StefanG

Does anyone know what the calculation is on WKO for CTL decrease on a rest day? In my current state (CTL at about 75), i'm losing 1.8 CTL on a rest day. If I were to train every other day, I'd have to hit about 150 TSS for each work-out just to keep CTL steady. So, just to be clear what I'm describing:

Sunday: CTL = 75.6
Monday: rest day, CTL drops to 73.8
Tuesday: after training of TSS = 150, CTL increases to 75.6
Wednesday: rest day, CTL drops to = 73.8
Thursday: after training of TSS = 150, CTL increases to 75.6
Friday: rest day, CTL drops to 73.8
Saturday: after training of TSS = 150, CTL increase to 75.6

So, starting with the baseline CTL value of 76.6, after 3 rest days and 3 training days (alternating) CTL remains at 75.6. I can't imagine my fitness wouldn't increase if I trained every other day, hitting 150 TSS on those days.

What am I missing / not understanding?

jrobe

CTL is a moving average of your total training load over 1-3 months (you can change the time frame as I recall). That seems about right that if you work out fairly hard but only every other day, that your chronic training load would stay about the same. If one is trying to build their fitness (for an upcoming race as an example), the goal might be an increase in CTL of 3-5 per week. In your case, this would require more work load than 3 rest days a week. As I recall, and increase of CTL greater than 7 or so would be considered too much and would possibly be counter-productive.

This isn't measuring your total level of fitness, just you training load and whether it might be too much or too little for fitness gains. Sometimes, the goal would be to just maintain the same weekly load.

StefanG

That was just an example to illustrate that the CTL decrease seems awful high. I personally train 4 to 5 days per week with typical CTL increases of about 4 to 6 week over week (excluding recovery weeks). I'm just surprised that as my CTL continues to increase each week, that the rest day CTL decrease has gotten extreme. It makes sense that as you become more and more "fit" it would require a higher load/stress to maintain that vs when you had a relatively low CTL, I'm just surprised its dropping as much as it is on a rest day, so was curious about the calculation WKO uses. Its my understanding that CTL represents "fitness". I have a hard time believing that if I followed the training example above that my fitness would not increase each week vs staying level as WKO would indicate.

In my training plan, the real jump in CTL comes from my 3 - 4 hour ride on Saturday or Sunday each week. And then after that ride and before next week's big ride, I'm basically just maintaining my CTL (according to WKO), although in reality I'm busting my butt on the trainer for 2 hours (3 days a week) doing FTP, VO2Max intervals (hitting about 150 TSS), I got to be increasing my fitness during the week.

achoo

WKO is a tool - don't get suckered into thinking the numbers you get out of it are more than a general indicator. I fell into that trap last fall and made my WKO numbers go through the roof - my CTL was over 130 by mid-November. Yet I'm much faster now, and that's the number that really matters.

If you want to make the numbers WKO puts out go up, just toss a few 30-sec sprints into each ride. Try it - do a ride exactly like an earlier one, where you'd expect about the same TSS. Then, add four or five 30-sec sprints at the end. They don't even have to be really hard, just make sure your peak power on each one is a good amount over your FTP. Your TSS for the ride will probably wind up 30-50 points higher.

For me, WKO also seems to overestimate the TSS for longer rides - those greater than about 3 or 4 hours or so.

And more applicable to what you're doing, it seems to me to underestimate the TSS for 1-2 hours rides where I put out a steady power.

I've recently started using Golden Cheetah in addition to WKO for those reasons. I'm still getting a feel for Golden Cheetah's numbers, but right now I'd say that, for me anyway, WKO's TSS numbers track more closely with my short-term muscular strength, while Golden Cheetah's TRIMP numbers track more closely with my cardio endurance. With Golden Cheetah's BikeScore and DanielsPoints sitting closer to WKO's numbers.

Drew Eckhardt 

CTL is an exponentially weighted average over the preceding 42 days (or what you adjust it to reflecting your physiology). Riding every other day with TSS = 150 I'd expect you to be a hair over 75 on riding days and a hair under on rest days because the most recent 150 or 0 is weighted more heavily than older values.

You're getting some increase since TSS = hours * (NP/FTP)^2 * 100, your FTP is increasing, and total joules spent going up since you're increasing your power zones to match the FTP increase thus resulting in a correspondingly higher NP.

Beyond that you shouldn't expect your capacity to work increase significantly since you're not stressing your body more than it's used to (that's what CTL represents).

You need a ramp on duration or intensity to accomplish that which will be reflected in daily TSS, ATL, and CTL where there are limits on sustainable TSB (CTL - ATL).