By Antonio Sini

Incorporate interval training into your exercise routine and you will see your fitness and performance improve quickly, typically in just a few weeks. There are numerous studies that show you can improve your endurance and cardiovascular fitness with intense bouts of intervals just one hour per week compared with five hours of traditional cardiovascular training. If you are like most of us, pressed for time, then this is one big advantage of interval training. Other benefits include:

• It’s a great way spice up your cardio routine especially if you’ve gotten bored with your workouts.

• It’s a proven way to help get rid of that last bit of troublesome excess weight. This is because your metabolic rate stays higher for longer after interval training and you end up burning more calories throughout your day.

• Your immune system responds positively to regular strenuous exercise. Interval training – due to its intense qualities – yields a heightened immune response thus helping your body fight off colds and other illness.

How does it work?

The proper way to do intervals is to push your body past the aerobic threshold for a moment and then recover by returning to your aerobic conditioning level. The aerobic threshold is the intensity where your body switches from burning a greater percentage of fat (aerobic) to a greater percentage of glycogen or carbohydrates (anaerobic) and is generally 85% of your maximum heart rate (train below 85% and it’s aerobic; train above 85% and it’s anaerobic). Heart rate is a good indicator of how hard you’re working, and it’s easy to measure, so it’s an ideal method for setting up and monitoring intervals. A very simply method for estimating your anaerobic threshold is to assume anaerobic threshold occurs at 85-90% of your maximum heart rate. Your maximum heart rate is measured by taking the number 220 and subtracting your age. For example a 45 year old would have a max heart rate of 175 beats per minute. Heart rates vary greatly between individuals and even within the same individual so use this number as an estimate of your actual maximum heart rate.  (For a more accurate method – CLICK HERE)

Lets get started!

For the sake of ease and accurate measurement I like to use a stationary bike. The first thing you want to do is warm up for 5 minutes at 65-70% of your max heart rate. Check your pulse after 1 minute and then again after 4 minutes to make sure you are in that range. After 5 minutes prepare to begin your intervals.

Beginner intervals

Increase the bike resistance to a level that feels fairly uncomfortable and continue pedaling for 30 seconds. After 30 seconds bring the resistance back down to where you had it before. Check your pulse to make sure your heart rate jumped up to 85% of maximum (you may need to add or decrease resistance on the next interval). Continue pedaling at the easier pace for 2 minutes, bringing your heart rate back to 70% of your max. After 2 minutes jack the resistance up for another 30 seconds before dropping it down again for a 2-minute recovery. Repeat this process four more times and remember to keep your pedals strokes even throughout the routine.

Example:
Warm up at level 4 for at least 5 minutes

Increase to level 10 for 30 seconds
Return to level 4 and recovery for 2 minutes

Level 10 (30 seconds)
Level 4 (2 minutes)

Level 10 (30 seconds)
Level 4 (2 minutes)

Level 10 (30 seconds)
Level 4 (2 minutes)

Level 10 (30 seconds)
Level 4 (2 minutes)

Cool down at level 2 for 3 minutes
Total cardio exercise time: 20 minutes

Advanced intervals

If you have a good cardiovascular base then you can push your body past the aerobic threshold for longer than 30 seconds. In this case we are going to warm up for 5 minutes at 70% of max heart rate then perform 1 minute long intervals at 90% of max. We’ll follow these all-out efforts with 2-minute recovery periods.

Example:
Warm up at level 6 for at least 5 minutes

Increase to level 15 for 1 minute
Return to level 6 and recovery for 2 minutes

Level 15 (1 minute)
Level 6 (2 minutes)

Level 15 (1 minute)
Level 6 (2 minutes)

Level 15 (1 minute)
Level 6 (2 minutes)

Level 15 (1 minute)
Level 6 (2 minutes)

Cool down at level 4 for 3 minutes
Total cardio exercise time: 23 minutes

Important!

Keep in mind that interval training is extremely demanding on the heart, lungs and muscles, and it’s important to have an OK from your physician before you start interval training. You should also have a solid base of overall aerobic fitness before performing high intensity training of any kind. Lastly, do not performing intervals more than two times per week to avoid overtraining.