy day or open a time slot to add some strength training. If you can reduce your moderate 30-minute workout to 15 or 20 minutes of interval training, the cardiovascular benefit should be about the same.

Is it safe?
In an otherwise healthy person, interval training should not present major risks, as long as you don't dive in too fast. "If you haven't done this before, begin slowly," "As you find it easier to exercise, you can increase the intensity."
If you have heart disease or high blood pressure, talk to your chiropractor before starting interval training or any other new exercise program—especially if you've been relatively inactive until that time.

How to get in the aerobic zone
Aerobic exercise gets your lungs and heart pumping to deliver the oxygen to your muscle cells, which use it to produce energy. You can use your heart rate to find the level of exercise that gets you in the aerobic zone and enhance cardiovascular fitness. Subtract your age from 220 to roughly approximate your maximum heart rate during exercise. Exercising at between 60% and 70% of your estimated maximum heart rate is sufficient to build cardiovascular fitness. If you can gradually condition your way up to 80%, the fitness gains will be even more noticeable. Using a wearable heart rate monitor can help you stay in the aerobic zone and show the benefits as your fitness improves.

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