Dear Jellybean,
Ok I have a question for you. When you go for a run/jog what does it do for you? Like where does it make muscle and burn fat? Also what does roller blading and bike riding do?
Thanks
-Ashlee
Dear Ashlee,
Running, jogging, roller blading and bicycle riding are all classified as "aerobic" activities. That is, they improve your body's use of oxygen, by getting the heart pumping faster, which raises your metabolism, and burns calories and fat.
Doing aerobic exercise on a regular basis has many benefits, including making your heart stronger and more efficient. Regular exercisers tend to have higher energy levels, more stamina, better concentration skills, and even clearer skin than people who don't work out consistently.
The number of calories you burn (and how much muscle you build) during any exercise depends upon your weight, the activity your are doing and the intensity level you are exercising at. Any activity that you perform can be done at a variety of intensity levels. If you exercise at a higher intensity level, you will be working harder, expending more energy, and burning more calories/building more muscle than someone who is not working quite so hard.
When you burn fat, you generally burn it allover - that is, from all parts of your body. That's why you'll often hear people say that it's impossible to "spot reduce", because you can't burn fat from just one area. (It's also why girls who lose weight often see their bra size go down. When you lose weight from other areas of your body, you usually lose some in your breasts too, as they're made of fatty tissue).
You'll burn a different amount of calories (and therefore fat) with various types of aerobic exercise. In general, here's what an "averagely fit" 120-pound woman would burn during a 30-minute session of these exercises:
Jogging (moderate intensity): 280 calories
Running (high intensity): 340 calories
Roller blading (moderate intensity): 170 calories
Bicycle riding (moderate intensity): 110 calories
Aerobic exercise is also good for improving all-over muscle tone, but where you build muscle will depend on the exercise, and what muscle groups it makes you use. For instance, all of the exercises you mentioned (jogging/running, roller blading and cycling) are mainly lower-body exercises. They're pretty similar in what they'll do for your body. You're using your legs, and your butt, to keep yourself going in all of these workouts, so that's where you'll see the most muscle building.
You can tweak your workouts to focus on different muscle groups, if that's what you're after. For instance, if you're irritated by your skinny upper arms, you might want to do an aerobic activity that puts them to work, as well as using your lower body. Some good ones are rowing, swimming and volleyball.
If it's a tighter tummy you're after, you'll need to either do an aerobics routine that's geared towards strenghening the core (torso) muscles, such as power yoga or a belly aerobics class, or add tummy crunches to your existing aerobic routine.
