Outdoor training without a PM

Your post reminded me that I would never bother fitting a power meter to my MTB. When I’m riding singletrack for fun I don’t care about power numbers and they would be all over the place anyway. But when training on the road I find power data invaluable, especially when pacing intervals, long climbs, TTs etc.


If you had a power meter, your coach instructions would include wattage instructions.

I beat him to that. The thing is, that the average is a good estimate, on a round trip without changing weather conditions.

But it doesn’t take those conditions - primarily wind - into account. If you’re speeding at 50+ kph with a strong tail wind, the power estimate will be through the roof.

That same stretch on the return, fighting into a headwind, will estimate a ridiculously low average.

Following a training plan, with target watts intervals, is impossible.

DC Rainmaker writes in his review (old model from 2016) (https://www.dcrainmaker.com/2016/03/powerpod-depth-review.html):
I’d sum it up as: If you do a clean calibration ride – things are impressively accurate across a wide range of riding environments and positions
Which is good enough for me, when comparing prices of Powerpad with others. But if you have the money, of course the other types are slightly better.

Validation of PMs over RPE and HR for pacing and training outdoors from a new Dylan Johnson video: https://youtu.be/tz3clPpq9Y0

Powerpod looks like an interesting option, especially for a TT setup with aero drag data. I considered one myself, but pricing in the UK is very similar to a single sided crank pm. So I chose the latter for more direct power measurement.

Yeah, that’s my point, re price compared to single sided crank pm. It’s quite close in price.

Crank arms aren’t that hard to swap between bikes as well!

I’m a bit ocd with equipment and like things to be cross compatible where it makes sense ie cranks, wheels, cassettes, etc. So prefer to have Shimano cranks on my bikes.

You don’t know how accurate the total power is with single side measurement. Your legs are more or less different strong.

That doesn’t really affect training at all. You also don’t usually train to even things out.

So… Non issue. Also accuracy has been vetted and your outside and inside power can be consistent.

Ah - interesting. I ride MTB and actually don’t pay attention to power at all outdoors so that is good to know for when I think about doing more road riding.

Interestingly it can, but less so on The Sufferfest. I have a left leg bias, but this evens out under higher load (ie MAP type efforts). If you had workouts based on a percentage of FTP, for me it would over estimate my FTP (due to left side bias) and make VO2/MAP efforts too hard. I guess this is less of a problem with Suf as it’s not based on FTP but 4DP.

Depends what other power measurement sources you have to reference from. I have a single-sided crank power meter on my road bike and my indoor trainer (Elite Direto X) has its own optical power meter. On the trainer I log both power sources simultaneously and they consistently agree to within 2% average over hundreds of rides. My crank power meter tends to read fractionally higher, which could be due to either a very slight left leg bias (I am left footed) or simply the drivetrain efficiency losses from crank to rear hub. Regardless, it’s pretty consistent and plenty close enough for my needs. For example I did a monster 5.5 hr indoor session a few weeks back and average power over the entire ride was identical on both power meters. When both sensors are freshly calibrated I very rarely see more than a 5W difference between them and the very worst difference I’ve ever seen was 10W and it’s always the crank power that reads a bit higher, never the trainer.

Interestingly the only time I ever notice I’ve got a single-sided power meter is when doing single leg drills and then it’s obvious in the data which leg I’m focusing on!


I am trying to figure out which Heart Rate value to use when I train outdoor since I don’t have a Power Meter. I have completed the Full Frontal last week. My new HR values

Max HR is 180
LTHR is 168

When a outdoor work out say:
Effort: 8 minutes @ RPE 6 – 80% of FTP – HR <90%
Recovery: 12 minutes @ RPE 2.5 – 55% of FTP – HR <75%

Do I use my Max HR or LTHR HR to set the heart rate for the workout.
Max HR would be 162bpm
LTHR would be 151bpm
That is a big difference on effort between the two HR.

Any help would be greatly appreciated !

I dumped my bike computer, cadence meter, power meter etc a couple of years ago for outdoor riding. I found I was focusing more on the data than enjoying the ride. Now when I need info I simply say “Dave, how far have we gone?” or “Dave, how fast have we been going?” My riding buddy Dave loves data and Dave gives me the info I need and I don’t miss not knowing my power or cadence. For me that’s only an indoor Sufferfest thing.


I would need to know what the purpose of the interval was and how many you needed to complete. 90% of your LT (he of 150-154 ish) is a pace you should be able to hold for 20 minutes with a 5-10 minute rest and repeat 1 or 2 times. It is tempo work, like the cobbler. It doesn’t hurt at first, but on a 2 hour ride with 60 minutes of tempo in the middle, you’ll be happy to soft pedal the last few miles home. If you are doing a series of 4-6, 8 minute intervals, I would expect you would be working harder with longer relative recovery - a hr of 157-161 or 161-164 with 6-8 minute recovery (recovery = interval instead of recovery of 1/2 or less of interval) For more info, Chris Carmichael (one of Lance Armstrong’s coaches) has a book that is really cheap used or Kindle - $4-7 and explains how to use hr instead of/with power (in 2003 fewer power meters were out there). He defines power and heart rate zone workouts with more zones and narrower ranges, so workout structures are a little different from most others, but his workout descriptions are useful and match well with many Suf workouts. Carmichael may have abetted Armstrong’s doping, but his workouts are still solid.
Of course, Sir Mac and Sir Neal would be able to answer better, They are the professionals.

@cbaum67 When I click on LTHR in the app there is a note that says that to establish your HR zones SUF uses LTHR so I believe that the percentages refer to LTHR. It is a good question and I am glad you asked as I have a few rides coming up in my next plan that are structured that way.

Yes it uses LTHR. You’ll notice some workouts mention HR > 100% because of this.

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