Jim Kwik recommends resistance training at least twice a week, ideally three full-body sessions with compound movements like farmer's carries and kettlebell swings. He connects strength training to brain health through "cognitive velocity" and suggests adding one 10-20 minute HIIT session weekly to sharpen mental processing speed.
Chapters
How should somebody think about doing resistance training? At the minimum, it should be 2 days a week. In an ideal world, it should be 3 days a week. Compound movements, things that involve your entire body. You're not gonna get bulky. We're not training to get better at exercise. We're training to get better at life. And resistance training, this is 3 days a week, full body exercises, compound movements, thinking about movements that have functional crossover. Specific example of that would be a farmer's carry. You can get 2 kettlebells and pick them up and walk them around. Around your block. You can do kettlebell swings, you can do overhead presses. And from a brain function perspective, there's this idea of cognitive velocity— speed of thinking, speed of processing. One of the things that seems to have influence on that is high-intensity interval training, which would be pushing yourself, moving faster than you want to. And you should do that at least once a week. It could be 10 to 20 minutes in the entire week of pushing oneself.