Are We Underestimating the Affective Benefits of Exercise? an Experience Sampling Study of University Aerobics Participants
Lutz, Rafer, Lochbaum, Marc R., Carson, Tyler, Jackson, Staci, Greenwood, Mike, Byars, Allyn, Journal of Sport Behavior
There is considerable support for the ability of acute bouts of exercise to influence affective states (e.g., Arent, Landers, & Etnier, 2000; Landers & Petruzzello, 1994; Thayer, 1987a). Studies have generally shown that exercise increases states of positive affect or energetic arousal (Gauvin & Rejeski, 1993; Lutz, Lochbaum, & Turnbow, 2003; Thayer, 1987a), and reduces anxiety, tension, or negative affect (Breus & O'Connor, 1998; Kennedy & Newton, 1997; Petruzzello, Jones, & Tate, 1997; Thayer, 1987a). Interestingly, research has demonstrated that exercise may be similarly effective in the treatment of depression compared with other commonly-employed modalities such as selective-serotonin reuptake inhibitors (Dunn, Trivedi, Kampert, Clark, Chambliss, 2005). A limitation exists, however, in that most studies compare postexercise affect to preexercise affect rather than daily affect. This is problematic because the magnitude of the influence of exercise on affective states may be misrepresented if baseline measures are influenced by the laboratory situation or knowledge of impending exercise engagement, or if such baselines are simply different than the affect individuals experience on a daily basis. While several studies have examined affective states in naturalistic settings (Gauvin, Rejeski, & Norris, 1996; Giacobbi, Hausenblas, & Frye, 2005; Thayer, 1987a), only one known study (Petruzzello, 1995) has yet combined the common pre-post exercise methodology with a naturalistic assessment of affective states. The present investigation, therefore, sought to examine how average daily affect compares to affective states reported before, at the mid-point, and after an exercise session.
Closely related to the present question of interest, Petruzzello (1995) examined whether commonly-reported reductions in state anxiety after exercise might be due to a "sense of relief" that exercise is over. He recruited participants for a study to assess "coping strategies and psychological control" and, upon arrival in the laboratory, two resting baselines of heart rate and state anxiety (10-item State Anxiety Inventory, SAI; Spielberger, 1983) were taken. Next, participants were told that they would be required to run on a treadmill for 15 minutes and two more resting heart rate and state anxiety baselines were taken. There was no significant change in either heart rate or state anxiety comparing the baselines taken before revelation of the exercise requirement with those taken after this revelation. Additionally, Petruzzello had participants take four SAI's during the course of a 24-hr period outside the lab. The mean levels of state anxiety taken outside the lab were in fact slightly greater (Study 1 M = 16.3, SD = 5.0 & Study 2 M = 17.7, SD = 4.5) than the mean of the baseline SAI's taken in the lab (Study 1 M = 15.4, SD = 3.99 & Study 2 M = 16.1, SD = 4.3), though these were not significant differences. Based on these results, Petruzzello stated that it is unlikely that anxiety reduction following exercise is an artificial finding, due to a sense of relief that exercise is over.
At present, the "sense of relief" phenomenon investigated by Petruzzello (1995) does not appear to be an important factor related to the anxiolytic effects of exercise. One could make this case considering Petruzzello's findings, the relatively long-lasting (up to 2 hrs or more) anxiety-reducing effects of exercise (e.g., Raglin & Wilson, 1996), and the fact that anxiety-reduction occurs after a wide range of physical activities at low to moderate intensities (see Ekkekakis & Petruzzello, 1999) which wouldn't be expected to invoke a sense of relief upon completion. Still, research has not often addressed the possibility of a sense-of-relief occurring after exercise and it should not be ignored. Even if the sense-of-relief explanation for anxiety reduction is not valid, it is important to consider how exercise influences affect considering pre and postexercise affective states and how they may differ from an individual's "average" affective states. …