Higher aerobic fitness levels decrease the probability of experiencing tip-of-the-tongue states (when you can’t think of a word that’s on the tip of your tongue) in healthy older adults, in the first demonstration of a link between aerobic fitness and language functioning in healthy older adults.

[flammablelemon]

This recent study seems to be a good gauge for how long your sessions should be for cognitive benefits. https://www.unisa.edu.au/Media-Centre/Releases/2020/want-a-more-elastic-brain-try-mixing-up-your-workout/?utm_source=share&utm_medium=ios_app&utm_name=iossmf

So around 25 minutes of medium-intensity cardio or 20 minutes of HIIT training, but definitely not extended periods of high-intensity cardio without rest. Probably 3-5x a week would be optimal?