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Purpose: With the aging population facing an increased risk of ocular conditions such as glaucoma, age-related macular degeneration (AMD), and diabetic retinopathy, finding non-invasive methods to support eye health is essential. This meta-analysis aims to compare the effects of aerobic, isometric, and resistance exercises on visual acuity and overall eye health in the elderly, seeking to identify which type of exercise may be most beneficial for maintaining or improving eye health. Method: A systematic review and meta-analysis were conducted following standard guidelines. Electronic databases, including PubMed, Scopus, and Web of Science, were searched for relevant studies published between 2000 and 2023. The search included terms related to aerobic, isometric, and resistance exercises, visual acuity, intraocular pressure (IOP), retinal health, and elderly populations. Studies were screened and selected based on predefined inclusion criteria, focusing on research involving elderly participants and outcomes related to eye health. Results: A total of 15 studies met the inclusion criteria, encompassing 1,200 participants with a mean age of 68 years. The meta-analysis revealed that aerobic exercise significantly reduced intraocular pressure (mean difference = -2.5 mmHg, 95% CI: -3.2 to -1.8, p < 0.001) and improved retinal health markers (effect size = 0.35, 95% CI: 0.20 to 0.50, p < 0.01). Resistance exercise was associated with enhanced visual acuity (effect size = 0.28, 95% CI: 0.15 to 0.41, p < 0.01) and a reduction in the progression of AMD (relative risk = 0.70, 95% CI: 0.50 to 0.90, p < 0.05). Isometric exercises showed minimal impact on eye health compared to the other exercise types (effect size = 0.05, 95% CI: -0.10 to 0.20, p = 0.40). Conclusion: This meta-analysis supports the idea that aerobic and resistance exercises can protect visual acuity and overall eye health in the elderly, likely due to improved blood circulation, reduced oxidative stress, and enhanced retinal function. In contrast, isometric exercises showed minimal benefits, potentially due to their limited impact on systemic circulation. These findings suggest the importance of specific physical activities for mitigating age-related ocular disease risks, with implications for clinical and public health guidelines aimed at preventing visual decline in aging populations.

Objective: Plasma follistatin and leptin proteins are important indicators in energy and metabolism regulation that also affect body weight. The aim of this study was to investigate the effect of resistance training with and without blood flow restriction on serum follistatin and leptin levels in inactive obese girls. Materials and Methods: Thirty inactive obese girls with an age range of 20 to 28 years participated in this study. The subjects were randomly divided into 3 groups: resistance training with blood flow restriction and resistance training without blood flow restriction, and a control group (10 subjects in each group). Data analysis was performed using paired t-tests and one-way ANOVA at a significance level of less than 5%. Results: After 12 weeks of participation in sports activity, follistatin levels in both resistance training groups with and without blood flow restriction increased significantly after training (p<0.05). On the other hand, leptin levels decreased significantly in these groups after training interventions (p<0.05). Regarding the main effect of groups, the results showed that there was a significant difference between the types of resistance training and the control group in follistatin (P=0.036) and leptin (P=0.015) levels. Conclusion: The findings indicate that resistance training can lead to an increase in plasma follistatin levels and a decrease in leptin in inactive obese girls. It is recommended that obese individuals use such resistance training with blood flow restriction as a non-invasive, low-cost, and side-effect-free method to promote health and lose weight

Purpose: Multiple Sclerosis (MS) is a chronic neurological condition leading to muscle stiffness, spasticity, and reduced flexibility, particularly in the posterior chain muscles. Myofascial release (MFR), has shown promise in improving flexibility in various populations, but the cumulative effects of increasing the number of sessions have not been well-studied in individuals with MS. This study aimed to investigate the effects of a six-week myofascial stretching training program on the flexibility of posterior chain muscles in individuals with MS, with a focus on evaluating the cumulative effects of increasing the number of sessions. Method: A total of 30 female participants with MS were randomly assigned to one of two groups: a group receiving myofascial stretching training twice per week (n=15), and a group receiving training four times per week (n=15). Flexibility of the posterior chain muscles was assessed using the Sit and Reach (S&R) test at baseline, after 6 weeks of the intervention. Results: The results showed a significant improvement in S&R scores in both intervention groups. The group receiving training four times per week demonstrated greater flexibility improvements than the group receiving training twice per week, suggesting a cumulative effect of increasing the number of sessions. Conclusion: A six-week myofascial stretching training program can effectively improve the flexibility of posterior chain muscles in individuals with MS. Increasing the frequency of sessions from twice per week to four times per week leads to greater cumulative improvements in flexibility. These findings have important implications for the design of rehabilitation programs targeting flexibility in individuals with MS.

The pathophysiology of heat stress occurs when the body's environmental and physiological responses exceed its ability to maintain homeostasis. When internal heat signals or external factors raise body temperature beyond a certain limit that the cooling mechanisms can effectively manage, the resulting increase in core temperature triggers response pathways that themselves induce physiological stress. The primary response mechanisms to heat stress include sweating, peripheral vasodilation, and shivering as thermogenic responses—all of which are activated by elevated temperatures and may seem counterproductive to the body's requirements, yet they operate through a neuromuscular and hormonal feedback system. Genetic factors influence individual heat tolerance; for instance, certain populations have variations in heat shock proteins (HSP70) and ion channels (TRPV1, RYR1) that enhance their heat response and tolerance. Additionally, individuals with higher relative VO2 max levels demonstrate greater heat tolerance, as those who are physically trained exhibit more sudomotor activity and effective evaporative cooling compared to untrained individuals. Furthermore, individuals who acclimatize to heat over time develop improved thresholds for heat stress, enabling them to better regulate internal and cardiovascular temperature stresses during exposure. This knowledge is crucial for populations at risk and in situations where physical exertion is required in hot conditions.