Volume 32, Issue 1 (3-2025)
RJMS 2025, 32(1): 1-11 |
Back to browse issues page
Department of Physical Education, Farhangian University, P.O. Box 14665-889, Tehran, Iran. , S.Samaie@cfu.ac.ir
Abstract: (196 Views)
Background & Aims: Anxiety is one of the most prevalent psychiatric disorders worldwide, characterized by excessive fear, worry, and behavioral disturbances that can significantly impair daily functioning and quality of life. Numerous studies have demonstrated that both genetic and environmental factors contribute to the onset and severity of anxiety disorders, with lifestyle choices playing a particularly crucial role. Among these factors, dietary habits, especially the consumption of high-fat diets, have received considerable attention in recent years. High-fat diets are commonly associated with obesity, metabolic disturbances, and neurochemical alterations that can directly or indirectly influence the central nervous system. Experimental studies on rodents have indicated that prolonged exposure to diets rich in saturated and trans fats may lead to increased levels of systemic and neural inflammation, alterations in neurotransmitter systems including serotonin and dopamine, oxidative stress, and dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis. Each of these mechanisms has been implicated in the pathophysiology of anxiety, suggesting a strong link between high-fat diet consumption and the emergence of anxiety-like behaviors. Physical activity, on the other hand, has been widely recognized as a protective factor against the development of anxiety. Aerobic exercises, including swimming, can induce a variety of neurophysiological and behavioral changes, such as enhanced neurogenesis, increased expression of brain-derived neurotrophic factor (BDNF), improved neurotransmitter balance, and reduced oxidative stress and inflammation in critical brain regions, such as the hippocampus and amygdala. Moreover, regular exercise has been shown to modulate HPA axis activity, reduce corticosterone levels, and improve overall stress resilience. These effects make exercise an attractive non-pharmacological intervention for mitigating anxiety and its underlying neurobiological disturbances. Despite growing evidence of the anxiolytic effects of physical activity, relatively few studies have examined the specific impact of swimming exercise on anxiety induced by high-fat diet consumption. Swimming, as a low-impact, full-body aerobic exercise, presents unique physiological and behavioral stimuli that may influence both central and peripheral mechanisms underlying anxiety. Considering the rising prevalence of high-fat dietary consumption and lifestyle-related mental health issues, investigating the role of swimming exercise in alleviating diet-induced anxiety is of significant scientific and clinical interest. Therefore, the present study aimed to explore the effects of a four-week swimming exercise program on anxiety levels in male Wistar rats subjected to a high-fat diet, using validated behavioral assays to quantify anxiety-like behaviors and evaluate the potential protective role of exercise against diet-induced emotional disturbances.
Methods: This experimental study was conducted on 24 male Wistar rats, which were randomly assigned to three groups: healthy control, high-fat diet control, and high-fat diet with swimming exercise. The swimming intervention was performed for four weeks, five days per week. To induce anxiety associated with a high-fat diet, the animals were fed a diet containing 40% fat for four weeks. Anxiety-related behaviors were assessed using the Open Field Test and the Light–Dark Box Test. Data were analyzed using one-way ANOVA followed by Tukey’s post hoc test.
Results: The analysis revealed significant differences among the groups in anxiety-related measures. The high-fat diet reduced the time spent and the number of entries into central and light areas, indicating anxiety-like behaviors, while swimming exercise significantly mitigated these negative effects. Overall, the high-fat diet increased anxiety, whereas swimming was effective in counteracting its impact.
