Physical Exercise Intensity During Submersion Selectively Affects Executive Functions

Abstract

Objective: The intact cognitive processing capacity in highly demanding and dynamically changing situations (e.g., in extreme environmental conditions) is of central relevance for personal safety. This study therefore investigated whether underwater physical exercise (PE) affected cognitive performance by comparing these effects during underwater fin-swimming as opposed to inactivity under normal environmental conditions. Background: Although acute bouts of PE can modulate cognitive performance under highly controlled and standardized laboratory conditions, no previous study has determined whether PE acutely modulates cognitive performance in non-laboratory testing conditions involving extreme environments (e.g., underwater). Method: A total of 27 healthy volunteers (16 males and 11 females; 28.9 ± 7.4 years of age) participated in two experiments involving either moderate or high PE intensity. A PRE/POST crossover design was employed among participants while performing cognitive tests in a counterbalanced order (i.e., before and after 20 min of PE in submersion [WET] and once before and after inactivity [DRY] while in the laboratory). Cognitive performance was measured as a combination of executive functions through the Eriksen Flanker (inhibition) and Two-Back (working memory) Tasks using an underwater tablet computer. Results: ANOVAs revealed enhanced reaction times only in the Flanker test after moderate PE for the WET condition. No other effects were detected. Conclusion: These findings indicate that cognitive performance is exercise-intensity-dependent with enhanced effects during moderate PE, even in extreme environments (i.e., underwater). Application: These results should be relevant in recreational and occupational contexts involving underwater activity and may also apply to microgravity (e.g., during extra-vehicular activities). Description This study compared the acute effects of physical exercise (PE) on cognitive performance in an underwater environment while participants fin-swam with SCUBA (self-contained underwater breathing apparatus) gear. Findings revealed that 20 min of moderate PE positively affected cognitive performance (i.e., inhibitory control ability). However, no changes were observed after high-intensity exercise.

Exercise-Related Effects on Executive Functions During a Simulated Underwater Extravehicular Activity

“…This work concentrates on investigating executive functions (EFs) that are considered cognitive processes, subserving higher goal-directing behavior (Friedman & Miyake, 2017). Tasks for EFs are easily comprehensible and offer a standardized and time-efficient way to investigate cognitive performance, even in extreme environments like underwater (Möller et al, 2021). EFs’ well-established model of unity and diversity describes response inhibition , switching, and updating as a pattern of shared but distinct functions.…”

“…We know from our recent study that fin-swimming exercise at 5 meters (m) water depth in a moderate exercise intensity of 20-min duration has a positive effect on inhibition (Möller et al, 2021). This confirms that shallow water immersion per se does not necessarily negatively impact EFs (Steinberg & Doppelmayr, 2017).…”

“…This confirms that shallow water immersion per se does not necessarily negatively impact EFs (Steinberg & Doppelmayr, 2017). It also suggests that moderate exercise intensity’s well-known positive effect on cognitive performance persists in an underwater environment (Möller et al, 2021). However, the influence on the combination of a change in exercise modality and the environmental features (i.e., upper-limb versus lower-limb exercise underwater) has not been addressed so far, limiting a transfer to EVA.…”

An Updated Narrative Review on Ergometric Systems Applied to Date in Assessing Divers’ Fitness

“…Nevertheless, we suggest that the fit2dive test also be used to perform scientific studies. These could further extent the knowledge on topics such as the relation between exercise intensity and cognitive competences [53] or on the effects of oxygen-enriched air on physiological variables (Zenske et al, 2019).…”

Effects of High-Intensity Interval Training on Executive Functions in College Students: Evidence from Different Doses

“…Moeller’s study has shown that exercise intensity can effectively affect the EF of individuals. In Moeller’s study, moderate-intensity physical exercise had a positive effect on inhibition control, while high-intensity physical exercise had no effect on inhibition control [ 16 ].…”