Exercise is important for health. Properly done, it causes an uptick in your basal rest metabolism that lasts beyond the exercise itself. Your body preps itself for continued exertion, repairs all the damage you just did, and builds up new muscle fiber and capillary capacity.
Exercise doesn't necessarily cause weight loss but it does make you leaner than you would have otherwise been. Substituting muscle for fat is a way to fight obesity and won't show up on the scale. That's why BMI is more important than weight. However, BMI charts have been skewed by popular culture, so one shouldn't be strictly married to a number.
I have never found exercise to increase my appetite but rather to act as a suppressant. Weight lifting was good this way but cardiovascular exercise is better. Has to do with hormones and endorphins released during the activity. (Work out hard enough and you get
runner's high.)The endorphins and enhanced blood circulation to the brain are also why exercise is very good for depression. A lot of people report their best thinking is done during a brisk walk.
As to calories burned by exercise... It is true there isn't a lot burned in any one exercise. But say you walk a mile a day on level ground. You might (depending on your weight) burn an additional 100 calories. Do that for 10 days and you've burned 1,000 calories. A pound of human fat tissue varies but is generally 3500 calories, so there goes a significant amount of fat. (It may not all immediately show up on the scale as increases in muscle mass may counteract it.) The many little burns add up to a significant burn over time. After you've done that mile for a few weeks, you'll probably kick it up to a couple of miles or maybe start going uphill. The rate of fat burn will increase.
Walking Calories Calculator by Distance Walked
The interesting thing is that the distance and the elevation gain are what is most important for weight loss. Faster does burn more calories because it is a less efficient mode of travel but not by a vast amount. (My knees won't take jogging so I'm stuck with walking.) OTOH, cardio fitness requires some sweat and breathlessness. Strength conditioning usually means some level of muscular exhaustion.
It is ironic that while the average person is getting fatter, the ideal body seems to be something with 6 pack abs, visible ribs, and high levels of muscular definition. Not an ideal many of us will achieve. It has been drifting that way that since the mid 20th century. Even though BMI has climbed consistently since 1960, lean was not always the aesthetic ideal in the past.
In reality, fat reserves are essential for dealing with stress, injury, and illness. And humans need some fat in their diet for proper nerve development. If you stop eating fat entirely, you will eventually die from it.
Weight loss and gain happen over a long time. If you are looking to lose more than a pound a week either you are morbidly obese or you are trying too hard.
