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ClockworkOrange
12-06-2006, 01:19 PM
Had a great little Specialized bike computer, probably about 7 years old but unfortunately it is no more.

Bought a great one of ebay, not very expensive and my favourite colour to go with my Orange bike and it is wireless, made by Twins.

But can somebody explain to me about the CALORIES/ FAT BURN (GRAMS) setting. OK, I can follow the calories if it says I have burnt up 650 but am confused about the fat burn?

Cheers.

Sally
Bad JuJu
12-07-2006, 06:36 AM
I don't know the computer you're talking about, but I do know a little bit about fat grams. I've read that if we're trying to lose weight, we should try to consume less than 40 grams of fat per day (less than 60, for men), and probably closer to 20. So maybe your computer is telling you how many fat grams you've burned so you can figure the difference between what you've consumed for the day and what you've burned? Just a thought.
HillSlugger
12-09-2006, 07:09 AM
An exercise bike I've ridden at the gym has a chart of heart rate vs weight and then claims that there's a heart rate zone that optimal for cardiovascular gain and another that's optimal for fat burning. Perhaps your monitor is trying to count time in the different zones?

Do you have the manual for the monitor?
beetle
01-15-2007, 09:26 PM
At different exercise intensities your body uses different percentages of energy from fat and carbohydrate sources. From one of my nutrition books the relationship is roughly: 75% from fat/25% carb @ rest (ie. watching TV), ranging to 0% fat/100% at max exertion and about 30% fat/70% carb at 70% MaxHR.

Your computer is probably using your speed to guess your energy output and HR (or VO2max) to estimate your level of intensity and therefore calculate the appproximate grams of fat you are burning in your session. If the computer is reading your HR it will be more acurate. It is really a pretty crude estimate though as it is highly dependent on your weight and fitness level.

Basically at lower intensity your body uses a higher proportion of fat than carbs BUT you use more calories at higher intensity and even though the prop of fat is lower you will generally burn more fat in higher intensity sessions. Hope that makes sense.