(1) Background: The aim of this study was to assess the impact of multi-strain probiotic supplementation on the physical capacity and selected health indicators related to the exercise capacity of competitive road cyclists such as body composition, markers of intestinal permeability, pro- and anti-inflammatory markers, and anti-/pro-oxidant potential. (2) Methods: The group comprised 26 competitive road cyclists aged between 18 and 26. The study was a 4-month double-blind, random-assignment, parallel-group, and placebo-controlled trial. The measurements of physical capacity in the exercise tests of the anaerobic Wingate test (the level of total work volume, maximal anaerobic power, average power per revolution, mean time to achieve maximal anaerobic power, and time to maintain maximal anaerobic power) and the aerobic test using a cycle ergometer (maximum oxygen uptake, exercise duration, maximum load power, and maximal heart rate) were repeated after one, three, and four months. (3) Results: The probiotic supplementation resulted in increased levels of the relative magnitude of maximal oxygen uptake (65.28 vs. 69.18), the duration of training until failure (14.35 vs. 15.65), the load on the ergometer (5.11 vs. 5.36), and the degree of decrease in heart rate (193.3 vs. 188.6) together with a feeling of less discomfort during the exercise test (Borg scale) (19.38 vs. 18.43), confirming the beneficial effect of probiotics on the cyclists’ aerobic capacity during exercise. The probiotic supplementation produces no effects on the anaerobic capacity and body composition of the athletes, except for an observed increase in muscle mass. The concentration of zonulin in the stool mass decreased as a result of the probiotic therapy (81.2 vs. 25.21), and α1-atitrypsin was maintained at a similar level during the experiment (0.95 vs. 1.05), indicating a sealing of the intestinal barrier and beneficial changes in the cyclists’ intestinal function. The supplementation resulted in a reduction in the concentrations of: tumor necrosis factor TNF-α after the aerobic (13.88 vs. 9.75) and anaerobic tests (8.54 vs. 6.8), IL-6 before (1.2 vs. 0.86) and after the anaerobic test (1.47 vs. 0.97), IL-10 before the anaerobic test (0.70 vs. 0.44), and the total oxidative status (TOS) of the blood plasma before (663.7 vs. 484.6) and after the anaerobic test (643.1 vs. 435.9). (4) Conclusions: The probiotic supplementation resulted in increased levels of the cyclists’ aerobic capacity and their maintenance of anaerobic capacity and positively affected selected health indicators related to the exercise capacity of competitive road cyclists.

Appropriate nutritional preparation for a high-mountain expedition can contribute to the prevention of nutritional deficiencies affecting the deterioration of health and performance. The aim of the study was to analyze the dietary habits, supplementation and nutritional value of diets of high mountain climbers. The study group consisted of 28 men (average age 33.12 ± 5.96 years), taking part in summer mountaineering expeditions at an altitude above 3000 m above sea level, lasting at least 3 weeks. Food groups consumed with low frequency during the expedition include vegetables, fruits, eggs, milk and milk products, butter and cream, fish and meat. The energy demand of the study participants was 4559.5 ± 425 kcal, and the energy supply was 2776.8 ± 878 kcal. The participants provided 79.6 ± 18.5 g of protein (1.1 ± 0.3 g protein/kg bw), 374.0 ± 164.5 g of carbohydrates (5.3 ± 2.5 g/kg bw) and 110.7 ± 31.7 g of fat (1.6 ± 0.5 g/kg bw) in the diet. The climbers’ diet was low in calories, the protein supply was too low, and the fat supply was too high. There is a need to develop nutritional and supplementation recommendations that would serve as guidelines for climbers, improving their well-being and exercise capacity in severe high-mountain conditions, which would take their individual taste preferences into account.

The Paleo diet (PD) involves a restriction of carbohydrates and increased fat content (35% energy from carbohydrates, 35% energy from fats and 30% energy from protein). The aim of this study was to examine the effect of the PD on body composition, concentration of carbohydrates and lipids, as well as insulin, irisin, adiponectin and leptin in the blood. A total of 25 handball players were assigned to two groups: 14 in the experimental group (PD) and 11 in the control group (CD), using a PD and a rational diet, respectively. Analysis of body mass and body composition (body mass index, fat mass, lean body mass, fat-free mass, muscle mass, bone mineral content and bone mineral density), as well as blood concentration of metabolism markers (glucose, insulin, total cholesterol, HDL-cholesterol, non-HDL-cholesterol, LDL-cholesterol, triglycerides, free fatty acids, β-hydroxybutyrate, irisin, adiponectin and leptin), were determined at the beginning and after 4 and 8 weeks of nutritional intervention. Body mass was lower (p < 0.01), and adiponectin blood concentration was higher (p = 0.03) in the PD group at the end of the intervention. There were no changes (p ≥ 0.05) in body composition and blood levels of other biochemical markers in either group.

