Can we talk about power?

[Harry Meatmotor]

@TwoWheelsDC 119640 wrote:

Now that I have a power meter, I want to get better at using it. I’ve done lots of Googling, but I trust you all more.

Last week, for shits and gigs, I did a couple of 8-minute FTP loops at HP, which gave me an FTP of like 175W (with -10% adjustment). Now this was the day after I’d done a pretty intense hill ride, so I’m not surprised it was low. But today I did a 2 hour hill ride and TrainingPeaks says my Normalized Power was 261W(Strava gives me a weighted average of 230w). For this same ride, I had a 20 minute peak average of 222W and a 10 minute average peak of 265W. So going off the 20 minute power, I’d think that my FTP must be more like 215W, but if my NP was so much higher, I wonder if 215W might even be a little low. Obviously, the best way to check is to do a proper test, but it’s difficult for me to get all the way down to Fort Hunt right now (my rides need to be relatively close to home, for the near future and HP is too short for 20 minute tests), so humor me!

Also, once I have a good idea of my FTP, how do I use for figuring out pacing for rides longer than an hour?

One thing that helps tremendously if you do get a chance to do a “real” FTP test at Fort Hunt (or any other flat, few-turns type course) is to have another stronger rider that’s also riding with power for you to chase. Having a rider about 100m ahead definitely helps keep you at your limits in a way that will get you FTP numbers that are much more honest and less about what’s mentally holding you back. Also, it helps to have some target numbers (i.e., a low-ish bound on what you think your FTP might be) that you’ll want to stay above while doing a “real” FTP test. Going blind is REALLY tough; most blind FTP tests result in blowing up at around 8-12 minutes in. Gauging NP, or back figuring FTP from a hill ride is going to give you funky numbers. Your effort really needs to be as broad and flat as possible, not peaky like a multiple-hill type effort will give you.

One last thought, too, is that much like an individual time trial-ish kind of endeavor, you’re going to want to start easy-ish (and for a 20 minute FTP test) keep increasing your effort by 10-15 watts every 2 minutes. Try and keep a really steady tempo; think, “a little harder, but in control,” or if you’ve got a training buddy, they should be yelling at you “GIVE ME TEN MORE WATTS!!!” every 2 minutes. You’re going to want to kill them by the end, but that’s the point. You should be finishing near threshold or slightly above threshold and creeping into V02 in the last 4-6 minutes.

Once you know your FTP, you can focus on different training strategies to target your weaknesses and train to peak at specific times during the season. That’s really what training with power is all about. Train to your weakness, race (or ride) to your strength. As for rides longer than an hour, based on your FTP, zone 2 is going to be your target – you should be able to ride Z2 for hours on end, with some extra Z3/Tempo sprinkled throughout. Getting into Z4/Threshold is where you’ll start to burn matches you can’t recover from on a longer 2+ hour ride. It’s been my experience that, although I don’t ride with power now, knowing what my zones are based on feel (from having trained with power over the winter), doing the whole power thing is more about conserving watts than burning watts. Sure, it’s awesome to see the “W” on your Garmin hit 4 digits, but that quickly looses it’s novelty when you’re actually trying to do some structured training. If you haven’t picked up Joe Friels “The Cyclist’s Training Bible,” do it NOW.

[hozn]

Great advice from HM (thanks!).

The only thing I was gonna add was that if you can’t find time to get to a place where you can do a CP20, there’s always the trainer. If you don’t have a trainer, I’m happy to lend you mine. You can even borrow my Rubber Glove Sufferfest video I’m sure that Harry is right that having someone to chase would make a lot of difference, but if you just want something to set a baseline for comparison, the trainer would work. Of course, it’s going to be most valuable for gauging progress, and maybe a little less valuable at accurately determining your zones for racing, but I suspect it’ll be within a tolerable margin — at least, my one FTP test produced results that have demonstrated themselves to be useful for pacing in rides/races.

(It does sound like your 8-minute test was not a very good one, though, if you’re doing longer rides with average power greater than your measured FTP.)

My use of power to date is mostly just in the “data gathering” phase. Help understand efforts, help with pacing on the long rides, but not really using it for very targeted training. My goal for 2016 is to use power data for structured workouts. I’ve found it tricky to adopt a training plan while sticking with a relatively steady commuting routine; I need to learn more about training in general to hopefully do that more effectively. (Rest is the hard part; I can certainly have easy days, but can’t fully disengage and soft pedal 15 miles and still make it to work/home on time.) And I’m not really willing to give up bike commuting in order to pursue my racing “career”.

