How do you know you reached your limit?

[mrlobber]

Take a look at "xert".
. It's in beta right now. Does a calc that gives you "MPA". Sort of like how much gas is left in the tank at any point in a ride.

Xert is cool, however, the thing with MPA, which hasn't convinced me yet about the approach, is that it doesn't seem to take into account any accumulated fatigue from a long ride, which everyone, I think, agrees, that after 6 hours on the bike (even if only endurance pace), you won't be able to churn out the same power above your threshold for the same duration as you would be after only riding 1 hour.

[goodboyr]

Lol. That came right out of the wattage discussions. Not sure if that is true, or a strawman but it's not going to stop me from giving it a try.

[mrlobber]

I might have sounded like I copied/pasted this from somewhere, but
1) I'm a Xert user myself
2) I'm speaking from my own experience here. Of course, MPA as such is just a concept and at times might have little connection to real performance, and when I'm reviewing my training/racing in Xert, for training the MPA concept does work extremely well, within a couple of watts. For racing, however, I've been totally dead in some races in 2015 where I've clearly spent up to 30 mins in my VO2 max range in the race (summing all the bursts together), but from MPA perspective Xert keeps saying I was almost as fresh as at the start of the race

[bucketrider]

How do you know you could (not) reach a higher value, e.g., 5W/kg?

My age, training, weight, background, etc. seems similar. I have power data for the last dozen years plus VO2 tests from the 80-90's when I raced a lot. No recent racing but l still train the same (I enjoy it) with 15+ hrs per week including hard and easy bits.

With all that said, I've got a nice data set to study (n=1) the decline of my physical abilities.

Observations:
age 20-35 likely my best w/kg-wise, FTP 4.9
age 40-45 w/kg plateau/slow decline, Beg. FTP 4.7 - End FTP 4.6
age 45-53 steady consistent w/kg decline across the board
....FTP down 8%, FTP 4.2
....5min down 15%
....1min down 20%
....5sec down 20%

For me,"improving" means just trying to slow down the decline. My best days performance-wise are well behind me. I hope yours are not...

Good Luck