Long-term complete fasting (≥ 4 days) is an extreme condition which may happen in emergent situations, requiring exerted cognitive functioning and maintain strength to solve problems. However, there is still no clear understanding how long-term fasting and physical activities affect people’s cognitive functions and their mental states. In the current study, 22 healthy participants completed a 28-day experiment (7 females and 15 males; age: 41 ± 7 years old; BMI: 24.84 ± 2.52).
The whole experiment includes 3-day Baseline, 15-day Complete Fasting, 5-day Caloric Restriction and 5-day Full Recovery phases. Participants were randomly assigned into three groups with gender and BMI balanced across groups: Group EM with supervised moderate intensity of running (= 5 km/h) during Complete Fasting (2 F and 5 M; age: 40 ± 8; BMI: 25.40 ± 3.04); Group EL with supervised light intensity of running (= 3 km/h; 3 F and 5 M; age: 41 ± 7; BMI: 25.19 ± 2.62); Group CN without any exercise (2 F and 5 M; age: 43 ± 7; BMI: 23.89 ± 1.84). During the whole experiment, Go/No-go, Time Perception and Auditory Serial Reaction Time tasks were used to track participants’ cognitive functions and visual analogue scale was used to measure their mental states.
Results showed that fasting impaired executive and learning functions, and the inclusion of exercises further impaired the learning function. However, this cognitive decrease in inhibitory control due to fasting was not a linear trend but rather followed a double hump pattern, which may reflect the influence of metabolic changes from glucose to ketone. Additionally, fasting increased subjective feelings of sleepiness and decreased calmness, and no significant differences were observed among exercise groups.
This study is the first to combine long-term complete fasting and exercises, offering insights into fasting protocols and survival strategies in food-shortage emergencies. We thank all of the participants who completed the tasks involved in this study. We also thank Ruonan Mo for data organizing.
This research project was supported by the Advanced Space Medico-Engineering Research Project of China (BJH22WS1J002). Cognitive Science and Allied Health School, Beijing Language and Culture University, Beijing, 100083, China School of Humanties and Social Sciences, Beihang University, Beijing, 100191, China Zhirui Zhou, Qisong Yue, Yang Liu & Ruilin Wu Centre for Human Brain Health, School of Psychology, University of Birmingham, Birmingham, B15 2TT, UK Faculty of Medicine and Department of Social Neuroscience, Ruhr Universitat Bochum, 44801, Bochum, Germany State Key Laboratory of Space Medicine, China Astronaut Research and Training Center, Beijing, 100094, China Hongyu Zhang, Zhongquan Dai & Yinghui Li Correspondence to Qianying Ma, Zhongquan Dai or Ruilin Wu. The authors declare no competing interests.
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Below is the link to the electronic supplementary material. Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material.
Extract — continue reading at the source.