[vvill]

You can also get “Training and Racing with a Power Meter” – a super boring read, unless you’re interested in power and cycling. Even then it reads like a freaking textbook. But it covers all the basics.

I don’t look at weighted power numbers too much. The numbers will give you an indication of how variable your ride was, but average power is more useful for showing what you’ve actually put out (also – in theory, you include 0s on your ride when it comes to average power, but don’t include 0s for average cadence). The weighted power methods/formulas vary – there’s NP, xPower, and Strava’s weighted power as well. You can compare them across rides, but not really with each other.

I would go back to HP on a geared bike (I suspect your FG may limit what you’re putting out in the context of an FTP test). You can use the hills ride number (222W) as a guide for 20 minutes, and as mentioned above start off maybe a little lower, around 210W and see if you can up it after a few minutes. I can never hit the same numbers on flat terrain as on hills though (and I hate doing 10 min+ steady-state efforts/FTP tests!)

Generally for pacing yourself, I would look at your critical power graph after you’ve accumulated a good amount of ride data (including short intense rides, longer rides, etc.). I can’t sustain 200W+ for hours and hours on end, even if my power curve indicates that I maybe should be able to.

And during the course of a longer ride, for short sections where I want to go as hard as I can I generally take around 85-95% of my all-time best as a baseline goal for a specific duration. So for a 5 minute effort if my effort was 300W I’d start out going at 255-285W and ramp up a little if I can.

[Vicegrip]

Second the trainer test advice. Way less variables to deal with. I am right around the corner from you and have a Kurt trainer and dual box fan setup you can borrow. Trainer road suffer fest combo makes the testing part easy to do/control. All you need to do is follow the directions and pedal until you almost puke

[Harry Meatmotor]

@hozn 119661 wrote:

Great advice from HM (thanks!).

The only thing I was gonna add was that if you can’t find time to get to a place where you can do a CP20, there’s always the trainer. If you don’t have a trainer, I’m happy to lend you mine. You can even borrow my Rubber Glove Sufferfest video I’m sure that Harry is right that having someone to chase would make a lot of difference, but if you just want something to set a baseline for comparison, the trainer would work. Of course, it’s going to be most valuable for gauging progress, and maybe a little less valuable at accurately determining your zones for racing, but I suspect it’ll be within a tolerable margin — at least, my one FTP test produced results that have demonstrated themselves to be useful for pacing in rides/races.

(It does sound like your 8-minute test was not a very good one, though, if you’re longer rides with average power greater than your measured FTP.)

My use of power to date is mostly just in the “data gathering” phase. Help understand efforts, help with pacing on the long rides, but not really using it for very targeted training. My goal for 2016 is to use power data for structured workouts. I’ve found it tricky to adopt a training plan while sticking with a relatively steady commuting routine; I need to learn more about training in general to hopefully do that more effectively. (Rest is the hard part; I can certainly have easy days, but can’t fully disengage and soft pedal 15 miles and still make it to work/home on time.) And I’m not really willing to give up bike commuting in order to pursue my racing “career”.

FTP tests on a trainer will *usually* give you low numbers – there’s a fair amount of mental stuff that creeps into a 20 minute solo trainer test that usually flubs your effort. I’ve been told that trainer-based FTP numbers are about 10-20% below on-the-road FTP numbers. That “feels” about right to me, too. My Z2 on the trainer over the winter was about 190W-220W, but out on the road riding with similarly capable riders, I had no problem going for hours @ a guesstimated 230W-250W. On-the-road Z3/tempo feels good around 265-275W. FWIW, my last FTP test put me around 255W (on a warm drum calibrated compu-trainer), so that does “feel” a little low compared to what I know I’m capable of outdoors…

As far as rest goes, I’ve heard it put this way: a good training plan should be as focused on when you shouldn’t be on a bike as what you do on the bike.

[hozn]

That seems about right to me, though my trainer-measured FTP test seems closer to current abilities. I don’t have enough data points to know for sure, but I know from a couple weeks back that I can average (not NP) 220W for 5+ hours which seems compatible with my FTP-based Z2 range of 175-235. I don’t think I could average 250w for hours; 220 was pretty intense. (It also served to underscore the importance of conserving watts — having better/more aero bike posture — as everyone else on the ride had lower avg power numbers.) I have no idea how/when to use NP vs. a straight up average, though, so I might be doing this all wrong. Likely!

