HMF

PS, from what I've read even the Leanest cyclist has 60,000 to 100,000 calories of fat to use

thehammerdog

The power of the big men......When the Big boys said lets go it was a freak show...Versus is great.
watched most of the race...I rode a nice 12 mile ride aound the lake????

timster

That doesn't sound right.

Let us assume the leanest cyclist is around 5% body fat and weighs 150 lbs. That means he has 7.5 lbs of fat. There are 3,500 calories in a pound of fat. 7.5 * 3,500 = 26,250 calories

And that's if he were to deplete every ounce of fat in his body, in which case he'd probably die. Not to mention the fact that cycling doesn't explicitly burn fat. Lean body mass is lost along with the fat.

Of course, I'm no biologist, so I could have something wrong here.

merlinextraligh

You can set it to record in 1 second intervals. I don't use Garmin Connect, so I don't know what Garmin Connect does with that data. But look at it in Cycling Peaks WKO, and there's data by the second.

gregf83 

The rest of your calculations look OK but the body will use fat in addition to glycogen as a source of energy during normal cycling and not muscle.

gregf83 

That one is equally wrong just in the opposite direction. Unless he has an efficiency of 50% while the rest of the world lives with 18-24%. I think it's best just to ignore Garmin estimates of calories regardless of how they are calculating them.

Shimagnolo

This.

merlinextraligh

True. Average Power of 239 equals 860 KJ. Multiply by 1.1 (which assumes the midrange of that 18-24%) and you get 940 calories an hour, or 2820 for a 3 hour race.

Which is again roughly consistent with around 6000 calories for a 6 hour Paris Roubaix, as opposssed to 10,000.

brn2run

My experience has been that my Edge 500 shows me very similar calories burned
numbers to that of several other calorie counter web sites that I have used
in the past.

I'm not expecting an exact science, just ballpark numbers.

achoo

To be really nit-picky, if that's a Garmin Connect "average power", it's almost certainly overstated.

IME Garmin Connect gives about a 5-10% overestimate on power for a steady-state trainer ride where my power is almost constant, and sometimes a 20-30% "bonus" for rides where power varies wildly, like I suspect it would in a pro race like these. For example, on Sunday I had three-hour ride where Garmin Connect said I averaged 200W but Training Peaks and Golden Cheetah both say about 160W.

clink83

Just because you're carrying body fat doesn't mean all of it is available for use.

Not true. If you starve yourself while riding you're body will burn muscle quite readily.

clink83

Not true.

Shimagnolo

Everything I've read indicates you use glycogen until it is depleted, then transition to burning fat.
This transition is called "bonking".

gregf83 

I don't starve myself while riding so I don't consume my muscles. Maybe you do but most don't find that an effective way to train.

gregf83 

No. The amount of fat oxidized is a function of the intensity of your ride not the duration. At low intensities a higher proportion of energy will come from fat stores.

Shimagnolo

Well, that is ironic.
So you need to keep it down to 65% to get rid of maximum fat.

merlinextraligh

Until you get to the point that you've used up everything but fat, and all you got left is fat. So duration, particulary duration above threshold, comes into at some point.

Thus the reason that you want to stay below threshold as much as possible in a race (i.e. not burn matches) and why raising threshold will let you sprint faster at the end of a race. To the extent you're staying below threshold, you're using more fat, and saving glyogen, i.e. not burning matches.

gregf83 

It depends how long you ride. If you don't have a lot of time you're probably better off riding harder and burning more calories. Provided you don't eat too much your body can replenish it's glycogen stores from your fat after the ride.

merlinextraligh

No. Because you're talking percentages. At 90% efforts, less of the total percentage is coming from fat, but you're putting out more energy overall. Thus you'll still burn more calories with hard interval efforts that putzing around.

That said, becuase you can use fat, and not reqiure a lot of carbs, you can lose weight by eating less and doing long slow rides.

Whereas its hard to do hard interval training without taking in calories to fuel the efforts. Hence why its better to lose weight in the off season and base phase, than in season.

gregf83 

Agree on the first point and the benefits to raising your threshold. Regarding sprinting, I think there are some other mechanisms at play. It's not hard to burn too many matches during a 30 min crit and not have a good sprint even though you still have lots of glycogen available. Sprinting depends on anaerobic capacity which is dependent on more than just glycogen.

merlinextraligh

Yeah my statement is an oversimplification. But having a higher threshold gets you to the sprint stronger, and if you have exhausted your glycogen stores, your not going to be able to go anerobic, much less sprint. So not exhausting muscle glycogen is part of it.

Lithuania

no

hodie21

His power was "HAULING ASS"

trobinson017

ROFLMAO!!!!!

z90

Not according to the graph. Y axis is g/min