Body Story

• Training the muscles to consume fat

• A virtuous circle

Sadly, there are no miracle cures when it comes to getting rid of fat, unless you count liposuction, which is expensive and may leave scarring. To win the war on fat, the body has to put in the hours. Hours on the treadmill, cycling round the park, or doing Ashtanga yoga in an overheated room.

Exercise works as a weight-shedding tool because the person who wishes to lose fat will be working with, rather than against, his or her brain and body.

Someone who has not done any physical exercise for a long time has allowed their muscles to lapse into disuse. The blood supply to the muscle fibres has withered. As soon as the muscles are used again, they demand energy. But because of the poor blood supply, very little fat can be delivered to the muscles through the bloodstream. Instead, the body uses up fast-burning glucose stores located within the muscle cells.

• Training the muscles to consume fat
Vigorous exercise, however, demands more energy than can be provided just by burning glucose. So once the body is again at rest, it will start to prepare itself for the next bout of exercise, ensuring that, the next time, it will be better equipped to cope with the energy the muscles demand. New blood vessels grow within the muscle fibre, ensuring that greater quantities of fat, which is so rich in energy, can be delivered to the muscles through the bloodstream. Within the muscle cells themselves, mitochondria divide, doubling the energy that they will be able to generate.

If regular and vigorous exercise continues, the body will gradually start to give up its fat stores. The exerciser will need to raise his or her heart rate to around 60-80% of its theoretical maximum for about 40 minutes, at least three or four times a week, in order to make a real impact on fat reserves.

• A virtuous circle
Unlike in a dieting situation, the body does not try to protect its fat reserves as a result of exercise, since it is still getting its normal intake of fuel through food. Eventually, fat will be moved to areas where it is most needed: mini-stockpiles will be created within the muscles. It will no longer just sit, uselessly, around the stomach and hips.

Meanwhile, the muscles become increasingly efficient. They are able to deliver fat more quickly and in greater quantities, which in turn means that the body has more energy, so that longer periods of exercise become possible. The exerciser is caught in a virtuous circle.

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