Race Rehearsal Power File Questions
Prepping for IM TX. RR #1 was today. It was very windy (i.e. 25-35 MPH), about 90 degrees, and the route I used was hilly and into the wind the first half, with the wind the second half. It was also pretty hilly with about 6000 feet of gain. Bottom-line, it was a tough ride. It was my slowest century in several years at 5:42.
The power file data seems odd to me and I hope someone with more data file experience to give some advice. My FTP = 235.
Ride stats: 6:01, 108 miles (18 MPH), Avg Power = 153, NP = 178, IF = .75, TSS = 344 (not a misprint).
Going into the wind I saw the average watts on the Joule creeping up so I backed off. When I turned from into the wind to a tailwind, my average power was spot on, about 167. I rode home fine and the six miles running afterwards were all at the right pace. That said, I could tell it was a tough ride.
Question 1: why is the TSS so high?
Question 2: I was watching average power to meter my effort. Was this the right metric to watch?
Question 3: in hindsight, should I have backed off more? My target was .71 IF and TSS of 277.
Any other advice is certainly welcome.
Comments
Hi Tim
I am sure some WSMers will chime in here but here's my two cents worth.
You should aim at instantaneous watts (well its probably a rolling average of 30 secs or similar).
You are trying to get your NP is close to your target watts as possible.
You should be aiming for a NP/AP of around 1.03 depending on how hilly the bike course is.
Your very high TSS is a result of your NP being a fair way higher than your target watts.
But don't worry. This is the reason EN has us doing two RRs.
Cheers
Peter
Tim,
Your TSS is high because your VI is high. I believe that is what Peter is referring to (1.03). A score of 1.00 will indicate your AP and NP match. You want to get as close to 1.0 as possible with 1.0 being 100% of your target watts.
It's very important to watch real-time watts when you ride and not average. Real time watts give you the instant feedback necessary, especially on a hilly course. You can see when you'respiking your watts as you do it. Watching average watts doesn't give you the level of immediate feedback you need. You can cook yourself and won't know it until it's too late. It's not a bad idea to check your average watts periodically. I actually usually don't.
Before I answer number 3, how was your run? Did you run well off .75? If not you definitely want to back off. I also think if you ride steadier you will have a better shot at hitting your target more accurately. Probably better to be conservative and save it for the run. Riding a steady .71 should set you up nicely and give you a lower TSS score.
Like Peter said, you've got another RR to work it out!
I also ran fine afterwards. Tired obviously but was churning out 8:00 - 8:30 miles.
It definitely takes practice to learn how to ride steady! That's what the weekend rides are for.
FWIW, I checked the math and the TSS looks right, given your IF and time in the saddle:
.75 squared times 100 = 56.25 TSS per hour
multiplied by 6 hours = 337.5
add just a bit to the time and/or IF and 344 is probably right on. I'm really surprised you were able to run as well as you did. But not sure if that would be sustainable past (or even up to) Mile 18.
Agree with everything already said. I also monitor actual watts (not average) and, while it jumps around a bit, you can get pretty good at estimating the median (target).
Looking forward to meeting you in The Woodlands!
Paul
Tim - when I say we look at real time watts, I use a 5 sec (I think its 5) rolling average. As you say, using a rolling average does smooth it out to make it easier to use as feedback on how hard to push on the pedals.
As Matt mentioned, the weekend rides is when you should practice sitting on a target watts.
As others have mentioned, once you get the skill of riding steady, you can turn it on and off when ever you like.
Cheers
Peter