FKLance said:Ok, you can be fast with a flat back.. I just do not see it as optimal.
If you go with a flat back, you are closing your hips entirely, thus you are only riding with your frontal leg muscles. I think Anquetil is the perfect example: He had the strongest back in the peloton and he was using an egg-position which made possible for him to use all of his powerful middle-body muscles in a hunched back position. How many times he won GP de Nations? 7, 9 times? If you look at Contador riding out of the saddle in the mountains, do you think he is using only his legs? he is using his entire body. I think people with a flat back should be working on the support muscles and their flexibility, and would probably find weaknesses.
I think saddle should be level or even a few mm upwards. Reason for this would be: when you move lower, you should go forward. When you go forward, you should go up because of knee angle.
With an egg-position you do not get any numbness whatsoever because you are sitting correctly on the bike. When you are comfortable, you can produce more power.
The problem with going forward is that it is illegal under UCI rules.Which is why manufacturers who make 2 position seat posts often refer to the forward as the triathlon position.Everyone from the size of Cancellara to Pooley has to ride in the rear position to stay legal.The rules were brought in to outlaw the 2 Obree positions, both of which were very forward.
