Originally Posted by
lastostrogoth
I would have to respectfully disagree. At the time I did the testing I was riding 500 miles a month and was in top shape. What I was doing at that time was trying to see how valuable indoor training was by using a heart rate monitor while training. I found it nearly impossible to even get into an aerobic zone while sitting and spinning with the bike on the trainer. As soon as I stood up my heart rate increased markedly into the aerobic zone. Pro riders and coaches have long preached remaining seated rather than standing since standing uses so much more energy.
Look at Contador, Horner, Shleck, etc, they stand a lot and I'm sure they wouldn't do it if it were inefficient. I guess it varies person-to-person depending on their physiology and have used to standing they are. As gregf83 mentioned, if you don't stand often, many muscles used for standing are unconditioned, and that causes your heart rate to spike. If they are properly conditioned, I doubt there will be a spike.