You need to shake up your fitness program and lose weight, but you don’t really have any more time to devote to it. The perfect answer could be high-intensity interval training or HIIT for short. Interval training is not just for elite athletes anymore — everyone is doing it.

High-intensity interval training requires interspersing bursts of intense activity into your regular fitness program. “It’s a form of fitness training that alternates high-intensity work efforts with low- to moderate-intensity ‘recovery’ efforts,” explains Leigh Crews, a personal trainer in Rome, Ga., and a spokeswoman for the American Council on Exercise.

Don’t confuse interval training with circuit training. Circuit training is moving from station to station to complete a set of exercises. Circuit training can be all aerobic exercise, all strength training, or alternating between cardio efforts and strength training. “Many people mistakenly call this interval training when, in fact, it is a circuit,” Crews says.

When you’re circuit training, you don’t rest between the exercises that you do in sequence. When you’re interval training, you want to take short rests between intense repetitions of a single exercise.

How Interval Training Helps:

Adding interval training to your fitness program has both mental and physical benefits:

You lose weight faster. The more vigorous your exercise, the more calories you will burn, so even short bursts will help you lose weight.
It eliminates boredom. By varying the intensity of your exercises, it changes things up. Not only will your fitness program go by faster, but you won’t experience the drudgery that can come from doing the same routine every day.

You need to shake up your fitness program and lose weight, but you don’t really have any more time to devote to it. The perfect answer could be high-intensity interval training or HIIT for short. Interval training is not just for elite athletes anymore — everyone is doing it.

High-intensity interval training requires interspersing bursts of intense activity into your regular fitness program. “It’s a form of fitness training that alternates high-intensity work efforts with low- to moderate-intensity ‘recovery’ efforts,” explains Leigh Crews, a personal trainer in Rome, Ga., and a spokeswoman for the American Council on Exercise.

Don’t confuse interval training with circuit training. Circuit training is moving from station to station to complete a set of exercises. Circuit training can be all aerobic exercise, all strength training, or alternating between cardio efforts and strength training. “Many people mistakenly call this interval training when, in fact, it is a circuit,” Crews says.

When you’re circuit training, you don’t rest between the exercises that you do in sequence. When you’re interval training, you want to take short rests between intense repetitions of a single exercise.

How Interval Training Helps:

Adding interval training to your fitness program has both mental and physical benefits:

You lose weight faster. The more vigorous your exercise, the more calories you will burn, so even short bursts will help you lose weight.
It eliminates boredom. By varying the intensity of your exercises, it changes things up. Not only will your fitness program go by faster, but you won’t experience the drudgery that can come from doing the same routine every day.

No extras needed. You already have the equipment you need for your interval training because you’re already doing the basic workout. Interval training requires no special skills — the only thing needed is more effort on your part.
You increase your fitness levels. You will improve your ability to exercise and increase your stamina over time.
You reduce the time spent on exercise. You spend less time exercising, but you burn the same or more calories as with your normal routine.

Getting Started With Interval Training:

Anyone can add interval training to a fitness routine. For beginners who walk outdoors for exercise, you’ll need to find objects at regularly spaced distances when walking or running, such as telephone poles, and use them to judge your intervals. “You might start out brisk walking from one to pole to the next, then walking at an easier pace for three poles,” Crews says. As your fitness level increases, increase the speed of your walk or run for an additional pole or two.

Hills are another way to add interval training to your running or jogging workout. You exercise more intensely as you climb the hill and have a relatively easy effort as you come down. You may need to change your course to tackle more hills.

A more structured option is to go by the clock. Walk or run at an intense pace for one minute. Then walk or jog for one minute at a relaxed pace. If you’re really serious about it, Crews says, use a timer and a heart-rate monitor to time and pace your intervals. You can take the same approach when you’re biking or swimming.

When interval training, it’s important to create an obvious distinction between your work efforts and your recovery efforts. Make sure you work in the “somewhat hard” to “hard” categories for the work, Crews says, and the “low” to “moderate” categories for the recovery. Plan your interval training for one to three times a week. You shouldn’t do it every day, Crews says.

If you want to apply interval training to make your strength training workouts more intense, simply shorten the rest time in between sets. Not only will your workout time will be reduced, but you also will keep your heart rate up. A higher heart rate can help you burn more fat during your workout.

Why Interval Training Is Not for Everyone

Interval training is very demanding. Your body needs to be able to handle the stress and to recover from the damage you will incur. If you have any heart problems or circulation issues, interval training is not for you. Others who should avoid HIIT include people with diabetes, people who are obese, and those who very out of shape.

A qualified personal trainer can help you design the correct interval training program for your fitness level and your personal goals. Remember to always talk to your doctor before starting a new exercise program.