Virtual reality study suggests physical effort decreases in the perceived pleasantness of human faces

A new study has utilized virtual reality to demonstrate that moderate-to-vigorous effort influences the perceived pleasantness of human faces with neutral expressions. The new findings have recently been published in Psychology of Sport and Exercise.

The study authors were interested in deepening our understanding of how physical activity influences affective valence, meaning the positive or negative emotional tone of an event, object, or situation. The new research sought to test an assessment of affective valence that does not rely on self-report questionnaires.

“Exercise is unquestionably one of the most popular New Year’s resolutions made by millions of people. Unfortunately, this resolution often fails by the month of February,” said study author Boris Cheval, a neuropsychologist affiliated with the Swiss Center for Affective Sciences at the University of Geneva.

“Tackling this inability to translate the intention to be physically active into action is urgent if we want to stand a chance to slow down the pandemic of physical inactivity and meet the targeted 15% reduction of physical inactivity by 2030. Meanwhile, every six seconds, one individual dies of causes associated with physical inactivity (i.e., ~5.3 million people each year).”

“A recent consensus article, titled ‘The rise of affectivism‘, contends that modifying human behaviors cannot be done efficiently and durably without considering affective mechanisms,” Cheval continued. “An abundant and convincing literature shows that affects shape human behavior. Physical activity behavior is no exception – affective mechanisms have taken a prominent place in recent theories of physical activity, to the point that these mechanisms could be considered as essential to explain the gap between intention and action.”

“Experimental work in line with these theories has shown that experiencing positive affect during physical activity increases the likelihood of re-engaging in this behavior in the future. Despite these promising results, the literature investigating the role of affect during physical activity is limited. In particular, the gold standard to measure affective response during physical activity is based on self-reported scale, such as the Feeling Scale or the Empirical valence scale.”

“For example, the Feeling Scale is a single-item scale in which participants are asked to rate from -5 (I feel very bad) to +5 (I feel very good) how they feel right now, with the scale being repeatedly completed by the participant during a physical activity session,” Cheval explained. “Nonetheless, there are known limitations associated with self-reported measures that may lead to inaccuracies in the measurement of the subjective experiences of affect (e.g., social desirability bias, interpretation issues, inability to evaluate oneself).”

“So, the aim of the paper was to develop an indirect measure targeting the implicit affective valence elicited during physical effort.”

Cheval and his colleagues recruited 42 participants from the local community. The participants sat on an exercise bike and a virtual-reality headset (the HTC Vive Pro Eye) was placed on their head. While on the bicycle, the participants were presented with a series of realistic 3D faces in the virtual environment, which displayed three different expressions: anger, happiness, or neutral. The participants were asked to rate the pleasantness each face on a 9-point scale while cycling at five different levels of difficulty.

Happy faces were rated as the most pleasant, followed by neutral faces and angry faces. Importantly, the researchers found that increases in both perceived effort and actual effort were associated with decreases in the perceived pleasantness of neutral faces. However, this effect only emerged at moderate-to-high levels of perceived effort. The findings held after controlling for age, body mass index, and sex.

“We demonstrate that higher perceived effort was associated with an automatic decrease in the affective valence during physical activity,” Cheval told PsyPost. “In other words, these findings suggest that the affective response elicited during effort can be rather automatic and therefore hardly controllable.”

The findings could have important implications for efforts to increase physical activity. “As poor affective response may likely explain why many people intending to be physically active may struggle to re-engage in physical activity, this study also aims to stress (although not tested here) that people need to ensure positive affective experiences if they want to maintain their physical activity behavior across the long-term (see our argument in this paper that should be accepted soon in Journal of Sport and Health Science as they only requested changes in the format of the paper),” Cheval explained.

The findings come with a few caveats and areas for future research.

“It could be important to adjust the level actual effort to participants’ cardiorespiratory fitness to better disentangle the effect of actual effort and perceived effort on the affective experience,” Cheval said. “It is important in future studies to test the predictive validity of our measure (i.e., link between the implicit affective response and future physical activity). Finally, we are currently developing a biosensory model underpinning the emergence of affect during physical activity. It should allows to better understand the key biosensory mechanisms underlying these affects.”

The study, “Physical effort biases the perceived pleasantness of neutral faces: A Virtual Reality Study“, was authored by Boris Cheval, Silvio Maltagliati, Layan Fessler, Ata Farajzadeh, Sarah N. Ben Abdallah, François Vogt, Margaux Dubessy, Maël Lacour, Matthew W. Miller, David Sander, and Matthieu P. Boisgontier.

© PsyPost