Avarage watt comp.

Quoted post said:

Originally posted by marlon1
Hi.

I just cycled 4.53watt/kg, for 30minutes. An Avarage watt/kg in a 30min ride is (if I'm correct) the same as your MLSteadyState.

I'm cycling 2 years.

How much watts/kg do you cycle, for how long???

MLSS is, as suggested a steady state effort where lactate doesn't rise. however, during a 30-min 'all-out' effort (i.e., a TT) there's no reason why this should be steady state even at a constant power output. in other words, lactate, VO2, etc, will drift upwards at a constant workload.

ric

No but I think tehre will no big difference. Maybe I try to measure for 1 hour...

4.53w/kg for 30minutes is very good for someone who has been riding for only 2 years. you could be a very competive racer in the hills.

i recently did an interval workout at 4.6w/kg, for 35minutes total at that power. a hard workout.

what exactly is 'very competive racer'

I don't live near hills/mountains. So going to such a place for races isn't so easy.

If I do that, I want to have some chance to win something.

5.0937 watt/kg for 30minutes is my new personal record.

(I used a tacx flow)

----

what exactly is 'very competive racer'

I don't live near hills/mountains. So going to such a place for races isn't so easy.

If I do that, I want to have some chance to win something????

Can this be broke down into how many watts per pound of body weight? how many watts per pound is good say for a 140lb rider?

2.31046 watt/pound body weight

[QUOTE]Originally posted by marlon1
[B]5.0937 watt/kg for 30minutes is my new personal record.

(I used a tacx flow)
[/quote]

i've no idea on the accuracy of the Flow, but 5 W/kg is an elite level. how fast do you ride on the road?

ric

over 42km/h for 1 hour. flat road. no wind

and no TT bike 🙁

just for reference, if it's any help.

I too have a Tacx flow. It is extremely inaccurate. Taking into account that I regularly calibrate the turbo (using the prescribed method in the manual) it is somewhat off.

When spinning at 160W (according to my PowerTap Pro), the Tacx reports 230W!

You have to calibrate it every time you are cycling

Some days I get a calibration of +1 or +2 and some days of +13!!! The voltage is also different, here it is bewtween 220 and 240Volt. The tire presurre differs every time you ride. And you have to warm it up for at least 3minutes.

I do this very time I cycle but I don't have a PowerTap Pro.

Do you know how accurate the Powertap is?? Maybe if you do the calibration and cycle direct after the calibration, the two measurements agree.

I also think it is best to cycle with a constant rpm....

Can you check this? it would be nice to know if, after this setup, the Tacx is still inaccurate.

Marlon

42kph is good for an hour on flat roads and no wind. especially since you were on a standard road bike. you could race well, assuming that you are capable of doing very high power efforts repeatedly.

'42kph is good for an hour on flat roads and no wind. especially since you were on a standard road bike. you could race well, assuming that you are capable of doing very high power efforts repeatedly.'

I can cycle 5.1watt/kg but I am only 58kg. So that's a total power of only 300watt.
I think I am better in hills. In flat races the only thing that matters is the total power you can cycle, not power/kg.

----

But I am curious how accurate the flow is?... Maybe the 300watt is 200 in real 🙁 🙁

Quoted post said:

Originally posted by marlon1



I can cycle 5.1watt/kg but I am only 58kg. So that's a total power of only 300watt.
I think I am better in hills. In flat races the only thing that matters is the total power you can cycle, not power/kg.


----


But I am curious how accurate the flow is?... Maybe the 300watt is 200 in real 🙁 🙁

Not quite right. Power/Kg is still good for the flat. Most work on flat is against air resistance. Body weight is a good approximation to frontal surface area & drag coefficient. However the relationship is logarithmic not linear so low weight helps a climber much more than a roleur. Anyway give 2 riders each with 300W the 58kg guy will be much faster on flat than the 80kg and I'd guess a 300w/58kg would be faster than a 350kg/80kg. CB was faster than Indurain at hour record.

Quoted post said:

Originally posted by Michuel
Anyway give 2 riders each with 300W the 58kg guy will be much faster on flat than the 80kg...

All else being equal (including frontal area), the 58kg rider would be able to accelerate faster and would be faster in the hills and anywhere gravity becomes a detractor. On the flats however, the two should be capable of comparable speed.

