Interval training is a very effective way to improve your fitness levels and has been proven in at least two scientific studies to induce greater weight loss than simply exercising at the same intensity for long periods.
Interval training consists of repetitions of high intensity work followed by periods of low intensity ‘rest’ periods and enables the body to train at high intensity without burning out. An example of an interval training session is called ‘walk back running’. You begin by sprinting at maximum effort for a set distance of 100 meters and then stop, turn round and walk back to the start point. Once you have got back to where you started, the sprint part is repeated and so on until a number of repetitions have been completed, usually around eight. Hill sprinting is also a form of interval training.
Another example, which was developed by the Swedes, is called ‘fartlek’ running which translates into ‘speed play’. In this case, a run of say three miles is split into ‘intervals’ and can done while out running on the road. It involves running at low intensity for a short while which is then followed by a sprint for a short distance. After the sprint, the athlete will then revert to a slow jog before repeating the sprint further on.
To do this while out on the road, you could count the number of lampposts you jog past and every 10 or so, sprint to the next one at 100% effort, jog the next ten and so on.
How it works
Interval training can be incorporated into any sport and can be performed while running, swimming, rowing, or any other physical activity. The big advantage is that interval training works both the anaerobic and aerobic system. While working hard at full intensity, the anaerobic system uses fuel stored in the muscles which works without oxygen of which lactic acid is the by-product. At this point, we experience burning muscles and put us into oxygen debt, which explains why we cannot maintain such high intensity for long.
During the rest phase, the aerobic system makes up for the oxygen debt and breaks down the lactic acid, using oxygen stored in carbohydrates to convert it to energy. Once the lactic acid has been broken down, we can continue again at high intensity.
The big advantage of interval training is that a training session can be much shorter than normal as the work is of a much higher ‘quality’ and the body learns to take in and use oxygen and deliver it to the muscles more effectively, which means we can increase our training intensity without ‘over training’.
Interval training also avoids ‘repetition’ injuries associated with exercising at the same intensity for extended periods. It is also widely accepted that more calories are burned during short interval sessions when compared to longer sessions of lower intensity work. If you want to shift a few pounds, be sure to include interval training into your routine.