I loved @Schiendelman’s answer, and I believe that prioritizing mental and physical health is a prerequisite for tolerating frustration effectively. For me, it's been more about a change in practices and perspective.

For example, I never react in the moment to professional frustration beyond listening and asking sincere questions. I've learned that I need time to respond, and even to consider whether I should respond at all.

If I find myself awake at 4am ruminating about an aspect of my company or product, I remind myself that I may be taking it (and myself) a bit too seriously, and reassure myself that it can safely be tabled until tomorrow.

There's wisdom in the Serenity Prayer: "Grant me the serenity to accept the things I cannot change, courage to change the things I can, and wisdom to know the difference."

I have noticed that on the mornings where I do some exertion before anything else—a run, some yoga, etc.—that my ability to "receive" and process the things that come at me is so much better. It feels like there's a waiting room, whereas otherwise, whatever comes at me gets a 1:1 response.

Have you found weightlifting to be specifically beneficial, or is that just your morning workout of choice?

It is more beneficial than cardio in raising my base caloric burn, though I also like running and hiking when I can!

It takes less time each day than cardio for giving me the kind of focus and calm improvements I want.

It has a much bigger impact on physical appearance as well. Something I've learned is that more muscle mass really does translate to more respectful treatment from basically every other human in your life.