Seasonal Changes in 25(OH)D Concentration in Young Soccer Players-Implication for Bone Resorption Markers and Physical Performance.

Searching for potential relations between changes in 25(OH)D concentration and in physical fitness is an interesting scientific topic. Thus, the main purpose of this study was to investigate the changes in serum concentrations of 25(OH)D in young football players in conjunction with indicators determining bone resorption and physical fitness. A total of 35 young soccer players were tested during the autumn competition period. Biochemical analysis of blood, aerobic capacity, running speed and power tests (Wingate test, squat jump, counter movement jump) were carried out at the beginning and at the end of the competition period. Significant decrements in concentration of 25(OH)D from 33.9 ± 5.87 to 23.7 ± 5.58 ng/mL were noted after the analyzed competition period. There were no significant changes in aerobic capacity along the competition period. Significant improvements were observed in 10 m sprint, 30 m sprint (p < 0.001), maximal power (p = 0.011) and total work capacity (p = 0.024). We found that the effect of changes in the players' physical fitness does not occur in relation to 25 OH(D) concentration but occurs when these changes are analyzed as a function of the duration of the observation period. Changes in physical fitness of soccer players are determined by other factors then 25(OH)D concentration.

Assessment of the diet of male adolescents suffering from type 1 diabetes.

INTRODUCTION: Currently, 5-10% of diabetes patients are teenagers. During this period the influence of peers and observation of their eating habits plays a significant role. Unfortunately, they differ from the principles of proper nutrition, which according to the PTD Diabetes Poland should be introduced as an element of proper metabolic compensation. Aim of the study: To assess the condition and dietary habits of male adolescents with type 1 diabetes and to compare their eating habits to generally accepted standards. MATERIAL AND METHODS: The study participants include 20 boys, aged 14.6 ±1.58 years, with type 1 diabetes mellitus treated with a personal insulin pump who were diagnosed using ISPAD criteria. In the study anthropometric and questionnaire methods were used, as well as body composition analysis. RESULTS: In most of the examined subjects, the assessment of nutritional status indicates a proper proportion of adipose tissue (14.72 ±6.25%, 8.71 ±4.10 kg per kg) and muscle mass in the body (28.2 ±6.93 kg). Unfortunately in a significant group of adolescents, the diet is not properly balanced. Particularly the common problem is the excess of total carbohydrates, including simple sugars. CONCLUSIONS: To sum up, despite systematic education of proper nutrition on glycemic control and prevention of acute and chronic complications, the eating habits of male adolescents differ from those of proper nutrition. Additionally, it should be noted that despite the proper results of the body composition analysis, there is a problem with an erroneously balanced diet.

Responses to Low- and High-Intensity Exercise in Adolescents with Type 1 Diabetes in Relation to Their Level of VO2 Max.

The purpose of this study was to investigate the influence of maximal oxygen uptake (VO2 max) on the glycemic changes during low and high intensity exercises in young type 1 diabetic patients. Twenty boys (age: 14.3 ± 1.6 years; height: 171.0 ± 11.3 cm; weight; 59.5 ± 12.8 kg) were divided into low-fit group (LFG, n = 10) and high-fit group (HFG, n = 10). According to the experimental design, participants performed three physical efforts (VO2 max test, mixed aerobic-anaerobic effort and aerobic effort) on the cycloergometer, during which real-time glycemia was measured. Mixed aerobic-anaerobic exercise demanded significantly smaller carbohydrate supplementation (0.2 ± 0.2 g/kg during exercise) than the aerobic test session (0.4 ± 0.3 g/kg during exercise). Moreover, patients with higher VO2 max had lower tendency for glycemic changes during the aerobic effort. The results of the current study suggest that young type 1 diabetic patients should perform different intensity activities using continuous glycemic monitoring system to avoid acute and chronic complications of the disease.

Can athletes with type 1 diabetes use supplementation?

From year to year, we observe constantly growing revenue from the sale of supplements and functional food for athletes. The increased interest in their use raises many questions concerning the choice of products, portions, in addition in the case of athletes with type 1 diabetes - how they affect the level of glycaemia. In the group of people under 18 with diagnosed type 1 diabetes, the properly selected supplementation, which will not cause undesirable effects, is even more important. This publication aims to summarize the current reports on nutrients that come from: the present scientific knowledge, information on the labels, and information available on the websites of the most popular companies producing nutrients on the Polish market.

Acute Responses to Low and High Intensity Exercise in Type 1 Diabetic Adolescents in Relation to Their Level of Serum 25(OH)D.

The main purpose of this study was to investigate the differences in glycaemic reaction in response to various physical activities in 20 young boys (14.4 ± 1.6 years) with type 1 diabetes mellitus (T1DM) and with either vitamin D deficiency or with suboptimal levels of vitamin D. Participants were divided into two groups (deficiency group-DG, n = 10; suboptimal group-SG, n = 10) according to their vitamin D levels. All patients performed aerobic and mixed (aerobic-anaerobic) physical efforts. During the exercise, the respiratory responses and glucose levels were monitored. Biochemical blood analyses were performed before each physical effort. The oxygen consumption was not significantly lower in SG during both aerobic and mixed effort (4.0% and 5.6%, respectively). The glycated haemoglobin (HbA1c) level was higher by 6.1% and the total daily dose of insulin (DDI) was higher by 18.4% in the DG. The differences were not statistically significant. Patients with lower vitamin D levels demonstrated an insignificantly higher glycaemic variability during days with both aerobic and mixed exercises. An appropriate vitamin D concentration in T1DM patients' blood may constitute a prophylactic factor for hyperglycaemia during anaerobic training and hypoglycaemia during aerobic training.

Effect of eating resistant starch on the development of overweight, obesity,and disorders of carbohydrate metabolism in children.

Overweight and obesity in children is becoming an increasingly common problem due to the increased access to processed food, overly high energy density diet, and limitation of physical activity in children. Such trends in today's society lead to health consequences that can be observed in the early stages of carbohydrate metabolism disorders. Reduction of body weight and changes in eating habits can prevent the onset of type 2 diabetes. Recently, the benefits of consuming products containing resistant starch, which has the main advantage of influencing the metabolic pathway of glucose, have been increasingly underlined. To date, no recommendations have been made for the daily intake of resistant starch or its content in individual products available on the food market. However, in the medical literature, there are an increasing number of reported cases of the beneficial effect of consuming resistant starch as a factor that supports glycaemic control in children with carbohydrate disorders. Unfortunately, the above topic requires further research in this direction, especially in the developmental age population, which will allow the formulation of precise conclusions regarding its use in the prevention of overweight, obesity, carbohydrate metabolism disorders, and the development of diabetes.

Vitamin D Supplementation and Physical Activity of Young Soccer Players during High-Intensity Training.

The aim of this study was to confirm that vitamin D supplementation of young soccer players during eight-week high-intensity training would have a significant effect on their motion activity. The subjects were divided into two groups: the experimental one, which was supplemented with vitamin D (SG, n = 20), and the placebo group (PG, n = 16), which was not supplemented with vitamin D. All the players were subjected to the same soccer training, described as High-Intensity Interval Training (HIIT). The data of the vitamin D status, time motion parameters and heart rate were collected just before and after the intervention. A significant increase in 25(OH)D concentration (119%) was observed in the supplemented group, while the non-supplemented group showed a decrease of 8.4%. Based on the obtained results, it was found that physical activity indicators in the players were significantly improved during small-sided games at the last stage of the experiment. However, taking into account the effect of supplementation with vitamin D, there were no statistically significant differences between the placebo and the supplemented groups; thus, the effect size of the conducted experiment was trivial.