The intestinal microbiota, also called visceral brain, exhibits high biological activity and influences health status. The aim of this study was to evaluate selected dietary determinants of the levels of intestinal permeability markers (zonulin and LPS endotoxin) in a group of e-sportsmen. The study was conducted among 174 male athletes (18–28 years old), training at the professional (n = 44) and semi-professional level (n = 130). The study included: weight and height measurements (Holtain anthropometer, Tanita TBF300), assessment of BMI, determination of zonulin and LPS levels in fecal samples (ELISA tests) and assessment of frequency of consumption of selected food groups (FFQ). Statistical analysis was performed using chi2 and Student’s t tests and Spearman’s rank correlation, at a significance level of p < 0.05. The group was dominated by e-sportsmen with elevated levels of LPS endotoxin (66.67%), zonulin (85.74%) and normative BMI (59.70%), with no significant differences according to sports level. There was a positive correlation between BMI and levels of zonulin (R = 0.49; p < 0.001) and LPS (R = 0.24; p < 0.05). Zonulin levels also increased with more frequent consumption of sweet cereals (R = 0.21; p < 0.05), pork meats (R = 0.21; p < 0.05) and red meat dishes (R = 0.18; p < 0.05). Excessive body weight and a poor health diet were shown to have a negative effect on increasing intestinal permeability, suggesting the rationale for monitoring and rationalizing diet and nutritional status to optimize the intestinal microbiota of e-sportsmen.

Objective: The aim of the study was to determine the effect a mountain expedition (>3000 m) would have on the physical performance and nutritional indices of alpinists’ health status. Methods: The study included 17 men aged 30.29 ± 5.8 years participating in mountain expeditions to peaks of 5000–8000 m, lasting an average of 34 ± 6 days. The following were assessed: aerobic and anaerobic capacity, body composition and the values of selected biochemical and hematological indices of blood and urine before and after returning from the expeditions and a quantitative analysis of the alpinists’ diet. Results: There was a statistically significant decrease (p ≤ 0.05) in aerobic capacity, anaerobic capacity, subjects’ body mass, muscle mass and the lean body mass of the upper and lower extremities. There was a significant increase (p ≤ 0.05) in erythrocytes, hemoglobin, hematocrit, leukocytes, platelets, neutrophils, monocytes and a significant decrease (p ≤ 0.05) in total and high-density lipoprotein cholesterol, total bilirubin, albumin and total protein. A small percentage of the subjects met the requirements for iron (29.41%), folate (35.29%) and vitamin D (17.65%) supply with diet, as reflected in the blood test results. Conclusions: Despite the observed positive effect of three-week hypoxic exposure on the climbers’ health, the deterioration of aerobic and anaerobic capacity was shown, which, in addition to environmental conditions and systemic inflammation, may have been influenced by adverse changes in body composition. To improve the nutritional status of the body during the expedition and upon return, alpinists should consider including the necessary supplementation of deficient components.

Child and adolescent obesity represents a growing public health crisis, with profound implications for physical and mental well-being. Despite the well-established benefits of physical activity, over 80% of adolescents fail to meet the World Health Organization’s (WHO) recommendations for daily exercise. This manuscript explores gym-based strength training as a tailored intervention for obese youth who often struggle with aerobic activities. This paper critically examines medical eligibility, safety protocols, and injury risks while also detailing personalized training regimens that prioritize neuromuscular adaptation, functional strength, and long-term engagement. Additionally, it integrates evidence-based dietary strategies and supplementation practices appropriate for this age group, highlighting the role of the Mediterranean diet, DASH, and the cautious use of supplementation, particularly probiotics and protein, while discouraging performance-enhancing substances in youth. Emphasis is placed on interdisciplinary approaches, combining exercise, nutrition, and medical oversight to support holistic treatment. This study identifies gaps in the current literature and provides practical recommendations for designing safe, effective, and sustainable gym-based interventions for children with obesity, encouraging further research to validate these protocols in clinical settings. A comprehensive search was conducted across multiple databases, including PubMed/MEDLINE, the Cochrane Library, Science Direct, and EBSCO, focusing on English-language meta-analyses, systematic reviews, randomized clinical trials, and observational studies. The websites of prominent scientific organizations such as WHO, APP, and AIS were also reviewed. The selection of articles was a collaborative effort among all authors.