Add a third training day for lagging muscles
Israetel argues that simply adding sets to an existing workout can feel like 'junk volume' and be mentally draining. By spreading the same per-session volume across more days, you accumulate more total work without the dread of a marathon session. He emphasizes that this is a 'big deal' and can cause notable gains if low volumes weren't working. He suggests doing this only for a few muscles that recover fast, to keep systemic fatigue in check.
More frequent stimulation provides additional muscle protein synthesis spikes and keeps the muscle in a net anabolic state for a greater proportion of the week, while the per-session volume remains manageable for recovery.
Instead of doing curls twice a week, do curls three times a week. Now you've gone from doing 10 sets of curls total per week to 15 sets of curls total per week by just adding a session for biceps. Big deal.

