> Several myths are revealed in this post. First, the percentage of fat
> burned is irrelevent to weight control. What is important is energy in
> versus energy out. Basal metabolic rate plus calories expended minus
> calories consumed determines the weight gained or lost. Low intensity
> fat burning exercise is a myth.
I would suggest that you go back and read. Being a diabetic, it's worth
my life to understand these things. I'd suggest you look at the
relationship of fat and carb energy supply at various energy output
levels. Then look at the effects of various types of training on those.
I agree that what's important is energy in vs energy out. Unfortunately,
if you train for carbs, you cannot keep going without them, and the
supply is small. So, you have to eat virtually as many calories as you
burn. If you train for fat burning, and you only replace the amount of
calories in the carbs used and your input will be less.
Plus there's a training effect, and long, relatively low intensity
exercise (we are talking 60-70% of max here) does result in better
mobilization and utilization of fat. To get there, you have to use up a
good proportion of your sugar stores before you even get into the
training phase. What this means is that you will need to replace less
carbs as you get in better fat burning shape.
Any exercise burns some fat. The lower the intensity, the greater the
proportion burned. A good compromise for long distance cycling is 60-70%
of your max aerobic output.
> Its a false assumption that a person concerned with weight control or
> health is a "racer". I've never participated in a bike race but I am
> concerned with my health.
That was a separate subject, responding to a undercurrent this thread
has had for some time. If anything, racers may even be less concerned
about their long term health. They are focused on winning, and will make
lots of compromises with their health if they think it will help.
> Most exercise people don't bother with the measurement of calories
> burned because its way to dificult to measure acurately. The various
> tables we all see are usually inaccurate or inaccurate at certain
> levels. Power or Watts is the prefered measurement. Twelve mph is a
> very low level of effort, equivelent to very easy walking. One or two
> hundred calories/hour is a fair estimate for such a minor activity.
Any of these measures are difficult to measure accurately. But, they are
not near as difficult to calculate, at a lower level of confidence, but
still useful for planning purposes. For me, when I calculate my energy
usage and account for the amounts I get in my diabetes control planning,
I come out correct in my *** sugar levels.
Ok, from "Bicycling Science" page 39, figure 2.4, interpreted from the
graph. Crouched Racing cyclist 300 calories/hour at 12 mph; Upright
tourist 450 calories/hour at 12 mph. That, of course is flat riding on
smooth surfaces. Around here, you have to add about 500'/hour climb at
12 mph. To say nothing of wind, rough roads and so on.
Easy walking does work out at about 150 calories/hour, depends on what
you call easy. This also from "Bicycling Science" page 37 Table 2.1.
Comparing what's on the two above, twelve mph equates somewhat on level
ground with walking in excess of 5 mph, hardly easy walking. Though I've
gone nearly that fast with a backpack on my back in the right terrain (downhill).
Use Power, Watts, Calories, they all relate by simple multipliers,
whatever, a non-issue. Actually the program I wrote for my own use gives
me Calories, Calories/min, Watts and Horsepower. All as put into moving
the bike. But, since I use it to plan my diabetes diet and medication, I
pay most attention to Calories.