Power = Energy / time
Energy is measured in Joules
1 Watt = 1 Joule / 1 second
1 Calorie = 4.18 Joules
1 Dietary calorie = 1,000 Calories = 4,180 Joules
Ride at 200 Watts for 1 hour (~20 mph on flat ground) and you'll have *applied*
200 Watts * 60 min / hr * 60 sec / min = 720 kJ
720 kJ / 4.18 kJ / Dietary Calory = 172 D.Cal
however, since the body's mechanical efficiency during cycling is somewhere between 20 and 23%, you actually burn ~800 dietary calories.
incidentally, your body can store ~1500 calories in the form of readily available muscle glycogen to be used at 80-100% of maximum aerobic capacity. beyond that, you've to supplement with PowerBars or Gatorade or Bison Urine or whathaveyou.
...I know that to ride at that rate I would be at ~80% of my anaerobic threshold, consuming 56 mL of O2 per kg of my body weight per minute. I suppose I can calculate my mechanical efficiency from that, but I'm pained to do that at the moment.
now, whatever your pedaling style, it has been scientifically verified that aerobic cycling performance is always limited by the oxygen supply rate. period. if you push harder, more little kinesins are recruited in the muslce fibers, requiring in turn more ATP and more oxygen molecules. if you cardio system can't supply it, the muslce tissue goes rapidly into severe oxygen debt, that is to say, it goes anaerobic, starts producing lactic acid at rates much faster than the body can clear it, and in about 8 seconds that's all she wrote.
if you choose to recruit more muslce groups in your cycling activity, all that means is that more kinesisns are being put to work (it doesn't really matter in which specific muscles they're located, only that more of them are working), requiring more ATP and oxygen. again, the bottleneck happens to be the rate of oxygen supply, which is limited by lung capacity times red blood cell count times hear rate.
...more muscle often means you can store more glycogen though, and bigger muslcels also often allows greater forces to be tolerated, but in the end, you still have to supply oxygen to all that muscle fiber...
read more about this stuff here:
http://www.cptips.com/exphys.htm#oxdebt
Energy is measured in Joules
1 Watt = 1 Joule / 1 second
1 Calorie = 4.18 Joules
1 Dietary calorie = 1,000 Calories = 4,180 Joules
Ride at 200 Watts for 1 hour (~20 mph on flat ground) and you'll have *applied*
200 Watts * 60 min / hr * 60 sec / min = 720 kJ
720 kJ / 4.18 kJ / Dietary Calory = 172 D.Cal
however, since the body's mechanical efficiency during cycling is somewhere between 20 and 23%, you actually burn ~800 dietary calories.
incidentally, your body can store ~1500 calories in the form of readily available muscle glycogen to be used at 80-100% of maximum aerobic capacity. beyond that, you've to supplement with PowerBars or Gatorade or Bison Urine or whathaveyou.
...I know that to ride at that rate I would be at ~80% of my anaerobic threshold, consuming 56 mL of O2 per kg of my body weight per minute. I suppose I can calculate my mechanical efficiency from that, but I'm pained to do that at the moment.
now, whatever your pedaling style, it has been scientifically verified that aerobic cycling performance is always limited by the oxygen supply rate. period. if you push harder, more little kinesins are recruited in the muslce fibers, requiring in turn more ATP and more oxygen molecules. if you cardio system can't supply it, the muslce tissue goes rapidly into severe oxygen debt, that is to say, it goes anaerobic, starts producing lactic acid at rates much faster than the body can clear it, and in about 8 seconds that's all she wrote.
if you choose to recruit more muslce groups in your cycling activity, all that means is that more kinesisns are being put to work (it doesn't really matter in which specific muscles they're located, only that more of them are working), requiring more ATP and oxygen. again, the bottleneck happens to be the rate of oxygen supply, which is limited by lung capacity times red blood cell count times hear rate.
...more muscle often means you can store more glycogen though, and bigger muslcels also often allows greater forces to be tolerated, but in the end, you still have to supply oxygen to all that muscle fiber...
read more about this stuff here:
http://www.cptips.com/exphys.htm#oxdebt