There may soon be another element to add to the equation. Topiramate (Topomax) which is currently approved by the FDA as an anti-convulsive and for the treatment of migraine headaches and depression is now apparently being studied for FDA approval as a weight loss drug because of its effectiveness and limited side effects. However, many physicians are now using it off-label for this purpose with considerable sucess.
As the chart at the link above indicates, higher doses and initial weights lead to higher amounts of weight loss, but my own ancecdotal contribution is that regular exercise increases any weight loss impact that the drug may encourage.
The drug is not without side effects, a bitter taste, an increased chance of kidney stones, increased fatigue, and some say slightly reduced cognative ability. However, for some, those needing to lose fat as well as increase muscle mass, the drug may prove to be a real boon, especially those who are very heavy or severly obese.
This is not a suggestion that you run out to your doctor and ask for Topomax if you would like to take off a quick 10 pounds. However, if you have spent your life severly overweight, have been working out to try to loose weight and are discouraged, it might be time to think about talking to your doctor or a specialist about this after doing some online research about the side effects.
You’re getting to the edge of my knowledge here. I’m not an expert and have little in-depth knowledge of the subject. I did some research to find the best way to get back in shape, and I understand basic biology and relatively technical language, but I probably do not fully understand all of the things that pertain to this question since it’s a pretty technical subject.
As far as I understand it, the main benefit you get from increasing your body’s efficiency in using oxygen is an increase in performance, i.e.: you don’t get out of breath going up the stairs anymore, it takes running away from a rabid pit-bull to make you breathe hard. Obviously this is good from a health point of view. In my first post, I was talking about some of the benefits of both types of exercise, regardless of whether or not they were good for weight loss.
You don’t seem to care about health benefits, though, only whether it’s good for losing weight. The answer to your question is, again as far as I understand: no, it is not counter-productive. Converting fats into a form your body can use takes much more oxygen than metabolizing carbohydrates. Anaerobic metabolism will preferentially use carbohydrates because they don’t take as much oxygen to use. So, unless I’m completely confused about the way all this works, better efficiency in using oxygen means that fats will be converted at a higher rate than otherwise. In fact, if you don’t have enough oxygen supplied to run the cycle, fat will not be used at all since your body must use oxygen to convert fat to a usable form.
Research about fat metabolism in relation to VO2 max (volume of oxygen consumption relative to body mass, expressed as a rate) shows that people who are in good shape have higher rates of fat metabolism at a lower percentage of VO2 max than those who have lower levels of fitness. So couch potatoes might have to exercise at a higher rate of intensity than ironman athletes to get the same fat-burning benefits, and they hit the anaerobic wall earlier than trained athletes. Exercising at an intensity beyond VO2 max results in anaerobic metabolism, which doesn’t burn any fat.
People whose muscles are not well conditioned will also become fatigued more quickly due to inefficient oxygen consumption in the working muscles before they fully stress their cardiovascular system. Their heart and lungs don’t get stressed, so that system isn’t pushed as hard to adapt, and oxygen transport is not as efficient. This means that they can’t maintain a high level of intensity for very long, which means they can’t lose fat at as high a rate, relative to a person with a higher fitness level, due to a lower overall time of exercise and intensity.
So, muscles that are efficient at oxygen usage demand more oxygen, burning more fuel and increasing the need for efficient oxygen transport, which makes your heart and lungs work harder and become more efficient, which increases your performance levels, which allows you to exercise for longer and harder, which results in higher rates of fat metabolism.
I’m sure that someone with a better knowledge of the subject will now come and dissect my post, making me look like a complete idiot.
Supposedly, you don’t give your body as much a chance to use up the calories, or something like that, since you’re sleeping and your metabolism is slowed. I’m not sure I buy that or not, but it may be true. From most sources, though, that I’ve read that several (6 or 7) smaller meals during the day is better for you to shed weight. I think the theory is to maintain your metabolism, but it practically works out that it keeps your hunger satiated and you don’t have as much an urge to overeat when mealtime comes.
But what I want to know is this: In the end it doesn’t really matter what you eat or when you eat it, does it? As long as you’re on a reduced calorie diet you should lose weight, right? It’s just that certain foods (like carbs) get processed much faster by your body and lead to a feeling of hunger earlier that other foods? Or do I have this completely wrong? If I’m eating 1500 calories a day, does it really matter (from a weightloss, not nutritional, perspective) whether I’m getting those calories from bread or beef or jugs of corn oil?
What you eat definitely matters. There’s data going back almost 25 years that challenges the notion that a calorie is a calorie. See this and this for a more detailed discussion.
When you eat…there’s some room for questions there. There’s some evidence that 6 or 7 small meals does more to keep you out of starvation mode than the normal 3, but nothing compelling yet.
Thanks, ultrafilter. That’s fascinating. Also interesting to see the breakdown between American and Chinese diets, especially since the BMIs are quite lower for the Chinese who have a 71% carb diet (vs. 42% for Americans). And apparently the figures have been corrected to take activity levels into account.