stem length

i have a 120mm stem on my new bike, which stretches me out slightly more by at least 30mm more than my old bike. can having your arms too stretched forward effect performance? . i don't seem to get as much power in the legs being stretched forward as i did before when i was more upright and elbows were closer to me or is it all in my head.
anyone elase found this?

My experience is that if you are not comfortable, performance suffers. As always get someone with experience to look at your set up and youy may need a shorter stem.

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Dope,when training and talent just aren't enough.

The professionals go into wind tunnels to answer the question of eficiency.

I recall reading that Lance and others have to balance the strength with wind resistance in order to find the best balance.

My interpretation is that somewhere between "maximum power" and "minimum wind resistance" is the true sweet spot for performance cycling.

But for me, I add a vote for comfort. Unless you race, in which case do whatever you need to do.