For those trying to burn excess fat my advice is to only do lower intensity exercise. That's right, low. If you're tired after you've exercised, you are working too hard.
The body has three sources of energy that it calls upon when exerting movement:
-glycogen: sugar stored in the muscles
-glucose: sugar stored in the blood
-FFA's, or free fatty acids, which come from fatty tissue (via the mitochondria), or triglycerides stored in the body.
Whichever source of energy your body decides to use depends on the intensity in which you're doing exercise. What you want to burn are the FFA's, which calls for low intensity isotonic exercise.
Why is that the case?
There are two types of muscle in the body, Type 1 and Type 2 (technically, type 2 has several subtypes, but we'll ignore that! 8D)
Type 1 consists of red muscle fibres, and Type 2 consists of white. In short terms, red muscle is oxidative (requiring oxygen), slow, and uses fats (and carbs and proteins) as its main source of energy. When that source of energy is depleted, THEN and only THEN will it move onto glycogen.
Type 2, white muscle fibres, are fast and anaerobic (no oxygen) and go straight for the glucose because they need a much more readily available source of energy to maintain high-intensity movement (for a short time).
Marathoners, cyclists, anybody who partakes in endurance exercise will have more of Type 1.
Sprinters, weight lifters, and the like will have more than Type 2.
Bottom line: If you push yourself too hard, you will burn little fat because as soon as you increase in intensities, burning glycogen or perhaps glucose will take priority over burning fats.
How much is enough exercise?
What you want to do is exercise at an intensity at which only 60% of your MHR/HR(max), otherwise Maximum Heart Rate, and not more than that.
Everybody is different. Everybody has different kinds of muscle, bodies, habits, fitness levels, what have you. They're infinite possibilities so that there's no universal way of determining it. Reflective of this are the number of formulae out there.
One is this:
MHR = 220 - (age) = BPM (beats per minute)
Then take 60% of that:
So, say you're 19 for example:
MHR = 220 - 19 = 201
201 BPM x 60% (0.60) = 120.6 (we'll say 121)
So 121 BPM is the ideal heart rate you would want when undertaking any sort of sustained aerobic exercise.
Another MHR formula is
MHR = 205.8 - (0.685 × age)
So
MHR = 205.8 - (0.685 x 19)
MHR = 193 BPM (rounded up
60% of that is 116. So there's a bit of a difference there, but it's not astronomical. There are other formulae out there, so really choose what works best for you.
So remember, if you want to burn fat, go for lower intensity exercises, 15-60 minutes everyday. Every day is ideal, but you never want to leave more than 48 hours between exercise.
Thought I'd just put this up here, don't know if anybody'll find it of any use or not, haha.
