Originally Posted by
aliasfox
One thing I've noticed over the past few rides is that I'm more likely to catch up/pass other riders as the road pitches upwards, but strangely enough, have the most trouble keeping pace on flats or slight descents.
The other riders are trying to maintain constant power output which should be the same thing you're supposed to be doing unless you're doing some sort of interval training.
Note, none of these sections are really longer than 3-4 minutes before the road pitches up or down, so I don't think it's a sustained wattage thing, either.
It can be sustained power output if you're going round and round that circuit at constant power for more 15 minutes without stopping. It doesn't matter if the road pitches up or down especially if the gradient is not too big and you can still pedal and apply power on the descents. Training will definitely help in that case.