The F.I.T.T. principles can be summarised as Frequency, Intensity, Time and Type. By following these scientifically devised principles you will be ensuring that you get the most out of your workouts.

1) Frequency - you should exercise between 3-5 times per week. If you are doing lighter exercise such as brisk walking, you should exercise more often than more strenuous exercise.

2) Intensity - how hard you work out is measured on an individual basis by reference to your heart rate. The heart rate you should be aiming for is between 50 - 85% of your maximum heart rate. Your maximum heart rate is calculated as 220 - your age.

For example, if you are 40 years old your maximum heart rate is calculated as: 220 - 40 = 180 beats per minute

Your target heart rate is then calculated as between: 50% x 180 = 90 beats per minute 85% x 180 = 153 beats per minute

So you should be exercising with your heart rate between 90 and 153 beats per minute to have an effect. If you are less fit you can be working out towards the bottom end of the scale. As your fitness improves you may want to work out between 65-85% of your maximum heart rate.

3) Time - To have a significant effect, you should be working out for around 30 to 45 minutes at each session. You can still get a benefit by exercising for shorter periods but 30 to 45 minutes will give you optimal results.

4) Type - A great benefit to using an elliptical trainer is the options that it provides. You can work out the legs and arms at the same time. You also have plenty of different options in the computer. Don't always just do the same exercise each time. Vary your elliptical trainer workouts and you will get a greater benefit from your exercise. Looking for a quality home elliptical trainer? Check out our free guide to see whether you should buy Proform elliptical or a Nautilus elliptical machine.