It doesn't matter what intensity you do them at (for your intended purpose) but they need to be longer. 1:45-2:00 hrs.
I can't think of a reason to do them above z2.
@miro_o started
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It doesn't matter what intensity you do them at (for your intended purpose) but they need to be longer. 1:45-2:00 hrs.
I can't think of a reason to do them above z2.