[Tim Kelley]

@Harry Meatmotor 119664 wrote:

FTP tests on a trainer will *usually* give you low numbers – there’s a fair amount of mental stuff that creeps into a 20 minute solo trainer test that usually flubs your effort./QUOTE]

Agreed. On the trainer, the bike being in a fixed position and not moving underneath makes for a slightly unnatural feeling and is a limiter. Also, when you are riding outdoors you have air blowing at you at 20+ mph cooling you off. You don’t get that on the trainer, even with a big fan. Heat makes a huge difference in your power output. And just something to think about–some people test better than others because they can mental suffer better, and if you get a true number there may be times where you aren’t able to hit your interval numbers in training later.

TwoWheels–I think 175 watts is very low for someone of your size and riding experience. Even 215 might be kind of low.

After you determine your FTP–you can use a calculator to figure out your zones: http://mtbcoach.com/index.php/training-sessions/zone-calculator/

Z1 is recovery
Z2 is ride all day effort
Z3 is pushing comfortably hard
z4 is riding right at the edge
z5a is beyond your comfort zone and unlikely to hold for a significant amount of time
Z5b – on a breakaway coming in to the finish in the last 1k or trying to catch a jump when it goes
Z5c – sprinting as hard as you can for the last 200m

Once you know your zones you can figure out how hard you can (or should) be pushing for however long your ride/race is. I know that when my FTP is at somewhere between 350-375, I can hold that for a 40K time trial, or that I can ride at 210 watts for more than 10 hours (like during Total200 or riding to the ride for Diabolical Double). If I am doing specific workouts, I can do 2x20s at SST, which is 88%-92% or I can do 105% – 110% for 5-8 minutes if I’m feeling more feisty!

[TwoWheelsDC]

@Tim Kelley 119685 wrote:

TwoWheels–I think 175 watts is very low for someone of your size and riding experience. Even 215 might be kind of low.

After you determine your FTP–you can use a calculator to figure out your zones: http://mtbcoach.com/index.php/training-sessions/zone-calculator/

Z1 is recovery
Z2 is ride all day effort
Z3 is pushing comfortably hard
z4 is riding right at the edge
z5a is beyond your comfort zone and unlikely to hold for a significant amount of time
Z5b – on a breakaway coming in to the finish in the last 1k or trying to catch a jump when it goes
Z5c – sprinting as hard as you can for the last 200m

Once you know your zones you can figure out how hard you can (or should) be pushing for however long your ride/race is. I know that when my FTP is at somewhere between 350-375, I can hold that for a 40K time trial, or that I can ride at 210 watts for more than 10 hours (like during Total200 or riding to the ride for Diabolical Double). If I am doing specific workouts, I can do 2x20s at SST, which is 88%-92% or I can do 105% – 110% for 5-8 minutes if I’m feeling more feisty!

Yeah, maybe I’ll get a trainer this winter, but I can’t stomach the idea of riding stationary for any amount of time. I did think 175 was way low, although I haven’t been riding much this summer, but I don’t really have a sense of where I should be. Having tried a couple of times at HP, and now having a bit more detailed breakdown of my efforts from TP, I think I can probably do a more effective 8 or 20 minute test. Last time, I just used my HR to gauge, but it turned out I could maintain 180bpm (which I’ve estimated to be close to the top of my anaerobic zone, based on my max HR of about 195) for longer than I thought. Although that may be a good benchmark for a 20 minute effort.

Also, I just looked at my calendar, and I think I will be able to get down to Ft. Hunt, maybe tomorrow morning. I just have to make sure I do extra schoolwork tonight.

Do you think the little downhill section on the backside of Ft. Hunt is problematic, or is it just a matter of upshifting and keep hammering?

[Tim Kelley]

@TwoWheelsDC 119694 wrote:

Yeah, maybe I’ll get a trainer this winter, but I can’t stomach the idea of riding stationary for any amount of time. I did think 175 was way low, although I haven’t been riding much this summer, but I don’t really have a sense of where I should be. Having tried a couple of times at HP, and now having a bit more detailed breakdown of my efforts from TP, I think I can probably do a more effective 8 or 20 minute test. Last time, I just used my HR to gauge, but it turned out I could maintain 180bpm (which I’ve estimated to be close to the top of my anaerobic zone, based on my max HR of about 195) for longer than I thought. Although that may be a good benchmark for a 20 minute effort.

