Pete aksed: Someone on this post once wrote that exercise helps you lose weight by increasing the breathing rate, which burns calories. Is this so? I always thought an increased heart rate is what burns calories, and the increased breathing rate is a by-product of fatigue. Or am I wrong? Can I burn calories by sitting at my computer and breathing heavily?
Technically, yes, if you don’t eat anything either.
Increased breathing is an effect of fuel burning, not a cause (a significant cause, that is). Real exercise creates a demand for more fuel-burning, which uses up O[sub]2[/sub] and releases CO[sub]2[/sub]. The increased CO[sub]2[/sub] causes the diaphragm to work the lungs faster to eliminate the CO[sub]2[/sub] and get more O[sub]2[/sub].
Since living itself is an exothermic (heat-making) process, you must burn fuel to live. And forcing your diaphragm to move faster is a lame form of exercise and thus burns fuel slightly faster. But faster breathing is hard to maintain if your blood doesn’t need faster gas exchange.
The best solution: exercise for real. Walking just 30 minutes a day (constantly, not up & down office jaunts to the coffee machine) is a minimal but effective way to start an exercise program.