Intervals icu fitness levels

Hi … help needed from someone that uses intervals.icu

I have been using intervals.icu as a way of checking my fitness/data over the last few months etc. I am doing the TT plan (3:1)at the moment and have noticed that my fitness levels have dropped since doing the MAP plan previously and appear to be at best stabilising and even dropping, doing the plan exactly as shown. According to the instructions 1) To get fitter the fatigue line (purple)needs to be higher than the blue line… 2) When in the green (optimal zone) you are gaining fitness. Well the last time was in the optimal (green) zone, and only just and for that day was on the 14th October after doing the “blender”. Since then I have barely managed to keep the purple above the blue, even adding extra workouts to the plan to try to give me a bit more stress, so in reality I have not gained any fitness from that date until now ? Also, the TT plan has two rest days in it which I use to add workouts from the strength but on those days my fitness line drops along with the fatigue line which then takes me days to catch up again and that again is the case today. Today’s planned workout is “outskirts 1 Route 66” but I am going to add A/C 2 sets of 6 x 20/40s to bump up the stress a bit + maybe I should add a workout to the “rest” days, surely though I shouldn’t have to? The workouts are not any easier than they used to be and if I was getting mega fit then the intervals.icu data would have me in the fit/optimal and fresh zones all the time. Cheers

Just checking - have you set your power zones and HR zones up correctly on the site?

1 Like

Have you asked this question on the intervals.icu forum? Mayby these short workouts aren’t appreciated enough? I looked up my fitness on intervals.icu and in the months I mainly do indoor workouts I also barely scratch the blue line with my fatigue.

Can you show a screenshot of the fitness page?

Maybe add a LSD ride?

How is your heart rate during the workouts?

Yes, but I have just had a look through the other settings and the “form” was set to absolute value but the recommendation was to set it as “percentage of fitness”. I have done this and now the green has appeared more and earlier rides which were heavily into the green are now red (overtraining). I have also shortened the warm up period (which apparently is discounted from the data) from 20 minutes to 15 as many of the intervals I do have shorter warm ups or some more strenuous stuff earlier on in the warm up. Will see how that affects things now… cheers

I have just changed a few settings as mentioned in my comments to oggie41 but here are two screenshots before with the form set at “absolute value” and after with it set at "percentage of fitness. Today’s workouts are shown on there.

intervals icu percentage of fitness value

Yes, I’ve got mine set to “Percentage of fitness”.

I’ve got my Warmup and Cooldown set as 10 mins. I think that’s only used for the decoupling calculations though.

1 Like

Hi @ozmadman

I use intervals.icu and the only way to make a significant increase to your fitness score is longer duration rides. I have added a screenshot of my chart for the last 6 months and the 2 big spikes are due to a 3 day, 310mile sportive in June (3x 6hr days all around 86% intensity) and then a 6 day holiday at the end of September (6 consecutive days between 3 and 5 hours, 75 - 80% intensity).

Between these spikes, I barely kept my fatigue above my fitness, and it was simply down to a reduction in volume.

Since the start of October, my fitness score has dropped from 82 to 64, as I have started to focus on indoor sessions again. The only ride that lifted my score in this time was a high intensity outdoor ride of over 3hrs.

I have just completed a couple of weeks of MAP focused workouts including downward spiral, revolver and 14VC. I am in no doubt these workouts are continuing to improve my power on the bike, but at best, and despite their intensity, these shorter sessions are barely maintaining my intervals. icu fitness score (which I would expect to continue to drop down to the low to mid 50s through the winter).

It would be worth searching the forum for articles / posts on chronic training load (CTL) and listening to the knowledge podcast for a more detailed explanation.

Thanks for that, at least I am not the only one! It does look like then that unless you go out and do some long rides, or long indoor rides your fitness according to this set up may not appear to be improving and the only way to keep improving it seems is more and more long rides? This is a bit discouraging especially when most of the Wahoo training is based on shortish interval workouts which I do. I have worked really hard and dragged myself up to a fitness level of around 45 (whatever that actually means?) in the time (5 months or so) I have been doing training with the Wahoo systm and at the age of 69 my FTP was 3.49w/kg from the last 4DP test I did so I am pretty pleased with that. I will stick with the training plans and Wahoo workouts, these stats are interesting but to be taken with a pinch of salt sometimes. Thanks for the podcast reminder, I have listened to that before but will give it another listen cheers!

I’m not too familiar with intervals.icu in particular, but remember that the ‘fitness’ metric in things like Stravas and TrainingPeaks really just means ‘volume’ (and I think i.icu uses the same?). It is simply just your average training load from the last 6 weeks. Training load being defined by TSS which is FTP bbased only and has no appreciation for HIIT and the like.

I did 9 Hammers and Attacker this week. If I did those alone my average load for the week would be the equivalent to 50 mins a day of zone 1. Would the two give me the same fitness bump? Nah. (Also, is it always appropriate to do the former? Also, nah).

I like to look at CTL (‘fitness’) because it gives me an indication of if I’ve been managing to train much. Also I put my training plans in to TrainingPeaks so I can see my forecast CTL over the next 12 weeks or so, which is motivating, gives me an idea of easy/hard weeks, etc. But I don’t consider it to be much of a measure of how fit I am. I get a much better gauge from how I feel during/after a session (that is, lets remember, done at exactly the same wattage as the previous time, all things being equal), average speed/segment times on outdoor rides and ultimately of course test results. ‘Fitness’ like this also doesn’t really account for rest, which is ultimately when we recover, reduce fatigue and get stronger. Go figure.

3 Likes