Conclusion: The findings of the present study provide robust evidence that a high-fat diet induces significant anxiety-like behaviors in male Wistar rats. Animals subjected to a diet containing 40% fat exhibited reduced time spent and fewer entries into the central area of the open field test as well as decreased exploration of the light compartment in the light–dark box test. These behavioral patterns are indicative of elevated anxiety levels, consistent with prior research suggesting that high-fat diets can promote neuroinflammation, oxidative stress, neurotransmitter imbalances, and dysregulation of the hypothalamic-pituitary-adrenal axis. Collectively, these physiological changes likely contribute to the observed behavioral manifestations and underline the complex interplay between dietary intake and mental health. Importantly, the introduction of a structured swimming exercise program for four weeks effectively mitigated the anxiety-like behaviors associated with the high-fat diet. Rats in the exercise group displayed increased time and frequency of entry into both central and light areas, suggesting improved exploratory behavior and reduced anxiety. This finding supports the notion that aerobic exercise, particularly swimming, can act as a neuroprotective intervention capable of counteracting the adverse effects of poor dietary habits on emotional regulation. Mechanistically, swimming exercise is believed to enhance brain-derived neurotrophic factor (BDNF) expression, promote neurogenesis, balance neurotransmitter levels, reduce oxidative stress, and normalize HPA axis activity, thereby improving stress resilience and behavioral outcomes. These results align with previous studies highlighting the anxiolytic potential of regular physical activity and suggest that swimming may serve as an effective, non-pharmacological strategy to prevent or attenuate diet-induced anxiety. Overall, the current study emphasizes the significant impact of lifestyle factors on mental health, demonstrating that a high-fat diet can act as a potent stressor that promotes anxiety, while structured aerobic exercise can provide substantial protective benefits. These findings have important implications not only for understanding the neurobehavioral consequences of unhealthy dietary patterns but also for developing practical interventions aimed at improving mental health outcomes through non-pharmacological means. Given the increasing prevalence of high-fat diets and associated psychological disorders, the study underscores the potential utility of incorporating regular swimming or other aerobic exercises into preventive and therapeutic strategies to enhance emotional well-being and reduce anxiety risk.
Methods: This experimental study was conducted on 24 male Wistar rats, which were randomly assigned to three groups: healthy control, high-fat diet control, and high-fat diet with swimming exercise. The swimming intervention was performed for four weeks, five days per week. To induce anxiety associated with a high-fat diet, the animals were fed a diet containing 40% fat for four weeks. Anxiety-related behaviors were assessed using the Open Field Test and the Light–Dark Box Test. Data were analyzed using one-way ANOVA followed by Tukey’s post hoc test.
Results: The analysis revealed significant differences among the groups in anxiety-related measures. The high-fat diet reduced the time spent and the number of entries into central and light areas, indicating anxiety-like behaviors, while swimming exercise significantly mitigated these negative effects. Overall, the high-fat diet increased anxiety, whereas swimming was effective in counteracting its impact.
Conclusion: The findings of the present study provide robust evidence that a high-fat diet induces significant anxiety-like behaviors in male Wistar rats. Animals subjected to a diet containing 40% fat exhibited reduced time spent and fewer entries into the central area of the open field test as well as decreased exploration of the light compartment in the light–dark box test. These behavioral patterns are indicative of elevated anxiety levels, consistent with prior research suggesting that high-fat diets can promote neuroinflammation, oxidative stress, neurotransmitter imbalances, and dysregulation of the hypothalamic-pituitary-adrenal axis. Collectively, these physiological changes likely contribute to the observed behavioral manifestations and underline the complex interplay between dietary intake and mental health. Importantly, the introduction of a structured swimming exercise program for four weeks effectively mitigated the anxiety-like behaviors associated with the high-fat diet. Rats in the exercise group displayed increased time and frequency of entry into both central and light areas, suggesting improved exploratory behavior and reduced anxiety. This finding supports the notion that aerobic exercise, particularly swimming, can act as a neuroprotective intervention capable of counteracting the adverse effects of poor dietary habits on emotional regulation. Mechanistically, swimming exercise is believed to enhance brain-derived neurotrophic factor (BDNF) expression, promote neurogenesis, balance neurotransmitter levels, reduce oxidative stress, and normalize HPA axis activity, thereby improving stress resilience and behavioral outcomes. These results align with previous studies highlighting the anxiolytic potential of regular physical activity and suggest that swimming may serve as an effective, non-pharmacological strategy to prevent or attenuate diet-induced anxiety. Overall, the current study emphasizes the significant impact of lifestyle factors on mental health, demonstrating that a high-fat diet can act as a potent stressor that promotes anxiety, while structured aerobic exercise can provide substantial protective benefits. These findings have important implications not only for understanding the neurobehavioral consequences of unhealthy dietary patterns but also for developing practical interventions aimed at improving mental health outcomes through non-pharmacological means. Given the increasing prevalence of high-fat diets and associated psychological disorders, the study underscores the potential utility of incorporating regular swimming or other aerobic exercises into preventive and therapeutic strategies to enhance emotional well-being and reduce anxiety risk.
Type of Study: Research |
Subject:
Clinical Psychiatry