A 29 second PB over a mile long hill… keep doing what you’ve been doing…! 
Great result,welcome to the 5w/kg club. A pretty massive effort… you’ll probably find 5w/kg happens pretty easily now
Nothing easy about it! But I am interested to see the difference between road and TT bike… I got 330 watts a few years back but was probably slightly heavier.
Is the basic rule 20 minutes at 5wkg, or is it a FTP test that results in 5wkg FTP?
The first is maybe possible for me in a few months if I keep riding like this. The second may be a few months longer.
I’ve always used the 20 minute test as my barometer. I’ve never done an all-out hour but the way to estimate it is multiply your 20 minute number by 0.95. So for me 320 x 0.95 = 304w. 304/62.7 = 4.84w/kg for an hour. I would find 320 for 20 easier than 304 for 60…
Okay, then maybe I will come back to this thread in about 5 months…
The basic premise at the top of thread was 5w/kg for 20 mins.
326 watts, 175bpm, 20mins, 92rpm, 62.7kg, 5.2w/kg.
Was on the TT bike this time but in an upright position. Had my road shoes on as opposed to my tri shoes and had them done up very tight. My weight has stabilised and it seems you do get a wee bit more power out of the upright TT bike position than the road bike position (320 watts on the road bike 2 weeks ago). Will try another FTP test on the TT bike in the aero position in a couple of weeks but suspect it’ll be around 300 watts.
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That’s a great result, it would be interesting to see what you can do in the aero position now. There is no way that my FTP in aero is close to me road bike position FTP: due to the amount of Zwift races, I set my FTP standing for 20 mins, pushing big power at low cadence. Its great for long climbs, but not that useful for TT bike riding. I am now working to transfer some of that strength to riding when seated
Aero position trial will be done in a couple of weeks. It’ll be a good 10% down I reckon. There are so many ways to improve aero. I’m a bit gutted I didn’t shave my legs when I went to Kona because Specialized say it gives you over a minute per 40km. You’d also gain in the swim. You can get aero socks and aero arm coolers too, and my 2-piece top and shorts weren’t great either. A good tight one piece would help. And then there’s the vaporfly question…!
Just did an outdoor 40k TT effort, in 56:55, on my TT bike. took 30s off my previous 40k TT time, on this loop, which I set 5 weeks ago (and 2m30s faster than ever ridden prior to that). I felt like I was giving 100% effort, however, my avg power was only 303w, well down on my FTP. These are my observations
I can hold around 320w in TT position outdoors. On my road bike doing a hill climbing TT I can hold 345w, on my Turbo trainer, I can hold 375w
Descents, traffic, corners, round abouts etc all have a big impact on power. On the turbo, I ride standing, at low cadence (sub 70rpm) on this ourdoor effort, I was riding at 90rpm only standing on one climb. I think that because a Turbo Trainer is fixed, you can adapt your technique to drive power very effiicently through the pedals, in the real world, movement of the bike makes it harder to drive efficiently.
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Same power meter?
My Kickr is 4% higher than my Garmin Vectors.
Wonder if anyone has ever tried to quantify the losses from a bike moving under you on the road?
Yes same Assioma pedal power meter, used indoors and outdoors.
Even though my perception was that I was riding max effort on TT bike, my avg HR was 158bpm, while indoors and on hill climbs, my HR is usually around 170bpm. Maybe an indication that I am carrying some fatigue
Here is the power from my TT bike ride
Here is the power from a Zwift race last week
On my TT bike, I started hard, then the power dropped a little, which does indicate fatigue. When I got into more built up areas, you can see how much variability there is. Overall, VI is 9% which is high
A VI of 1.09 is huge. This is the issue with outdoor riding: you can get the power down with a nice breeze and really get some hard intervals or climbs in, but you cannot get a steady state long ride with traffic, stops, bad road surfaces, and down hill sections constantly causing your power to rise and fall.
I bet if you could find a closed circuit you could get close to your Zwift numbers.
I see a lot of top zwifters doing this. Power transfer on a static turbo must be part of it, and there is certainly a difference in feeding your full body weight into the pedal stroke (hence why the trainerroad guys says you are not allowed to stand at any point during a ramp test as it invalidates the results).
But moreover, you’re getting absolutely zero aero cost of standing for all that time indoors. Intuitively outdoors, unless climbing, or powering over a lump, you’re going to naturally sit to get as small in the wind as possible. Indoors, power is the only piece to the puzzle … outdoors is a whole host of combination of factors to create the maximum speed.
I know that the above is probably an obvious statement. But my point is you probably could get close to your zwift power if you chose to ride that way outdoors. However you’d almost certainly be slower as you’d be a brick.
Personally, I’m still ultimately using zwift as a long term plan towards IRL racing improvements, so I very rarely stand unless it is a small lump in the game which might well be a point I’d stand outside. Or to break position for a few seconds on a prolonged climb, again as I would do outdoors.
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All valid points @stenard - this is why I don’t get too hung up on the Zwift numbers. You’ve only got to move your legs in a piston like up and down motion get decent power - the biggest issue for me inside is overheating, nothing else is a factor.
So I would call Matts hour of power at 303 watts his road or aero position ftp and leave the Zwift standing up pushing a big gear numbers for Zwift
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More likely I think, (from the brief stuff I’d read) that you simply cannot use the aerobic resources at your disposal in the conditions (whatever they might, I’ve not read back enough, but it seems outdoor TT vs indoor out of saddle etc.) Plenty of supply available, but you simply can’t use any more.
That is of course good, as aerobic limits are harder to improve, so you should adapt relatively quickly, and even if you don’t as a triathlete, the aerobic demands being lower means your ride is still at a lower overall intensity giving you more for the run.
I certainly think it helps to break up your zwift racing with plenty of intervals out of the saddle. But it’s hard to stay out of the saddle for long periods.
3 x 20min FTP tests over the last few weeks. One on the road bike, on the hoods and tops. One on the TT bike in the upright position.
One on the TT bike in the aero position.
All at roughly the same level of fitness.
Road: 320W, 177bpm
TT upright: 326W, 175bpm
TT aero: 308W, 168bpm
I was slightly less tapered for the aero TT test. I couldn’t quite hit the highest heart rates in the aero TT position. That said, it was still slightly higher than I thought. I think it’s easier to maintain higher watts on the TT bike when actually on the road compared with on the turbo. It’s probably also easier to maintain the aero position on the road, for whatever reason. I found it tough to hold the position at high intensity for 20mins on the turbo, I’ve never tried to do that before.
So for me it is interesting to know that my aero TT FTP is around 6% lower than my maximal upright FTP.
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