[Obesity--a risk factor]. / Obezita--rizikový faktor.

The nutritional status of a selected population--859 male members of the Fire Rescue Service from 12 districts in the Czech Republic--was assessed in 1997 and 1998. The study provides extensive information on selected anthropometrical and biochemical parameters, especially on those, which are generally used as risk indices for the origin and development of cardiovascular disease (CVD): body mass index (BMI), body fat percentage (b. fat), waist circumference (waist), serum concentrations of total cholesterol (Tchol), HDL- and LDL-cholesterol (HDL-chol, LDL-chol), triacylglyceroles (TAG) and the atherogenic index (AI). As far as lipid parameters were concerned, increased serum levels were estimated in 30.4% (TAG), 54% (Tchol) and 60.9% (LDL-chol) of volunteers. Decreased serum levels of HDL-chol were found in 38.2% of volunteers. An AI higher than 3.5 a.u. was calculated for 79.9% of all subjects in study while an AI higher than 5.0 a.u. was calculated for 45.3% of all subjects. An AI higher than 3.5 a.u. was found in 62% of males with normal weight, in 85% of overweight males and in 92% of obese males. The results of the study proved the considerable prevalence of the overweightness and obesity in the male population group that was followed: according to the calculated BMI, 49.5% of volunteers were estimated to be overweight and 16.3% to be obese. The study concept made it possible to reveal the relationships among the anthropometrical and biochemical parameters followed. The correlation matrix documents a statistically significant dependence among the BMI or waist values and the serum concentrations of Tchol, LDL-chol, TAG and AI. A significant negative correlation was found between the HDL-chol serum concentration and the BMI or waist values. The variance analysis results (the estimated lipid parameter values were divided into groups according to BMI and waist categories) document a statistically significant increase in serum Tchol, LDL-chol, TAG and AI in age categories over 35 years in comparison with the category of men under 25 years of age. For Tchol and LDL-chol a statistically significant increase had already been found in the 25-35 year age category. In comparison with the normal weight category, Tchol serum levels and AI values were statistically significantly higher in both the overweight and obese categories. Statistically significant increase was proven for the TAG and LDL-chol serum levels in both the overweight II. gr. and obese categories. A statistically significant decrease in comparison with the normal weight category was found in the HDL-chol serum levels of both the overweight and obesity categories. In the same way, an increase in Tchol and LDL-chol, TAG serum concentrations and AI values in higher and high risk CVD categories (according to the waist circumference value) was found in comparison with the low CVD risk category.

[Prevalence of obesity in selected subpopulations in the Czech Republic]. / Prevalence obezity ve vybrané subpopulaci v Ceské Republice.

The authors present the results of an epidemiological study focused on monitoring selected anthropometric parameters which characterize the nutrition state. 933 volunteers altogether, in age group 19-60 years, were tested in the study. Anthropometric parameters such as weight, height, skinfold thickness and abdomen circumference were measured. BMI and fat tissue percentage were calculated on the basis of gathered data. Overweight was detected in 67.5% of monitored men, obesity in 17.0% of them. Overweight was detected in 50.0% of women, obesity in 18.9% of them. Waist circumference exceeding 102 cm was measured in 41.2% of men and waist circumference exceeding 88 cm in 41.7% of monitored women. The unfavourable nutrition state correlates with a high occurrence of cardiovascular and metabolic diseases appearing within the Czech population.

[Changes in autonomic nervous system activity in obese individuals during weight reduction]. / Zmeny aktivity vegetativního nervového systému u obézních osob a pri redukci nadváhy.

The frequency analysis (fast Fourier transformation) of heart rate variability follow-up during modified orthostatic test is the non-invasive method used to the evaluation of vegetative nervous system (NS) activity. There are only few data about the changes of the parameters in the groups with civilization diseases or with the presence of the risk factors of coronary heart disease. In the groups of 82 volunteers (BMI 24.9 +/- 2.7 kg/m2) and 37 healthy obese people (BMI 36.1 +/- 4.9 kg/m2) we compare some of the vegetative NS parameters. In 16 volunteers we measured the vegetative NS activity changes during the weight reduction regimen (10 day's hospitalization, daily energy intake 3300 kJ, weight before 101.5 +/- 18.1 kg, after 97.5 +/- 17.1 kg, p < 0.0001). Acute reactions to the energy restriction were evaluated in 3 groups of 10 volunteers during 3 days of the energy intake 3200, 6600 and 13400 kJ. Obese persons show a slight decrease of both sympathetic and parasympathetic NS activity. In the supine position only few changes in the sympathetic/parasympathetic NS activity ration were observed. In the standing position in obese group drop of the most indexes and decrease of sympathetic/parasympathetic NS activity ratio were described. Significant correlations between sympathetic NS activity and lipid oxidation (r = 0.329, p < 0.01) as well as saccharide oxidation (r = -0.258, p < 0.05) were observed. During the weight reduction slight increase of the parasympathetic NS activity and higher one in the sympathetic NS activity were measured. The values after weight reduction regime are comparable with the control group of the lean persons. Different changes of the parameters were described in standing and in supine position. Acute reaction on the low-energy diet was observed in a few days. It shows a slight increase of the NS activity parameters. Relative increase mainly in the sympathetic nervous system activity doesn't depend on the degree of energy deficit only, but some subjective factors may play a role (age, psychological and psychosocial factors, agreeability of the diet, behavioral factors ...). In the group of obese persons non-specific changes of the vegetative NS activity were observed. They are modulated by some behavioral factors. The tendency to the higher parasympathetic NS activity confirms the MONA LISA theory of the origin of obesity. Important are the informations of the return of the indexes after overweight reduction.

[Non-invasive methods for evaluation of body composition during weight reduction]. / Vyuzití neinvazivních metod hodnocení telesného slození v prubehu redukce hmotnosti.

As a result of positive energetic balance of organism, there is a cumulation of an excessive energy in the adipose tissue. Adipose tissue repletion represents the main characteristic of obesity. The objective of our work was to perform the comparative study for the evaluation of selected noninvasive methods used for the determination of body composition. We analysed the results of 4 methods of the body composition measurement: bioelectrical impedance (BIA), physical anthropometry (ANTHR), Deurenberg's calculation (FORM) and dual energy X-ray absorptiometry (DEN). The most statistically significant correlation was proved between the results of BIA and results of DEN method (r = 0.9145), and results of BIA and FORM method (r = 0.9014).

Human nonspecific response to sound stimulation.

Basic physiological responses were studied in healthy adult men exposed to various types of sound stimulation (white noise, pure tones, infrasound). The reaction of the cardio-vascular system to noise turned out to be nonuniform. Changes were observed in the patterns of standard electrocardiograms as well as spatial ballistocardiograms and dynamocardiograms. The magnitude of heart rate responses in the initial stage of stimulation showed a clearcut dependence on the level of noise load. In the first phase of adaptation distinct examinee-to-examinee variations were observed in the time to heart rate normalization, depending on the pattern of personality characteristics. Similar variations were also manifested in biochemical responses as well as in the patterns of EEG.