Spice up your Cardio with a Dash of Intervals

Written by Libby Norris

We know that cardiovascular training provides us with many valuable health benefits and is a key component in a well-balanced fitness program. Despite the upsides however, it can often be a challenge to find the time or the motivation to fit enough cardiovascular activity in to achieve your goals.

To make your cardio training more fun, interesting and efficient, add intervals!

Interval training has been used by athletes for years. One of the first forms of interval training was called "fartlek" which involved alternating short and intense burst of activity (usually running) with slower ones. The English translation for this is actually "speed play" and perfectly describes the process.

In athletic training, intervals are precisely measured, matching the demands of a given sport to produce specific results. However, you don't have to be an Olympic or professional athlete to use and benefit from interval training. Once you learn the basics, you can apply them at the gym or at home.

Interval training works both the aerobic and the anaerobic system which use different energy systems. Your aerobic system, which we are more familiar with and use as we walk around daily, works with oxygen. The anaerobic system, on the other hand, works without oxygen and is used for short and intense burst of energy like running up a flight of stairs or racing to catch a bus! During this more intense interval, a by-product called lactic acid is produced and is related to that burning sensation you sometimes feel in your muscles and often stops you from going any further!

During intense interval your metabolism spikes and you burn more calories, but you also benefit after the interval. Once you reach the top of the stairs or catch that bus and stop, you enter the "recovery phase" where you feel like you literally have to catch your breath. Although you've stopped or slowed down, the heavier breathing you feel is your body repaying an "oxygen debt". At this point, your metabolism is still revving higher as your heart and lungs work together to catch up and recover.

The speed play with interval training ends up being beneficial on many fronts. Interval training:
- Is efficient - provides a greater amount of work or calories burned in a shorter period of time
- Is effective - enhances the utilization of energy sources including energy from fats and carbohydrates
- Is fun - provides a lot of fun and change which can help to increase both your intensity and your adherence or your ability to stick with your program
- Is safe - can help to reduce the risk of injury or overtraining by adding more variety and balance in your training and workouts

Intervals are very easy to add in to your existing training. To spice up your regular cardio workouts add in bursts of intensity at regular intervals using either time or distance - walk for 30 seconds, jog for 10; walk 3 blocks, jog one block.

Intervals can be used with any cardio activity including walking, jogging, skipping, skating, skiing, stair climbers or elliptical machines.

Here's your formula:

Start slow with very short bursts and longer recovery times. Try to be specific and track your work to rest ratios to track your progress. As you build your strength and endurance, start to play with and change those ratios to increase the work time. Always allow your body time to recover - you should always feel comfortable but challenged!