Originally Posted by
jrennie
TT's and most importantly drinking during them is a very personal thing. I drink a bottle while warming up and heading to the line but don't drink anything during a 40k. Lots of time is lost by reaching down and also the drag of the bottle its self.
Bottle drag is definitely there, a Botrager aero bottle will set you back a couple of watts at 0 degrees yaw (the wind straight on) on a P3. That goes up in a crosswind. More if it's round. Supposedly MIT found some frames were faster with a bottle but I didn't see that in my case.
For me I can't make a 40km without drinking. If you're going to drink practice on the bike, if you're using a Bontrager or other aero bottle buy some stair grip tape and put it on the bottle. If you're sweaty they are slick and easily dropped.
A good TT position will require adaptation. If you're serious and really want to improve, be on the TT bike twice a week at minimum.