Even the teensiest, tiniest, barely measurable amount of physical activity improves brain function—not as much as the HIIT mentioned previously, but it is significant and it matters. The very largest improvements we’ve seen for reducing risks of cardiovascular disease and diabetes, and improving memory, come not from moderately active people who engage in a more systematic and intense program, but from sedentary people who engage in the barest minimum of physical activity—even just getting up and walking a bit.