Back to the original subject...

I also use a Tacx trainer (Excel) for training, and while I have no way to verify the accuracy of the power reading, I seem to get relatively precise (consistent) readings. In other worlds, given specific gears and cadences which I use frequently and know well, the power readings from day to day seem to be consistent.

Now, several Tacx trainers use the same magnetic unit, so perhaps one way Marlon could get an idea of how his reported power levels figure into real world numbers is to find someone with the following:

(1) Tacx
(2) Same gearing (same groupset)
(3) Same crank length
(4) Powertap
(5) Same tire pressure

If this person records power levels required to turn a steady 100rpm in various gears at the "0" slope setting on the trainer, maybe that could give Marlon an idea of how his numbers compare. Naturally there will be some error, but I don't think it would be much.

i've tested various power meters to each other, and a PT to a Tacx (a few different models/units).

1) each Tacx has different power values at a true constant power, even after doing a run down calibration test

2) as the session progresses and the unit heats up, resistance (between the tyre and roller interface) decreases even though the Tacx reports the same power. In other words, at a constant velocity (true) power decreases, or at a constant (true) power velocity increases.

ric

I'm 1.80m so I also have a large frontal area. I like doing TT's but I'm not build for it. Maybe uphill TT's 🙂

--------
Now, several Tacx trainers use the same magnetic unit, so perhaps one way Marlon could get an idea of how his reported power levels figure into real world numbers is to find someone with the following:

(1) Tacx
(2) Same gearing (same groupset)
(3) Same crank length
(4) Powertap
(5) Same tire pressure

If this person records power levels required to turn a steady 100rpm in various gears at the "0" slope setting on the trainer, maybe that could give Marlon an idea of how his numbers compare. Naturally there will be some error, but I don't think it would be much.

---> No. A Tacx Flow has a calibration unit. No other Tacx has that. I assume that the calibration works ok. (for example: cycling with a higer voltage will give with the same effort the same power output) . My experience is that this is true.

!!!!!!
So measuring the inaccuracy of the Tacx Flow, somebody with a Flow has to cycle with the same speed as I do, and calibrate the Tacx before cycling.

Let's say 30km/h on slope 0. If the Flow is super accurate we will get the same power output. if we compare the power output, we can see how inaccurate te Tacx is.

Anybody here who likes to compare his Flow?? The more people/data we have, the better we can estimate how accurate the Flow is.

!!!!!

1) each Tacx has different power values at a true constant power, even after doing a run down calibration test

---> Exactly, this tell us how accurate it is.

2) as the session progresses and the unit heats up, resistance (between the tyre and roller interface) decreases even though the Tacx reports the same power. In other words, at a constant velocity (true) power decreases, or at a constant (true) power velocity increases.

--> This is why you have to do a calibration AT LEAST after 3 min cycling. To heat up the tires and more stuff.

Quoted post said:

Originally posted by marlon1
---> No. A Tacx Flow has a calibration unit. No other Tacx has that. I assume that the calibration works ok. (for example: cycling with a higer voltage will give with the same effort the same power output) . My experience is that this is true.

!!!!!!
So measuring the inaccuracy of the Tacx Flow, somebody with a Flow has to cycle with the same speed as I do, and calibrate the Tacx before cycling.

Let's say 30km/h on slope 0. If the Flow is super accurate we will get the same power output. if we compare the power output, we can see how inaccurate te Tacx is.

Anybody here who likes to compare his Flow?? The more people/data we have, the better we can estimate how accurate the Flow is.

!!!!!



1) each Tacx has different power values at a true constant power, even after doing a run down calibration test

---> Exactly, this tell us how accurate it is.

[/quote]

the results are different most times i use one...



2) as the session progresses and the unit heats up, resistance (between the tyre and roller interface) decreases even though the Tacx reports the same power. In other words, at a constant velocity (true) power decreases, or at a constant (true) power velocity increases.

--> This is why you have to do a calibration AT LEAST after 3 min cycling. To heat up the tires and more stuff.

i do. surprisingly, i do have a fair idea of what i'm doing considering i'm in the middle of writing a peer reviewed research paper on power meters!

the units (in fact most trainers) drift as they heat up. the differences can be quite large by the time you get up to 2+ hours on the trainer.

ric