I do like to alternate between the levels on each day rather than stay at one level for a month at time or whatever time frame you may choose. I haven't quite gotten to L3 yet... have done it a couple of times, but wow it's tough! I'm working on it. I might mix in a day of just heavy lifting at a slower pace. Thanks for the discussion!
Do you have access to serious lifting equipment? Lifting the same dumbbells at a slower pace won't really improve things.
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