Answer to Question 1
Meta-analyses reveal a positive relationship between cardiovascular fitness and cognitive performance in older adults. For example, Colcombe and Kramer found that fitness training increased performance 0.5 SD standard deviations on average, regardless of the type of cognitive task, the training method, or participants' characteristics.. In a review of the relevant empirical literature, McCauley, Kramer, and Colcombe noted that although fitness effects were observed across a wide variety of tasks and cognitive processes, the effects were largest for those tasks that involved executive control (i.e., planning, scheduling, working memory, interference control, and task coordination) processes.. Executive control tasks are associated with memory and higher cortical functions.
Answer to Question 2
The social interaction hypothesis states that physical activity is often done with others and that social support and social rewards play a role in exercise-related mood enhancement. However, this hypothesis does not take into account the fact that exercise is often a solitary activity that is not always done in groups or with partners. If social interaction is a primary explanatory mechanism, then people who exercise in groups should have higher mood benefits than those who exercise at home alone. However, there is contradictory evidence for this hypothesis. For example, Blumenthal et al. found no significant differences in reduced depression scores for participants who were randomly assigned to a home exercise group when compared to those in a group exercise condition; both groups, however, showed benefits over placebo controls.
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