Saturday, April 25, 2009

The Science of Weight Loss

I have spent a lot of my time thinking about weight loss. My research began several years ago when I found a piece of technology that let us measure metabolic function in the clinic. This tool allows us to identify peak fat metabolism by heart rate, and forms the baseline tool of our in-clinic weight loss program.

The question I asked myself was this: Why do people seem to be unable to lose weight AND keep it off?

The data supported this question with harsh realities such as 8 of 10 people gain 110% of the weight they lose within a year for example.

In reality, it is very simple arithmetic - Eat less and exercise more. But the real questions are how much less? And how much more?

The premise of my research argues for simplicity in weight loss. We know that you can lose weight by going on a diet, and we know that you need to exercise to keep it off (the national weight loss registry supports this assertion even though the number of people who have lost more than 50# and kept it off for more than 5 years is very few.)

But I felt that there was something missing, and in my research, I believe I found the answer!

Ready? Type II muscle selectively atrophies.

This fact is made even more important because Type II muscle is preferential in fat metabolism.

Type II muscle is only produced when MAXIMAL effort is expended. I'll rephrase that, in order to build Type II muscle, you have to exercise at maximal effort because if you do not, you only build Type I muscle. On the other hand, if you do exercise at maximal effort, then you actually build both Type I and Type II muscle.

So my conclusion is that in order to lose weight you need to go on a diet (I believe that a Paleo Diet makes the most sense - i.e. fresh fruit and vegetables along with lean sources of animal protein), AND in order to keep it off, you need to exercise at maximal intensity to stimulate production of Type II muscle.

But in the middle, while eating well (nourishing foods), there is value to sub-maximal exercise that takes advantage of the peak fat metabolism HR data we gather by measuring metabolic output.

For example, I have measured in myself that if I exercise at 140 b/m, I burn 8 Kcal of fat per minute, compared to 130 b/m where I only burn 3 Kcal of fat per minute. So if I row (on the ERG) for an hour at 140 b/m, I have burned 480 Kcal of FAT! And because I sprint for 30 seconds every 10 minutes and for the last minute of my training time, I make Type II muscle, which leads to ongoing fat loss at rest while my body first replenishes the used muscle glycogen, and then runs at a higher RPM (more muscle on board means a higher resting metabolism).

One other consideration is muscle based glycogen. A good hard workout burns up muscle based glycogen as well as liver and heart based glycogen. Post exercise recovery involves replenishing this resource. Regular exercise means that you deplete and replenish in an ongoing manner leading to a revved up metabolism. Since you can only replenish at a defined rate between 5% and 10% an hour depending on your fitness, daily submaximal exercise with intervals to stimulate Type II muscle metabolism leads to this cycle in the most efficient manner.

Weight loss occurs intramuscularly first, then intra-abdominally second and finally sub-cutaneously last. When it does start to occur sub-cutaneously, then it starts at the top of your head and works its way down...so be patient, persistent, disciplined, and consistent.

Eat less and exercise more..now you know!

Neil