Lose One and Win Another
To burn fat, aerobic exercise must not be of high intensity.
When you exercise too hard or become breathless while
exercising, the energy which feeds your movement, is drawn from
glycogen in your liver and muscles, not your fat stores.
You do not start to burn fat as soon as you begin your work out.
Getting your body to burn fat instead of glycogen depends on
complex hormonal responses (adrenal hormones and insulin) to
trigger your fat cells to release triglycerides into the blood.
In the first 20 minutes of exercise, the body burns sugar from
the glycogen stores. In the next 10 minutes, the body burns a
mixture of sugar and fats. Only after 30 minutes does the body
burn proportionately more fat (50 percent from fat). The key
about fat-burning is to exercise not hard but long.
Studies in exercise physiology show that the minimal aerobic
threshold to shed fat demands continuous movements of at least
30 minutes duration carried out at least 3 times a week. It has
to be continuous and should you stop and restart workout after
20 minutes of exercise, the hormonal shift has reverted to
burning sugar again. For beginners you may find that your
muscles may not sustain exercise tor 30 minutes. It is normal as
it may take several weeks to build up your muscular strength
SLOW DOWN. Many work-out instructors advocate a training heart
rate of 60-70 percent of the maximal heart rate (220 minus your
age). However, at that kind of rate the unfit majority will
reach their anaerobic threshold, and the body will burn mostly
protein and sugar. This is why overweight people are seen
panting excessively while exercising.
In fact, the optimal intensity of exercise for fat burning is
far lower at 50-60 percent of your maximal heart rate. A daily
walk of at least 30 minutes will burn far more fat than killing
yourself at the gym.
Body fat is basically caloric dense. This means that it needs a
lot of oxygen to be metabolized- broken down- so that it can be
put into the bloodstream and used as energy. If your workout is
too intense, the body will not be supplied with enough oxygen
and switch to other tissues for energy. In effect, it will stop
burning your stored fat and increase its burning of protein and
glucose, for these tissues require less oxygen to burn. Exercise
too vigorously-say running or sprinting, and your body never
gets enough oxygen to burn fat efficiently. As long as the
intensity of your exercise increases, the amount of oxygen
available decreases. When this happens, your body has to look
for more sugar and protein to maintain the effort.
Correct nutritional support is important
for athletes and is the difference between winning and losing.
For recreational athletes, nutritional support is important to
prevent injuries, aid recovery and to keep the body optimal for
continued peak physical performance.