Behaviors minimizing energetic cost: A reward?

Dr. Boris Cheval - FNS – Ambizione 

Today one third of the adult population and 81% of the adolescent population fail to reach the recommended amounts of physical activity. This project aims to better understand why most individuals fail to exercise regularly despite their intention to be active. While the rewarding value of physical activity has been widely studied, its cost has been neglected. Yet, behaviors minimizing energetic cost (BMEC) have been critical during human evolution. Therefore, BMEC can easily be conceived as a reward. In particular, I hypothesize that individuals fail to exercise regularly because BMEC are rewarding, and as such activate competing automatic processes preventing physical activity implementation.

To accurately test the hypothesis that BMEC is a reward, participants will be conditioned to systematically associate neutral geometrical figures with different levels of energetic cost. These conditioned stimuli will be used to ensure that the tested constructs are solely related to different level of energetic cost. The current research plan includes 3 work packages and 6 studies. The work package 1 will investigate the effects of pure energetic-cost related stimuli on different types of automatic reactions including attention capture, affective reactions, and approach tendencies (Study 1a), and will test whether individual differences in physical activity level moderate these automatic reactions (Study 2a). The work package 2 will examine how the physiological state of the individual before (Study 2a) and during the experiment (Study 2b) moderate these multiple automatic regulatory reactions. Finally, the work package 3 will assess whether BMEC activate the brain regions typically involved in reward processing (Study 3a) and how individual differences in physical activity level can affect these brain activations (Study 3b).

If BMEC is a reward, impacts are substantial regarding several scientific and societal aspects. At the scientific level, all studies investigating behavioral and brain processes in sitting or lying position should take into account that participants are already potentially rewarded by this resting position. Additionally, if BMEC is a reward, this implies that the pandemic of physical inactivity is mainly driven by an automatic resistance to the intended engagement in physical activity. Scientists would therefore need reconsider the dominant approaches to exercise behaviors and integrate the fundamental principle pushing individuals to minimize energetic cost to better understand the mechanisms underlying this automatic resistance towards physical exertion. At the societal level, physical inactivity remains one of the leading risk factors for global mortality. Each year, physical inactivity is responsible for more than 5 million deaths worldwide. By improving the understanding of the psychological and neural mechanisms underlying the regulation of exercise behaviors, this proposal has the potential to open new possibilities to understand, and ultimately tackle, this important health problem.

Team