There are MANY reasons to change up a workout. The fact that it’s April 1st should not be one of them.
Ahh, the “Get a New Workout Every Month Club.”
New and prospective clients like the sound of it. I even flirted with it briefly in my group training, since it’s much easier to plan group workouts in advance.
..but I switched back to 6-8 weeks within a month. The results are just demonstrably better. Most lifters are just hitting their stride by week 3 or 4: they KNOW the workout, are used to the exercises, the flow, and most importantly their real limits in terms of loads.
But if you change a workout after week 4, you basically jump ship right when it’s starting to get productive.
Longer phases also give you time to do more productive WEEKLY changes in terms of break-in weeks, higher and lower volume weeks, and high-intensity weeks. But with only four weeks to work with you simply don’t have the space to do much in that regard—at least not productively.
Now, there are plenty of exceptions to the 6-8 weeks average, of course:
For example, if you are working out 4-5 days a week but repeating only 2-3 different workouts, then, sure, you’ll rack up six or more exposures to each different workout within four weeks. You can probably even feel that yourself in the workouts if things get repetitive. Here, changing after a month can make a lot of sense.
Conversely, if a workout and the larger program are still delivering after 8+ weeks (i.e., you’re adding weight or reps to most lifts on a reasonably consistent basis) then you’d be crazy to change it. Ride the wave. What you can even do is sub out the lifts that are plateaued and keep rolling.
Heck, depending on how advanced you are, even if a few lifts are stalling, I might still just keep things the same for awhile. As you get more advanced, adding weight to even a small number of important lifts is progress. Don’t fix what ain’t broken.
More broadly, there are many ways beyond just swapping out the entire program that you can do to spritz up a productive program that is starting to stall: change the sets, the reps, the rest intervals, the tempos (speed and mid rep pauses), even the order of exercises.
More than anything: focus on progress and not entertainment or arbitrary calendar dates.
If you read ’em over again, you’ll notice that this is what the exceptions have in common. They focus on progress, not arbitrary deadlines or even second-order indicators of progress.
It’s harder to do this because there are no clear rules (and so you open yourself up to doubt and mind games) but long-term it offers better results.