Is Endurance training essentially defined as riding below LT1?
How does TrainerRoad determine the target intensity for Endurance rides?
(From what I understand, it is mainly based on a fixed % of FTP and not individual LT1 or heart-rate response.)
I usually ride Endurance/LT1 at higher watts than TrainerRoad prescribes, because I have done a lot of aerobic training and can sustain higher power without heart-rate drift.
I have a naturally high heart rate: max ~200 bpm and LT1 around ~160 bpm.
(High heart-rate responder profile.)
Do Endurance rides still provide the intended adaptations if they are done at noticeably lower watts than my true LT1, or would it be better to increase power as long as heart rate remains stable and clearly below LT1?
Endurance adaptations happen across a very wide spectrum of zones but I would assume most people refer to endurance rides as z2 in the coggan zones and below lt1 if you are using a 3 zone model.
As long as you are fresh for your hard rides you are probably fine riding at a higher intensity for z2.
AFAIK, the biggest difference between riding your endurance above vs below LT1 is the increased fatigue for going higher, followed by a slightly stronger training stimulus, assuming duration remains constant. Though it should be easier to go longer if going easier, so real world sometimes duration changes, which can make going easier better, as volume of endurance matters most.
There isnât one standard definition for endurance, at least not with specificity. Itâs universally going âeasierâ but thatâs vague. Consider also that an untrained athlete could have a very low LT1 compared to LT2, whereas a highly trained can be much closer together. This means that a tempo ride could be below LT1 for some well trained athletes, for example.
Trainer Road simply uses % of FTP to assign zones. This is an imperfect system, because it doesnât even try to map out where LT1 is, it just assigns these zones as those easier than tempo. That said, its basically the same system used everywhere, since its difficult to accurately measure or model LT1.
Complicating matters, is that the new AI model will vary in how intense it assigns your endurance rides. For me, my long rides have gone on the low end of endurance, and shorter endurance rides have been on the higher end. That seems reasonable enough, but N=1, and also it hasnât been out very long.
I seem to recall LT1/VT1 mapping together nicely, but I canât find a (reputable) source for it at the moment. Its pretty easy to feel when your breathing starts to get elevated during endurance riding.
I have repeatedly tested rides of over two hours to find a point where power and heart rate remain stable, together with nasal breathing and an RPE of around 3.
I think it also depends on your goals. LT1 is mostly upper bound Z2/low Z3 for some. For shorter endurance rides maybe yu could ride just below LT1 but rides from 2h to 5h you are better just let the watts drop for the same adaptations because it adds way too much fatigue for its purpose imo.
Consistency is the main driver for aerobic adaptations. Better go 2 days at 6O/65% for a couple of hours then one day at LT1 for a couple of hours.
Maybe if you do low volume or you want to improve power at LT1 you can ride more around those power numbers.
Most research and coaching that I have seen is that the window for the aerobic or endurance benefits from âeasyâ rides or runs is very wide, that if you ride at say 55-77% of your FTP you will check the boxes. Stroke volume, mitochondria, fuel burning shift, etc. Pushing to the high end or above that range (well into tempo⌠âEn+â, will check the same boxes but result in more fatigue/stress and i believe be more gains/adaptions for same duration. If short on time, it could be shortcut to the TSS and training signal, seems that is a move TR is moving to lately with every Zn2 ride being at the high end. Myself coming from marathon/ultra training, it was always a if you can run at a 8:10/mi pace and get nearly 100% of the gains as running at 7:50/mi⌠why not just run 8:10 and feel a bit fresher for next workout and also maybe less injury risk. Family/friends are always surpised how slow most of my running is, lol, then I always as them why they train all their runs faster then most of mine! lol (yet I can run a marathon at a pace they canât run a mile! lol). Donât go chasing fatigue, do less if it still gets you the gains.
I see it as a balance, if I have a 3hr easy ride (big mountain) on Sunday and next big workout Tuesday⌠I can keep IF at planned .68 where most of the ride is blocks of 70 to 75% of ftp w/recovery of 65%âŚ. or I could break up the 65 and 70% blocks with a minute or two here and there at 72-75% as well if HR is steady/low and feeling easy.. essentially modulate power target to maintain HR in my aerobic range. BUTâŚ. knowing that it could lead to more dead legs on Tuesday. After a few weeks you can kind of find that range where it feels like âworking easyâ but Tuesday workouts still feel good enough!
