There are three main systems your body uses to access the energy that allows you to move.

Understanding how these systems work can influence how you train to become better at your chosen sport.

The short-term energy system is primarily used for high-intensity activities. Training this energy system enhances fast and powerful movements. This system requires no oxygen to provide energy to the muscles, and uses the energy stored in the muscles cells.

Because a limited amount of energy can actually be stored, it only lasts about 10 seconds. This, of course, is very effective for 100-metre sprints, but not so great for a 10-kilometre run.

To train this energy system, exercises with fast bursts (less than 10 seconds) of muscle action against high loads are used. These exercises should be performed as fast as possible with maximum effort.

Generally, this training is most effective, when it is done after warm-up, at the beginning of a training session. Athletes performing sports like shot put, high jump or sprints, benefit the most from this type of training.

The intermediate system uses energy for between 20 seconds and two minutes. This system produces energy by breaking down the food supplies in your body without using any oxygen to do it.

Unfortunately this system is quite inefficient, and lots of waste products are produced. Lactic acid is probably the most well-known of these waste products.

If enough lactic acid builds up, it can damage muscle fibres, and cause delayed onset muscle soreness. You know, the soreness that you get two days after a really big workout that makes your legs feel stiff and sore so it is hard to walk?

To properly train your intermediate energy system, your exercise duration should be 30 to 60 seconds with recovery periods in-between. To increase the intensity of the workout over time, increase the number of repetitions, but do not increase the exercise duration, or decrease the duration of the recovery.

Sports that use mostly the intermediate energy system include hockey, soccer, racquet sports, gymnastics, and dance.

The long-term energy system is called the aerobic system. The food that you eat is broken down into components and your body combines these components with oxygen to produce energy over the

long term. The long-term energy system does not produce as much energy as the short-term system, which is why it is hard to sprint through a whole marathon. This is also the system that is the most important for recovery time.

The better the aerobic system the faster your muscles recover from exercise. For aerobic training to be effective, exercises should be performed continuously for a minimum of 15 to 20 minutes at 70-90 percent of maximal heart rate; no less than three times a week.

Sports that use the aerobic system include jogging, long-distance cycling, cross- country skiing, rowing, and long-distance swimming.

Much like a hybrid car, your body uses different sources of energy to go different speeds. Understanding what system is used in your chosen sport can help focus your training and increase your performance, whatever that sport may be.

Rehabilitation in Motion has four Island locations including two in Campbell River: Willow Point, 923-3773; Quinsam (across from SaveOn Foods), 286-9670; Comox Valley, 334-9670; Port Alberni; 723-9675. Ben Chatterson works at the Comox Valley Clinic. Visit www.rehabinmotion.com