Also, I just looked at my calendar, and I think I will be able to get down to Ft. Hunt, maybe tomorrow morning. I just have to make sure I do extra schoolwork tonight.

Do you think the little downhill section on the backside of Ft. Hunt is problematic, or is it just a matter of upshifting and keep hammering?

Please share the data from your tests when you do them.

No, the little downhill section on the backside of Ft Hunt is not noticeable. Maybe would require one small shift adjustment–or you can just pedal harder/faster…

[vvill]

@TwoWheelsDC 119694 wrote:

Yeah, maybe I’ll get a trainer this winter, but I can’t stomach the idea of riding stationary for any amount of time. I did think 175 was way low, although I haven’t been riding much this summer, but I don’t really have a sense of where I should be. Having tried a couple of times at HP, and now having a bit more detailed breakdown of my efforts from TP, I think I can probably do a more effective 8 or 20 minute test. Last time, I just used my HR to gauge, but it turned out I could maintain 180bpm (which I’ve estimated to be close to the top of my anaerobic zone, based on my max HR of about 195) for longer than I thought. Although that may be a good benchmark for a 20 minute effort.

Zwift, or organized group trainer rides (some of the shops around here do them), makes indoor trainer rides soooo much better. I do think if you really want the most precise training, trainers are the best since so many variables are eliminated. I always get better workouts than outside – if I can stay onboard long enough. But I typically only use my trainer when I literally cannot ride any other way.

It did take me some time to realize how often I was coasting (or not putting out much power) on my rides until I got a power meter. And it’s quite easy to spin on a FG whilst putting out 0 measured Watts.

[TwoWheelsDC]

@vvill 119726 wrote:

It did take me some time to realize how often I was coasting (or not putting out much power) on my rides until I got a power meter. And it’s quite easy to spin on a FG whilst putting out 0 measured Watts.

What I would like to know is if the caloric algorithms take HR into account, thus compensating for the zero-power reading…because while I may not be putting down power, my body is still burning a decent amount of calories.

[hozn]

@TwoWheelsDC 119731 wrote:

What I would like to know is if the caloric algorithms take HR into account, thus compensating for the zero-power reading…because while I may not be putting down power, my body is still burning a decent amount of calories.

I think the algorithms that convert watts to calories look at average power, which kinda works out. I am sure some are also more complex.

[Tim Kelley]

@TwoWheelsDC 119731 wrote:

What I would like to know is if the caloric algorithms take HR into account, thus compensating for the zero-power reading…because while I may not be putting down power, my body is still burning a decent amount of calories.

Probably not–if you have power on a ride, it’s not going to us HR to calculate calories, it’s only going to take into account total kilojoules produced.

https://strava.zendesk.com/entries/20959327-Calorie-Calculation

In the same way, if you did a long ride, it would only take into account the amount of energy you burned while pedaling–it wouldn’t take into account your basal metabolic rate. On a 10 hour ride you’d burn a more than negligible amount of calories just “living” (breathing, beating your heart, digestion, and all the other regular bodily functions)

[TwoWheelsDC]

Ugh. 20 minute test was a bit of a bust. While I was certainly tired after the test, I wasn’t falling-off-the-bike tired or about to hurl…more like “ugh, now I gotta ride home” tired. But I did think of a couple important questions. Like, should I be trying to maintain a constant power output, or a constant effort? My HR was pretty consistent throughout the test, but given the Fort Hunt loop, there were places I was doing like 100W, and others where I’d be doing 400W. Should I be holding back during the 400W sections and then hammering to get my power up during the 100W sections? Or do I do like I did and just let them average out?

Also, I learned yet again that I can sit in the anaerobic zone longer than I thought. I was running an HR average of 185 for 20 minutes and wasn’t really feeling like I was hitting the wall. I feel like I could’ve either run at like 190 average HR, or gone for at least another 5 minutes before I crapped out.

[hozn]

I would probably have a hard time if it there were downhill sections/areas for coasting. That is why trainer is nice for this. Or a 20-minute climb.

If it wasn’t a problem with coasting then maybe keep your 3s power average on screen and work to hold it relatively steady. I would just do this on a trainer first; you can’t coast there.

I think your average HR for the 20 minutes is your LTHR, though, so wouldn’t be anaerobic.

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