Heathpack 

Or maybe Strava is assigning TSS for my mtb rides on HR. I could see that being an underestimation because what’s really fatiguing for me on the mtb are the microbursts of power to say get over a rock or root. Those happen for such short bursts of time that they don’t necessarily elevate HR (unless you string together a series of such efforts) so I could see Strava “missing” the stress of these microbursts in the absence of power data, and significantly underestimating the physiologic impact. Especially for someone like me, who is relatively fit (ie resistant to HR elevation) but not strong (so the microburst of effort is proportionately way higher over threshold than your ‘typical’ ie male mountain biker).

I think this explanation makes more sense than the speed idea I floated in my previous post. But regardless, it’s pretty obvious and not something that it’s too hard to get past intellectually, despite the numbers you see calculated by the software.

redlude97

I honestly don't even bother carefully analyzing TSS, as rubiksoval put it above, it isn't all that important as I've trained with power more. What does it really tell you? You trained hard? Your legs kinda tell you that. Your TSB is super negative? You should feel that too. So while the PMC is a good check, small differences in TSS/NP from different algorithms won't substantially make a difference in quantifying training. How you hit the intervals for the day or for the week and how they compare to the following week or following month etc are where the PM is helpful

Seattle Forrest

That's right. Doesn't make sense to me, but it's technically correct per the definitions. It does make sense to count zeros at lights and maybe that's why TSS is based on total time? But it seems like when you stop the clock ... the clock should stop.

This is what "the beer and burrito rule" is about. If you stopped long enough to enjoy those, it's a new ride when you start again. To avoid messing your TSS up.

I do enough non-bike exercise that an HR based training load works better for me than TSS.

Seattle Forrest

I've got a bunch of loops I do where I never leave city limits. Get out into the residential zones where the nice parks are, and the lights aren't every block anymore but still pretty common. I've never counted, and now I'm curious but not enough to actually count them... Over a 3 or 4 hour ride that night not be too far off. They're not all red though.

Carbonfiberboy 

Now that I have a PM for my single, I'll use power for TSS on singles, still using HR for the tandem and everything else. I would think that TSS should approximately equal hrTSS, except be a bit more accurate in terms of kj. As the PMers note, HR at the same effort can vary with exhaustion, hydration, and blood sugar. TSS tells one more about kj, but less about one's physiological state. On my Ohanapecosh ride a few weeks ago, before I had the PM, Strava estimated my power on Cayuse and White passes as exactly the same, though my HR on White was 6 beats higher. OTOH there was a slight headwind on White, so maybe that wasn't all exhaustion. I did leave it all on the road, had to lie down in the White Pass parking lot, like a Nordic skier. The PM will help resolve these anomalies.

redlude97

I call it cyclocross practice. Perfect clip in on first rotation mash the gas repeat ad nauseum

Seattle Forrest

How do you like using it now that you've had it a while?

Carbonfiberboy 

Loving it. For the price, it's totally been worth while. I particularly like it on my fluid resistance rollers. As the fluid heats, resistance goes down, so now I can finally get a better fix on HR drift and thus aerobic fitness. It's also nice to be able to keep a more even effort out on the road. I now have power displayed larger than HR on my Garmin. That says it all, eh? My Garmin is out on my clip-ons, so I don't have that "looking at my stem" thing going on all the time - it's visible in my periphery.

MinnMan

So I just joined the club. Favero Assioma Duo pedals arrived yesterday. So far, I have one ride on the trainer and one outdoors. Some observations that others may or may not care about:

1. Previously I was measuring power on the trainer with the Kurt Kinetic Inride sensor. It's not truly a power meter and though it's reputation is pretty good, I wasn't sure how accurate the numbers are. It turns out, they are spot on - within a couple of percent. At least, they are when I'm careful with calibration, which means that I ride for 10 minutes to let the rollers warm up before I do the calibration.

2. I have always felt that my right leg was dominant. It just feels stronger. It's one of the reasons I really wanted dual-sided power, as I wasn't confident that single-sided power would be accurate for me. Not so. My L/R balance is about 48%-52%. That's pretty even.

