A growing body of research supports the idea that exercise can help boost cognition, especially moderate-to-vigorous aerobic exercise. In one example, researchers found that, for older people, time spent in moderate-to-vigorous cardiovascular exercise was positively correlated with increases in “fluid” intelligence—processing speed, memory, and reasoning. In the same study, sedentary time was correlated with boosts in “crystallized” intelligence, such as vocabulary development. Light physical activity, however, provided little cognitive benefit.