Should I use Normalized Power or Average Power for determining FTP?

[RapDaddyo]

Originally Posted by yeaux .

I started a new thread similar to this (more specific to myself), but I guess it is in moderation to be approved.

Eitherway, I was wondering a couple things based on this thread and another regarding NP:

1. Say a higher-than-FTP 60 minute NP ride comes from repeats of 30 second sprints with resting time or a hard group ride, is this method still valid for increasing FTP?
2. Wouldn't the reliance on NMP and AWC in forming the higher 60 min NP overstate the other training levels? For instance, If one produces a 290+ watt 60 min NP for the above workouts, but the best 20 minute effort one has put out to date is approx. 275 watts, wouldn't setting an FTP level of 290 watts overstate the other "endurance" levels (L2, L3, L4, etc.)?

Thanks for any thoughts or comments - I'm trying to wrap my head around this concept some more and want to make sure TSS isn't overstated too greatly.

A few comments that may help out.

1. FTP is simply the 60min data point on your power-duration curve. Normally, all of the data points on your power-duration curve represent your maximum constant power for the given duration. If you use NP as a proxy for one of these data points, it may or may not be accurate relative to your maximum constant power for the duration. The only time it really matters (see below) is when you are planning your target power for an event in which you have full control of your power (e.g., an individual time trial). For these purposes, it would be best to test your maximum power for the estimated duration of the event (e.g., about 60mins for a 40K ITT on a relatively flat course) with a constant power ride. You can also use the Monod Critical Power Model with 2-3 (I use 3) data points. I use this method, with max constant power test rides at about 3, 8 and 30 minutes. When I say "about" 3, 8 and 30 minutes, that's because of the test protocol I use. I use my trainer and choose a power level that I think I can maintain for approximately the duration target for the test (e.g., 30mins). I then ride at that power until I can no longer maintain the power. I record the exact time and use that in the Monod Critical Power Model. One note of caution about using the Critical Power Model. Max power at durations longer than an hour tend to be overstated. For this reason, I regularly test my 120min MP because that is an important metric for planning most of my target events.
2. For training ride purposes, the recommended targets by level in Andy Coggan's schema is based on a "standard" cyclist's power-duration curve. But, there can be important differences for an individual cyclist, especially for the shorter durations. So, two factors can contribute to a target power for a training ride that is either too high or too low (for you). One potential reason is that your FTP estimate is not a valid estimate (e.g., due to using NP from a highly variable power ride). The second potential reason is that your power-duration curve is not "standard." You will immediately realize that you are either struggling to ride the effort at the target power or that it is too easy. For example, you may find that you cannot complete your second 20min L4 effort at 100% of FTP. This would suggest that your FTP is overstated. Or, you may find that both efforts are simply too easy. This would suggest that your FTP is understated. You should be able to complete both efforts, albeit with high concentration during the second effort.
3. FWIW, I tend to ignore the standard prescription and ride my training efforts at about 90% of my max power for the given duration. So, if I ride a 30min L4 effort, I would choose about 90% of my max 30min power. If I ride a 3min L6 effort, I would choose a power of about 90% of my max 3min power.
4. As to the likelihood that a highly variable power ride of an hour will result in an overstated FTP, I have tested this theory against a whole bunch of ride plans and have found that NP is a good predictor for me. For example, I have done 15sec on/off for an hour, with power targets of say, FTP+100W/FTP-100W. My most extreme such test was 6secs at 600W followed by 24secs at a recovery power. BTW, I can highly recommend this last one as good training for crits. For me at least, NP is a good predictor of my max constant power at most durations of at least 20mins.

 

[yeaux]

Thank you for the comments, both of you. I plan on performing a series of tests in mid-September (work is very busy lately and the wife and I are going on vacation for two weeks) and will post up the results.

RapDaddyo - I think your comments about percentages of max power are interesting. Do you generally find that, by basing your workouts on a % of max power, you tend to still see improvement in those areas? I'm wondering in order to carry the improvements I have made this year through the winter and have considered basing workouts off % of max power in order to do so (a thought that was largely sparked by Dr. Coggan's 90/90/90 workout).

 

[RapDaddyo]

Originally Posted by yeaux . RapDaddyo - I think your comments about percentages of max power are interesting. Do you generally find that, by basing your workouts on a % of max power, you tend to still see improvement in those areas? I'm wondering in order to carry the improvements I have made this year through the winter and have considered basing workouts off % of max power in order to do so (a thought that was largely sparked by Dr. Coggan's 90/90/90 workout).

Yes, I find that riding at 90+% of my max power at all durations results in significant improvements in my MPs. It may seem illogical that you can increase your FTP by never riding at or above FTP, but it's true. One year I rode for several months doing all of my L4 efforts at 275W, under the assumption that my FTP was about 300W. The next time I tested my FTP it was 326W. After that I was forced to bump up my L4 efforts to about 300W. Ugh! One benefit of my approach is that I almost always have a good data point to base my training ride efforts on.

 

[daveryanwyoming]

+1 on basing intervals for nearly all durations on 90% of your recent best MMP for that duration. It works really well for things as short as a minute or less all the way up to hour plus sustained efforts and is self adjusting as long as you don't use the power meter as a hard and fast 'governor' in your training. IOW, start intervals targeting 90% of your recent best MMP for the time but give yourself freedom to really get after it on days where the power flows and you feel great. That's how you'll start seeing higher power numbers on some days and how you'll reset the targets over time. Of course also know that not every day is a record chasing day and the 90% target is still a really good workout so don't feel pressed to chase records every time you train. And when you hit those inevitable days when even 90% of your target isn't going to happen then either replan the workout on the fly for a lower training level or recognize that you need more recovery and spin home.

Pure short sprinting is about the only thing that should really be done 100% flat out maximal effort every time. You never want to train yourself to do mediocre sprints so go all out for them and do them with sufficient rest that you can really nail each effort for maximum acceleration and speed to the line. You won't be looking at your PM and pacing during a full out short sprint anyway but even if you did you wouldn't be targeting 90% of your previous best 5 to 20 second effort you'd want to be going as hard and fast as you could manage for each one.

Approach training something like that and this stuff is self adjusting. As your fitness improves the targets will rise, on normal training days when records aren't likely you'll be getting good solid work and on days when you need more rest you'll get very good and immediate feedback when even 90% of your previous best isn't gonna happen. Those are all parts of training 'with' power instead of chasing hard targets based on previous test days and regulating your efforts via the power meter to stay close to those hard targets regardless of how you feel, that's training 'by' power.

Good luck,
-Dave