There is a general consensus in the literature that exercise improves affect. A meta-analysis of 158 studies published from 1979 to 2005 on the effects of acute exercise on positive affect concluded that exercise increases positive mood (Reed and Ones 2006), and there is evidence that acute exercise at intensities below the ventilatory or lactate thresholds can increase self-reported positive affect (Ekkekakis, Parfitt, and Petruzzello 2011). Mood benefits of acute exercise have been found for clinical populations (e.g., type 2 diabetes: Kopp et al. 2012; spinal cord injury: Martin Ginis and Latimer 2007). In addition, daily positive mood but not negative mood has been associated with objectively measured physical activity (Poole et al. 2011). But as already discussed, it is prudent to be cautious about overgeneralizing the benefits in mood and emotional states without considering some of the moderating variables, such as exercise history, task characteristics, and the environment.
Generally, regular exercisers compared with nonexercisers have greater mood enhancement after a single bout of exercise (e.g., Hoffman and Hoffman 2008). Reed and Ones (2006) showed consistently positive effects of acute exercise at low intensities, durations up to 35 min, for low to moderate exercise doses. In a study comparing objectively measured physical activity with daily mood, light and moderate physical activities were also associated with positive daily affect, but vigorous activity was not (Poole et al. 2011).
Rudolph and Kim (1996) measured mood responses to aerobic dance, soccer, tennis, and bowling in a sample of 108 physical education students at a Korean university. The Subjective Exercise Experiences Scale was administered before and after the activity. Positive mood was enhanced in students participating in aerobic dance and soccer. There were no changes in negative mood or in the moods of tennis players or bowlers. However, participants self-selected into the various exercise modes, and a randomized trial would provide more clarification of the role of exercise task in affective response.
Acute psychological responses to exercise can be affected by factors in the physical and social environment, such as temperature and humidity, odors, and the presence of others. For example, sedentary women exercised on a stationary cycle at moderate intensity based on RPE for 20 min with and without others in a mirrored or nonmirrored setting (Martin Ginis, Burke, and Gauvin 2007). Feeling states were measured by the Exercise-Induced Feeling Inventory before, during, and after exercise. Revitalization increased significantly less and fatigue increased more for women in the mirrored room with others compared to women in the other three conditions when controlling for body mass index (BMI). The responses to exercising with others in front of mirrors indicates the importance of considering environmental factors in analyzing the effects of exercise on mood.
Increases in positive mood have been found in youth sport participants after a game, but the improved mood seemed to be largely determined by the perception of achievement and the matching of skills against a realistic challenge (Wankel and Sefton 1989). One study of college-age participants showed that mood changes after running exercise were not influenced by competition (O’Connor, Carda, and Graf 1991).
A review of studies that used the POMS concluded that the evidence supports associations between acute physical activity and improved mood among nonclinical populations and between chronic exercise and improved mood among clinical populations (Berger and Motl 2000). The POMS has also been employed to identify social or cognitive explanations for mood alteration after exercise. However, currently there is no conclusive evidence identifying a single explanation or clustering of explanations that consistently mediates or moderates the association between exercise and mood change, although researchers are exploring a variety of possible explanations. For example, regular exercisers reported mood before and after 10 min of self-paced jogging, and were also asked after exercise to recall their preexercise mood (Anderson and Brice 2011). Mood as measured by the total mood disturbance (TMD) of the Incredibly Short Profile of Mood States (ISP) increased significantly and compared to the no-exercise control group. In addition, the recalled preexercise mood was favorably distorted to indicate mood enhancement. That is, their recalled preexercise mood was worse than actually reported before exercise, which gave a perceived augmented mood benefit of the acute exercise bout. Additional research is needed to determine the reasons for this memory distortion, such as current mood states and expectations of mood benefits from exercise.
We usually think about how exercise can improve positive mood and affect in the short term, but there is also evidence that exercise can reduce negative moods, such as anxiety and even obsessive-compulsive disorder symptoms (Abrantes et al. 2009), and can have effects beyond the exercise session. For example, 30 minutes of moderate-intensity cycling exercise reduced angry mood in college men who scored high in trait-anger and mitigated the increase in anger that was induced by viewing emotional pictures, but it did not alter the intensity of angry emotional responses during picture viewing (Thom et al. 2012). Thus, even though exercise didn’t affect the acute experience of an angry emotion, it provided a prophylaxis against angry feelings elicited up to 45 minutes later. Another study used guided imagery to induce an upset or angry mood and reported a reduction in state anger after a session of resistance exercise, but that change was not greater than seen after quiet rest (Bartholomew 1999).
Bryne and Bryne (1993) reviewed 30 studies published since 1975 on the effects of exercise training on mood adjustment, such as depression, anxiety, and other states of disturbed mood. Ten of the studies evaluated mood changes in nonclinical populations and showed significant improvements in mood that were not related to changes in fitness. Overall, 90% of the studies reviewed supported the contention that exercise improves mood. Reed and Buck (2009) reviewed 105 studies of regular aerobic exercise and positive affect published from 1980 to 2008 and reported a moderate beneficial effect on self-reported affect with the optimal program at a low intensity for 30 to 35 minutes, 3 to 5 days per week for 10 to 12 weeks. Several randomized clinical trials have shown positive effects on mood and quality of life in clinical populations, such as women being treated for breast cancer (e.g., Yang et al. 2011; Mutrie et al. 2007), people with multiple sclerosis (Dalgas et al. 2010), and people with traumatic brain injury (Driver and Ede 2009). There is also some evidence that mood improvements are related to exercise adherence. For example, the Profile of Mood States-Short Form and other psychological measures were administered to 173 obese women at the beginning and end of a 6-month moderate-intensity exercise intervention (Annesi et al. 2011). Mood significantly improved, and changes in mood and body satisfaction but not self-efficacy contributed uniquely to the variance in exercise session attendance, which was significantly related to changes in BMI.
Additional training studies have been generally supportive of positive effects of exercise on mood for various populations, although training intensity has had mixed effects. Mood was improved in initially sedentary older women after a 12-week strength training program (Tsutsumi et al. 1998). Both high-intensity and moderate-intensity strength training groups significantly improved positive mood and demonstrated some decrease in tension and state anxiety, although support for moderate intensity was greater. The greatest improvements in affect were found in young active aerobic exercisers who were randomized to a moderate-intensity resistance training program; those training at high intensity had the greatest decrements in affect, and those training at low intensity experienced no beneficial changes in affect (Etnier et al.
Mood was monitored before and after each exercise class over a 7-week exercise program in four self-selected exercise groups (Steinberg et al. 1998). Positive mood increased and negative mood decreased during each class, but favorable mood from exercise diminished by the following week. There seemed to be a persistent, acute effect that has also been demonstrated with some of the positive physiological effects