“I’d love help in increasing my one arm dumbbell overhead press.”
While more details certainly would have helped me give more directed information, I can still talk about this in a more general way.
Pavel Tsatsouline popularized an old Russian saying:
“To Press a Lot You Must Press a Lot”
What this means is that to press a lot (i.e. to be able to press more weight) you need to press a lot (i.e. more volume and frequency).
The fact is that different parts of the body respond somewhat different to different approaches to training. While many people can get by on a low volume approach for some of the bigger muscles, like doing squats for the legs, the shoulders and triceps may need a bit more.
While 5×5 may work in the beginning for this, it won’t work for too long.
You can press every single day, if you keep the intensity and volume in check. You can also do some big volume workouts, with less frequency.
And in many cases, working with several different types of pressing can be beneficial too. What will help best depends on your weakest link. Some options include kettlebell press, barbell military press, push press, side press, partials, isometrics, cable press, handstand pushup and more.
The famous bodybuilder, before steroids got involved, John Grimek worked up to supporting 1000 lbs. overhead. With that kind of strength, you can bet he could press a heavy dumbbell overhead.
Regardless of how you’re doing it, if you approach it in a progressive training format, getting a stronger press should only be a matter of time.
There’s also the mental approach, which fits in alignment with that saying too.
All those mental reps translate to the physical reality too.
I’ve seen it happen time and again.