Author(s): VIDAL, L., PAGEAUX, B.2, BÉLARD, C.1, DUCHÉ, P.1, CHATAIN, C.1, GRUET, M.1, Institution: UNIVERSITÉ DE TOULON, Country: FRANCE, Abstract-ID: 1633

INTRODUCTION:
Prolonged engagement in demanding mental exertion is known to alter subsequent endurance performance [1] and the intention to engage in physical activity [2]. Young adults are exposed daily to prolonged engagement in video games and social networks. This exposure is known to be highly demanding and proposed to induce mental fatigue. Recent studies demonstrated the negative effects of mental fatigue on various physical performances [3]. In this context, this study aimed to test the effect of prolonged engagement in video games and smartphone scrolling on social networks (VGSS) on subsequent isometric endurance performance and intention to physical activity in young adults.
METHODS:
Thirty-eight young adults (13 female; 19±1y.o) participated in this randomized controlled crossover study. Following a familiarisation with all procedures, participants visited the laboratory twice. Participants engaged either in 90-min alternating between VGSS (experimental condition) or watching emotionally neutral documentaries (ND) for the same duration (control condition). Participants rated the perceived workload of each task with the NASA TLX scale. Mental fatigue was evaluated with changes in fatigue perception (visual analogue scale) during the cognitive tasks. To measure cognitive performance, participants performed a 2-Back test pre-post cognitive tasks. At the same time points, they also reported with the 6-20 Borg scale their intention to engage effort in a physical activity (i.e. 30-min cycling). Then, they performed an isometric contraction of the knee extensors at 20% of their maximal voluntary peak force, until exhaustion. Finally, 7 days of wrist-worn accelerometry were used to characterize physical activity levels.
RESULTS:
The NASA TLX scale confirmed the greater demand for engaging in VGSS compared to ND (p<.001). Perception of fatigue increased (p<.001) to a similar level at the end of the cognitive tasks, with no difference between conditions (p=.393), and no decrease in cognitive performance (ps>.416). Participants’ intention to engage in physical activity decreased (p<.001) regardless of the condition (p=.663). Time to exhaustion did not differ between both conditions (VGSS: 296±141s vs ND: 304±121s; p=.479).
CONCLUSION:
While the participants perceived the VGSS as more demanding than ND, engaging in VGSS did not induce a specific state of mental fatigue compared to the ND. Our preliminary results failed to replicate previous observations from the literature suggesting a specific negative impact of VGSS on subsequent endurance performance and intention to engage in physical activity. As a high level of physical activity and fitness increases resistance to fatigue, an exploratory analysis considering these factors will be performed to further confirm our results.
References:
[1] Pageaux and Lepers. 2018. https://doi.org/10.1016/bs.pbr.2018.10.004
[2] Brown and Bray. 2018. https://doi.org/10.1093/abm/kay052
[3] Fortes et al. 2020. https://doi.org/10.1080/02640414.2020.1715181