A study on acute expectation effects on affective state and intention after a brief full-body workout in a student sample
Authors: Hösl Benedikt , Straif Julia , Niedermeier Martin , Kopp Martin 
Published: September 2024

Introduction & Purpose
Research shows that even short exercise programs can have positive effects on affective state (Focht, 2009), which in turn could have a positive influence on the intention to exercise in the future (Finne et al., 2022). The state of research in recent years also indicates that such benefits can be enhanced by manipulating expectations (Helfer et al., 2015). However, most of these studies on expectation effects were conducted in laboratory settings, meaning that the results are transferable to a natural context or everyday situations only to a limited extent. The aim of this study was therefore to examine whether the manipulation of affective expectations can influence affective state after physical activity in a more naturalistic setting; in addition, it was investigated whether the expectation manipulation has an effect on the intention for future exercise.
Methods
In an online experiment, 121 physically active students (25.58 ± 5.11 years), 70.2% female, were randomly assigned to either a ten-minute, virtually-guided whole-body workout (PA), a ten-minute, virtually-guided whole-body workout after manipulation of affective expectations via audio file (PA + EM), or a sedentary control intervention (CG). In the audio file, a purported speaker for the research team highlighted that recent research indicates that brief workouts would have particularly positive effects on stress experience and affective state. Pre- and post-intervention data, including affective state and intention, were collected using questionnaires, such as the Mood Survey Scales by Abele-Brehm and Brehm (1986).
Results
After controlling for the baseline level before the intervention via analyses of covariance (ANCOVAs), PA and PA + EM showed significantly more positive scores than CG in several parameters of affective state (e.g., scale Activation, Elation, Fatigue) after the intervention, in some scales (e.g., Affective Valence, Depression) only PA + EM differed significantly from CG. The mean scores in intention after the intervention did not differ significantly between PA + EM (27.00 ± 4.57), PA (27.41 ± 6.79), and CG (27.70 ± 5.78), p = .836.
Discussion
Even a short, virtually-guided workout can have strong positive effects on affective state. No direct effects of the expectation manipulation on affective state or intention were found. Possible reasons for this include ceiling effects in the participants’ expectations, or that the form of expectation manipulation used was less suitable for influencing the outcomes. However, in some affective parameters, the expectation manipulation was the decisive factor for the differences to the control group, so that more latent effects of the manipulation cannot be ruled out.
Conclusion
Even though no significant effects of the expectation manipulation were found, the results do not appear to be entirely unaffected by it. Also, because the differences found in affect could have a long-term effect on physical activity behavior, further research is needed in this field in order to be able to make more reliable statements. From a practical perspective, when designing or implementing interventions to increase physically active behavior, practitioners should be aware of the importance of the wording used when describing physical activity to their clients.
References
Abele-Brehm, A., & Brehm, W. (1986). Zur Konzeptualisierung und Messung von Befindlichkeit: Die Entwicklung der „Befindlichkeitsskalen“ (BFS) [The conceptualization and measurement of mood: The development of the “Mood Survey“]. Diagnostica, 32(3), 209-228.
Finne, E., Nigg, C., Weyland, S., Sauzet, O., Wienke, B., & Jekauc, D. (2022). Examining the role of affective states in relation to exercise intentions and participation in extra-curricular exercise classes at university: A repeated measurement observational study. Frontiers in Psychol, 13, Article 815466. https://doi.org/10.3389/fpsyg.2022.815466
Focht, B. C. (2009). Brief walks in outdoor and laboratory environments: Effects on affective responses, enjoyment, and intentions to walk for exercise. Research Quarterly for Exercise and Sport, 80(3), 611-620. https://doi.org/10.1080/02701367.2009.10599600
Helfer, S. G., Elhai, J. D., & Geers, A. L. (2015). Affect and exercise: Positive affective expectations can increase post-exercise mood and exercise intentions. Annals of Behavioral Medicine, 49(2), 269-279. https://doi.org/10.1007/s12160-014-9656-1