Chronic Exercise And Protein-Content Of A Single Meal Influence Hippocampal-Dependent Learning

Chronic aerobic exercise improves cognitive performance with benefits particularly evident for measures of hippocampal-dependent memory. Improvements in cognitive performance due to diet modification are also documented. However, the impact of individual meals on cognitive performance is less clear, and research exploring the potential combined benefits of exercise and diet is limited. PURPOSE: This pilot study was designed to evaluate the combined effect of chronic aerobic exercise and protein-content of an individual meal prior to a hippocampal-dependent cognitive task. METHODS: Male adult Sprague-Dawley rats (n=27) were randomly assigned to a 5 or 6-week forced exercise protocol (Ex) or to a sedentary control condition (Sed). Exercise (last hour of light cycle) duration and intensity were increased over a 4-wk period up to 60 min at 30 m/min and a 10.5% grade. The weekly exercise consisted of 2 days of rest after 5 days of exercise. Rats were on a feeding schedule consisting of a 30 min meal (20% daily calories) provided 60 min into the dark period and ad libidum access to chow the last 5 hrs of the dark cycle throughout. During the last week of exercise, rats memory was assessed 60 min after a low (15% casein) or high (50% casein) protein meal in a Barnes maze (a task requiring that rodents detect an escape hatch in a fixed location) on 4 consecutive days. RESULTS: Results showed that there was a main effect for days, F(3,69)=3.81, p