Some fitness guru that I follow on the internet—I think it was Andrew Huberman, although it might have been Andy Galpin—suggested that the optimal ratio of resistance and endurance training was 3-to-2—but also suggested that which one is emphasized should switch after some number of months.
So, you might combine three strength-training workouts per week with two endurance workouts per week for some number of months, and then reverse the ratio and go with three endurance workouts per week combined with two strength-training workouts per week.
This is interesting to me mainly because I seem to intuitively be doing exactly that. All through 2020 I was emphasizing resistance exercise (often 4 workouts per week), and limited myself to a single run most weeks. (Due in particular to a sore foot, but also just because it felt right.) I generally included an HIIT session most weeks—so also endurance training, even if not long steady-state training.
Early in 2021 I had made a plan to repeat Anthony Arvanitakis’s Superhero Bodyweight Workout, which I’d used the year before to good effect. I even bought the latest version, which seemed slightly better. But then a minor medical issue meant I had to defer the super-intense workouts that it called for. Once the medical issue was resolved I figured I’d get back to it, but as the year progressed I started feeling like running more and longer. My foot was no longer troubling me, and I always enjoy long runs.
I found myself doing less lifting and more running. Just lately it occurred to me that what I wanted to do was three runs per week, and maybe just two lifting sessions—which would be nicely in accordance with the suggested adjustment in workout ratios.
So that’s my plan for the rest of the winter—three runs per week, with just two lifting session. Then maybe in the spring I’ll switch back and reemphasize lifting.