What would be the minimum requirement in terms of volume & frequency needed to develop the aerobic system i.e. the physiological changes that come from training at L2?

I understand that certain changes and adaptations occur from training at this level but at what point does it become ineffective in terms of volume & frequency? i.e. I’m sure that 20hrs per week @ L2 4-5hrs a day would bring about massive changes but would there be any point in training say 6hrs per week at L2 @ 1hr a day or would just one 6hr L2 session be better?

I’ve also read that there are certain changes that only start to occur after the first hour or so spent at L2, so I’m assuming it would be better in terms of physiological changes to complete 2hrs continuously rather than break it up into two 1hr sessions.
I hope this is making some sense and I understand that is dependent upon a great many factors but I am just curious to know.

Thanks for reading

I wouldnt bother with many 1h L2 sessions. If you can plug in a 5h+ L2 session, then go for it, especially if you race marathon. Other then that I'd stay at L4, SST, and L6

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I don't think there is much to be gained by doing a bunch of 1-hour long L2 rides.
If you only have one hour to ride, it should probably either be a recovery ride, or something with some degree of intensity.

As for 6 sessions of 1 hr in L2 versus 1 session of 6 hrs at L2, I'd vote for the latter, but my choice would also depend on what you would be doing the other 6 days of the week for that option.

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