I'm the opposite. Never much liked sports, and when I am not held to a pace like a treadmill does, I'll not maintain enough heart rate elevation.

So, for me, if I don't get to the gym a couple of times a week, I fall well short of the NIH guidelines.

The full report is quite clear that heart rate elevation is the most significant population-wide contributor.to general health. 150 "points" per week, which you can in theory knock out with one long (~75 minutes) high-intensity work out.

Resistance training across all major muscle groups is secondary, and really only needs one set, on two separate days each week. Your don't need to build bulk or anything, just keep then fully active. Add some weight if you could do an extra set before exhaustion.

Stretching is good, in particular if you don't reach a range of motion, you are likely to lose it as you age, but no specific recommendations are given