zwift has been my first exposure to power data. I find it interesting. What normally happens to power on hills in real life? What is the strategy? In Zwift, my power "spikes" on the virtual climbs and I presume the same thing happens in real life. Is the goal to keep power output on a climb in a zone that won't lead to excessive fatigue (i.e. close to your FTP?). I intend to get a power meter for my outdoor bike to see what I'm naturally doing on climbs. What does your power meter tell you about the way you climb?

After you've been riding for a while you'll figure out what power level you can ride at for a particular hill length. Clearly, you can use a higher power for shorter hills and less for longer hills. Sometimes I ride at a steady power and sometimes it will ramp up or down during the climb depending on how I feel.

If the objective is to climb the hill in the minimum amount of time, how high your power will be relative to FTP will depend on the length of time the hill will take to climb. For climbs up to 10 minutes you'll be able to exceed FTP the whole way. In general, the idea is to hold your power steady for the whole climb as that should give best results on a solo climb. Group climbs are a whole 'nother thing. Many riders find they do a little better if they ramp up their power slowly at the start of a climb rather than jumping the power up. It may take a bit for your body to acclimate to the higher output: blood vessels have to open, heart rate has to come up, etc. However once you get to where you think you are operating at optimum power for the length of the climb, you try to hold it steady except maybe come up the last 100 yards and accelerate to get the bike moving before the descent. Or not.

On climbs with "stairsteps," it may be advantageous to do over/unders: over FTP on the steep bits, under FTP on the lesser gradients. However I'm not sure that works better for most of us, for whom wind resistance on a climb is not a factor.

For me, power on hills does not necessarily spike. It depends on how much I've been working on the flats. I can put out the same power on flats, on not-too-steep climbs (up to say 13-15% grades), or on gradual 1-3% descents. On hills, my power tends to fluctuate less than on flats but that's the only inevitable difference. If I'm on a group ride drafting before the climb, or just noodling around, yes my power would increase on the climb. But if I'm riding a 20 min TT interval with a specfic power target and start on the flats but finish on a climb, my power might have stayed exactly the same. It depends on what you're doing.

I sometimes use the power meter to pace a climb, particularly if I have a bunch of climbs on that day's ride. If I have say 10 miles of climbing, I'd ride it at or a little above FTP. If I have 50 miles of climbing, I'd pace the climbs probably about 85% FTP. Maybe 90% if the day is cool and the non-climbing parts of the ride are easy.

Sometimes I will do interval work up hills, it's a little easier to make high power targets on hills.

I would not say that my power meters tell me how to climb as much as they are useful in general for pacing- climbs, flats, wherever. But I don't bother trying to pace a two hour fun ride. Just serious things like training rides or races or ultra events.

I was shocked at the power variations when I first started doing group rides in '95. On my solo rides, I was accustomed to maintaining an even power on flats and hills. But these guys were nuts! They'd charge up the hills and dawdle on the flats, or so it seemed to me. This first group ride was a metric double, BTW.

I figured these guys were idiots and would wear themselves out pronto, so I dropped off on the next climb and then held that effort through the coming descent and flat. But they were gone. I didn't see them again until the lunch stop. It's all about wind resistance being proportional to the square of the speed. Climbs reward effort, flats don't.

Unless you're riding solo events like TTs.

It was not inherently obvious to me that OP was referring to group rides, but he/she mentioned Zwift so probably the question does pertain to group rides.

I guess the way I look at it is this: I know my threshold and what power I can sustain and for how long. Can I ride someone else's pace uphill if I'm over threshold? Sure. It just depends on how far above & how long I have to do it. Whether I do that depends on what else I need to get done that day. Double metric and the boys are climbing at 120% of my FTP? Let them go, because that's going to create too huge of a debt for me, no way can I hang on to that group later in the ride. 100% FTP? That's a different matter entirely, might be worth hanging because I know I can put out that power for a long time, especially if I'm getting periods of rest in between efforts.

I understand what you're saying about hills, though, and it does pertain to group ride settings where the people you're riding with are climbing at a pace that's within reach for you.

I think also to TTs, if there's a significant grade. IIRC they've done tests and found that you're better off going a little over/under even if there's just one climb because of the wind resistance thing. Ask your coach.

You are seeing basic racing. Racing isn't done for time or average speed. The goal is simple. Be the first rider of the lead group. If you have a strength, you apply it and if you do it well, you lose riders who cannot match it. The rest of the time, you ride to survive and conserve your reserves at whatever pace is dictated by someone else. And, as you point out, the hills are where a lot of the sorting happens because there is little drafting.

Ben

Totally, your splits will be much more uneven if one portion of the TT contains a hill. We have one course like that in the series I'm doing, it's very tricky to pace.

But I guess I would not describe the power as "spiking" on the climb. My best split on that course right now would probably be 106% FTP uphill and 100% FTP on the descent/rollers that follow. A bigger split would be better but climbing on the TT bike engages an entirely different set of muscles for me, it's very hard for to maintain 110% uphill in aero on that bike with the total amt of training time I've had on hills to date. Out of aero I can maintain 110ish%, so I'll probably finesse my way up in and out of aero depending on speed. If I can eke out an overall 107-108% first half uphill effort and not dig myself a huge hole for the second half, I'll probably wind up with a PB.