I train every other day. Not Monday, Wednesday, Friday. Every other day, which lands as four sessions one week and three the next, on whatever weekdays it happens to fall. It has worked better than any weekday schedule I have run, and the research says that is unsurprising.
What the frequency research actually found
The popular version is that you must hit each muscle at least twice a week. The literature is more careful than that.
Schoenfeld and colleagues ran a meta-analysis specifically on volume-equated frequency comparisons, and found no significant difference between higher and lower frequencies once total volume was held constant. That result held across their categories, including in trained lifters and when looking at direct measures of muscle growth.
An earlier meta-analysis from the same group did find frequency effects, but the volume-equated version is the one that answers the question most people are actually asking. Once you control for how much work gets done, spreading it across more days does not by itself produce more.
Which means frequency is mostly a logistics variable. Pick the schedule that lets you complete the volume you intended, and stop looking for a magic number of days.
Why every-other-day beats a weekday split for me
It does not hide a long weekend. A Monday-Wednesday-Friday split gives you one day between two sessions and two days before the next, and that extra day stops registering as rest. Every other day makes the gap uniform and visible. I still end up training back to back occasionally when a day gets moved, but it is obvious when it happens instead of being baked into the plan.
It survives real life. Miss Wednesday on a weekday plan and you're now choosing between a doubled-up Thursday and a lost session. On an every-other-day plan a missed day just shifts the sequence. There is no "behind."
It rotates through the week. Sessions land on Saturdays and Tuesdays alike, so no single lift permanently owns the day I'm always tired.
Four days one week, three the next averages about three and a half, which is comfortably inside the range every frequency study operates in.
The honest costs
You cannot tell anyone when you train. No training partner, no standing gym date, no class. If your training is social, this is a bad fit and that alone might decide it.
It needs a rotation, not a weekday plan. My split is four days that cycle in order rather than a "Monday is chest" arrangement. If you think in weekdays you have to rewire that, and the app has to track where you are in the rotation rather than what day it is.
It drifts against weekends. Some weeks the heavy session lands on the day you had plans. You move it, and the sequence absorbs it.
What actually matters more
Frequency turned out to be the least interesting variable in my own training. Total volume, honest rest between sets, and progression that reads what happened rather than what the calendar said have all done more.
If every other day fits your life, it is a good schedule. If three fixed weekdays fits better, that is also a good schedule, and the volume-equated evidence says you are not giving anything up. Pick the one you will actually complete, then let the progression rules do the work.