3. Outdoors I had my garmin set to read out instantaneous power. I can see why usually people look at the 3 second average, but it was interesting to see how much the values jump around. I am thinking that this is partly telling me that I have some significant deadspots in my pedal stroke and that I need to be more conscious about pedaling smoothness. On the subject of which, with Cycling Dynamics, there are now actually measurements of pedaling smoothness. I need to learn what these numbers mean.

4. My power spikes sprinting up little hills are more watts than anything I ever produce on the trainer. I guess there's something to be said for the real world.

rubiksoval

They don't mean much. No one pedals in circles. You're simply unweighting one leg while pressing down on the other. I wouldn't give it another thought, personally.

Carbonfiberboy 

Here we are again. I was pedaling with my shoe uppers for much of my VT1 workout on my rollers today. Going to do it again tomorrow. Pedaled at ~130w, no HR drift over the hour. Maybe I'm not in such poor condition after all. Loving the PM.

Strong hip flexors are good. Ride duration seems to make a difference in pedaling style. Randonneurs and LD racers pedal circles. Short duration riders tend to hammer the downstroke more. Makes sense.

Good article on pedaling by a USAC coach here: https://biketestreviews.com/correct-...s-of-pedaling/

EMG image of muscle usage of a readable size here:

rubiksoval

Doesn't make sense.

I can put out the same watts in tennis shoes. I'm sure most can, save the comfort and control aspect. How would that be?

MinnMan

5. I'm surprised at how little power I've been putting out on downhills.

Carbonfiberboy 

That's because of the short length of said tests. Same with that GCN video about flats/clipless. Same with asgelle's post about 20k TT riders. If that's all one wants to do, it really doesn't make any difference. However, LD racers pedal circles at higher cadences than would be indicated by GE, and with little or no upper body movement. In short contests, of say an hour or two, results are determined by aerobic and anaerobic ability. In long contests, say 10 hours - 10 days, it becomes more about muscular fatigue. The more muscle volume one can efficiently deploy, the slower becomes fatigue onset. One can't just change pedaling styles and test to see which works better. It takes a considerable amount of training time for adaptation in the muscles, and in the neuromuscular signaling. There's only been one decent study of this which I've read, and unfortunately they've recently pulled the PDF, too bad, but here's the abstract:
https://www.ncbi.nlm.nih.gov/pubmed/21507064
which because of the very short training time, underestimates the benefits it found of pedaling circles.

My usual short endurance rides are 3-4 hours and on a 330 lb. bike. Not everyone goes to such lengths, but why not learn to pedal well and be able to do anything one wants?

If you haven't ridden with them personally, you should watch videos of solo RAAM and 508 riders. They are so smooth.

Hermes

When I started training with power in 2008, I was doing the same thing. On flat to rolling terrain, I would have solid power on the climbing portion but once I crested the hill, my power would drop like a stone even though my legs felt like I was putting in more power.

Over time, I got much better at holding constant power. Even today, I do a local climb that has sections of 8-9% grades, flattish sections and some downhill. During a threshold climb, I find it much easier (perceived effort) to hold power on the steeper grades versus the less steep or flat to downhill sections.

I think it has to do with my muscle composition and how my neurology recruits muscle fibers as speed changes. Even though, I am doing the same cadence, when I am going faster such as on the downhill sections, my neurology is topping up the energy required to keep the bike going at the faster speed to overcome predominantly wind resistance. During the climbing parts, the speeds are slower and I am mostly overcoming the force of gravity which is more constant so the recruitment patterns are different. Hence perceived effort changes as well as resulting fatigue.

For me, the more I practice higher power on flat and downhill terrain, the better I get at doing it. YMMV.

rubiksoval

To me, "pedaling well" means delivering the most amount of power to the pedals in the most economical way possible. And I do that pretty well. "Smoothness" has a different connotation as well.

You're cherry-picking an extreme outlier that is not in any way relevant to this thread or the post I was responding to (nor do I even agree with your assertion in that context, either, but I digress). In any case, kind of defies the point.

rubiksoval

Same. That, to me, was the biggest benefit of a power meter: showing the incredible amounts of time I wasn't actually putting out much power when I thought I was "training". A four hour pre-powermeter ride would probably equate to a three hour ride today in terms of kJs/ work performed. Now I typically have less than 10% Z1 time versus 30-40% when I first started checking it with the PM.