College students (N = 90) were randomly assigned to participate in vigorous, moderate or no physical exercise and vocabulary recall and comprehension learning activities under varying conditions to assess whether or not increased intensities of exercise, performed either before a vocabulary recall and comprehension learning activity (i.e., proactive effect) or after a vocabulary recall and comprehension learning activity (i.e., reactive effect), would improve vocabulary recall and comprehension. The results demonstrated that performing exercise at a vigorous intensity before or after rehearsing for a vocabulary comprehension test improved test results. [ABSTRACT FROM AUTHOR]