2-a-days 
2 Likes
How do you measure kJ on your runs — Stryd? I’ve seen ~70kcal/km as a rough guide
Yes, Stryd. However, I run mostly up and down a mountain:
Often on fairly rugged trails. Furthermore, Stryd is pretty poor when it gets steeper.
Either lower power or just repeat it. Once decoupling gets low (doesn’t have to be zero, say less than 5%), extend duration first. Then once you get out as long as you want to or can go, you can go harder. But really if you start riding by RPE a lot of this can start taking care of itself. You’ll know when you’re cooked without needing a HRM to tell you!
1 Like
Doubles FTW.
Had a athlete of mine who went to Brown for a summer internship. She couldn’t run 60 min straight due to being under 18 and specific places and times they could workout. So she instead did 3 miles in the morning and 3 miles in the evening. She came back super fit.
In my peak days training for the marathon standard, I look back and I overdid it with the doubles. If I had a 13-15 mile day there was no need for that additional 5 mile run in the morning. Or the next morning.
Now that I’m older…and on the bike I am back to loving doubles. But more due to time. 2-3 hours on the bike just isn’t possible on the weekdays with work and two young kids. But an hour in the morning and an hour ride after work is.
Lately been experimenting with doing a morning VO2/threshold/SS in the morning, then coming back for 30-45 min anaerobic/sprint in the afternoon. Then taking a couple days between of just riding. We did something similar in college where we did a tempo run in the morning then come back for some 300’s in the afternoon. The key now is I don’t do anything the morning after this and get a full 24 hours before a chill ride the next day.
Thank you. This is a learning experience for me and I appreciate your input
Yesterday’s workout saw my HR sit higher for a lower power, presumably due to fatigue carried over from Sunday. As you say, RPE could have been used - everything was fairly easy…until it wasn’t. About 1h40 in RPE went from 3 to 6, just as my HR went up by 10. So I lowered the power to get my HR back down and did the last 20 minutes
Interesting (for me at least!)
I started ‘base’ 5 weeks ago and have been riding a mixture of 90-100mins@65-70%, and 45-90mins@~LT1, with a weekly 3 hour Sunday session @ 65% with progressively longer LT1 intervals.
Bike intensity has been low, a 4x8 or 30/15 session 1x/wk, max out around 11 hours. I’ve also been weight lifting 2-3x/wk.
Week gone my Sunday ride was 2hrs @ LT1 power, ~1% decoupling over those 2 hrs. I could extend this to 180mins in theory, which is usually the max uninterrupted ride time I can get on a weekly basis.
I’m a road racer/crit rider so my usual events are 2.5hrs and less. Should I extend LT1 intervals out or push intensity up slightly while keeping HR on target?
I’ve noticed my pwr/HR for LT1 and 65-70% rides has improved around 3% since starting this protocol!
2 Likes
Nice work. My goal is to start an approach like this from December on. But the intensity in the beginning not every week a session because I try to aim at 15hours a week. So maybe a 30/15 or 4x8 every 10 days.
Managing fatigue, I would try to go as long @LT1 as possible. Maybe check EF improvement? And then push op the power or re-test LT1 power?
1 Like
I think 3hrs @ LT1 would be pretty solid, its around 78% of my FTP (maybe more as FTP is probably lower than during the season). I have another 5 week block planned and I think I’ll repeat what I’ve already done but add in more overall LT1 sessions.
I had lactate/VO2 test done in Jan and 140bpm was my LT1 inflection point, I thought this stays pretty static and EF just improves? I can see in my pwr/HR graphs that this is the first inflection point also.
Good indication that you need to go easier earlier. Typically people who are decently well trained won’t decouple much until 3+ hours, so bang away at longer endurance rides and keep the power down early. In my early base this season, extending duration and total weekly volume, it wasn’t uncommon for me to start my rides close to 55% of FTP and end them at 65%, overall IF of .59 or .6 on a 5 hr ride not unusual if that duration is challenging.
It might be worthwhile to take power, TSS, KJ, IF, etc off your head unit every once in a while and just use cadence, RPE and ride entirely by feel. I sometimes fine myself “chasing” NP/IF later on long rides, so I’ll take it off and go by feel.
2 Likes
How do you find this pairs with VT1?
I think I needed to hear this! I got the idea stuck in my head this year that if I’m not hitting 70% FTP for an average power on my endurance rides, I must be doing something wrong. I spent way too much time chasing that number early in a ride and tiring out sooner than I’d hoped to.
I appreciate your contributions here (and elsewhere) Kurt!
3 Likes
I’ll be honest I haven’t done any proper testing around this. I really should… combination of not having a sound protocol to follow, and just feeling like power @ 140bpm feels ‘happy hard’ - it’s certainly not an all day pace; I’m not nose breathing, but not breathing hard either. I would say it feels right (e.g. flirting with tempo but not quite).
What’s a good protocol to follow to find VT1? (Is this a can of worms question?) 
Interesting that you need to go that low as to not be going too hard later. I just started trying to figure out my zone 2 this week, and did a simple 15m warmup, then ride at 225w and see what happens over 30min. My heart rate basically stayed between 136-142 the whole time and had very little drift, but this def doesn’t seem nearly long enough now that I’m looking at what you are doing.
I only typically ride for one hour on the trainer, so I’m wondering if only doing an hour or so of z2, then maybe I’m doing it correct? Meaning, the longer and less zone 2 fit you are, the lower wattage you would need to start. And the shorter the z2 ride, I can get away with riding a little higher watts as it won’t have time to drift too far.
For finding VT1, just ride at RPE 3/4 and take note of when your breathing changes. It’s not a massive change, but for most people you’ll go from a very subdued breathing rate, to something where you notice now you can’t talk quite as easily as before, you certainly can’t nose breathe, and your breathing rate is increased.
Personally, I find that VT1 is a great proxy for ~LT1. When I’m out doing endurance rides, I try to stay below VT1 unless I’m purposefully wanting to push at or above LT1 for some reason. I’ve never tested my LT1 other than doing some of the HRV equivalent tests (that aren’t of much value), so it serves as my way of measuring that I’m riding below LT1 which is where I want the broad majority of my endurance riding to be.
I don’t have to go that easy. I can (now) certainly bang out 5+ hours at 65%, but I find that building into endurance rides leaves me less fatigued, and usually my average power ends up higher because I might be finishing right around 70% and feeling strong instead of just hanging on at 65% and being pretty tired.
And that’s what I was doing when I was building volume. My longer weeks in 2021 and earlier were 10 hours. More normal was 6-8. In 2022, I’ve been averaging almost 12hrs per week, and that includes quite a few 0 hour weeks for vacation, injury, COVID. Having gone through my progression pushing my duration out I’d say my normal week is on the order of 14 hours right now.
So where a 4 hour ride was long for me in 2021 and earlier, I’m pretty regularly doing 4 hour rides and some 5 hour rides now. But early in my base season, those 5 hour rides were taxing so I would make sure the meter the effort early on. I don’t need to do that as much now since my endurance is a lot better than it was.
Cardiac drift is a useful metric when looking at progressing your endurance. I am not tied to it, but I do look at my athlete’s long rides and see what their drift is. When I see a 4 hour ride with 18% Pw:HR, I know I need that athlete going out and doing a lot more 4hr rides before I progress their duration or add any kind of higher power. Over the course of several months, I see it come down, and then I add duration if I can, power if I must.
If I see an athlete with 10% decoupling on a 2hr zone 2 ride, I think that they’re either really lacking endurance, or they’re really fatigued.
If I were doing an hour of zone 2, I’d be right up at LT1, my proxies being either VT1 or like 72-75% of FTP or so, but ultimately it’s not that important if you’re just adding volume. These days when I’m adding volume after a VO2max set or whatever, it’s usually at like 0.64 IF regardless of if I’m adding 1 hour or 3 hours. I’m just riding by RPE.
3 Likes
I stumbled across this guy https://twitter.com/lmagallego?s=20&t=g-7QE31-3KT9oa1Wocx8Wg who is doing some work using the AlphaHRV Garmin IQ App to try and find where VT1/LT1 is using a sub maximal ramp.step test. I’ve been trying it and it seems to give a very clear indication where VT1 is. My conjecture is that (for me at least) ISM Z2 is the inflection point and plus 25W. The idea being that the inflection point is the Aerobic Threshold. You basically plot the Respiration Rate divided by Alpha1 against Time, It make seeing where the inflection point is fairly clearly. Still a work in progress re Ramp Rates & Step values and whether it does line up with a lactate test.
From a practical coaching and training perspective, finding VT1 is pretty simple if you know what it is. You don’t need to test all this stuff and try to align it with whatever. You just look for when breathing changes and you can ID VT1 within 10W or so. And then you can use that as a practical datapoint about where you can ride above, below, etc.
I really don’t get what we are trying to accomplish by nailing these points within a gnat’s butt correlated with power and heart rate and lactate levels, especially considering all of it probably changes somewhat day-to-day, and riding 5W +/- might matter to Tadej Pogacar riding 25hrs per week, but to most people riding 6-10 hours a week… just go ride your bike for a long time at a moderate pace.
10 Likes
Thanks I’ve fixed the link I think. Yes I’m aware of the potential issues with Alpha1 but its something I keep playing with, Combining it with the Respiration rate seems to be something new and there may or may not be something in it. If there is it is certainly a very simple thing to do.
1 Like
I just find it interesting how the different systems in the body react in approximate synchrony at different intensities. Personally I know when I’m well over the threshold and I know when I’m well below it. I have difficulty in telling when I’m going through it.
1 Like
I am always interested in the different modeling of all this stuff. If someone can figure it out bang-on then it can save time in determining these things for whatever they’re worth… but what they’re worth is probably less than we think, and I would bet most people reading this thread this deep probably have a decent feel for their mean VT1 power and HR, and would take about 15 minutes of riding to find it in any given day.
3 Likes