Does impedance measure a functional state of the body fat?

The aim was to compare methods of body fat measurement in different BMI groups. An additional aim was to discuss differences reflecting the structural and functional changes of fat tissue. The study group included 130 adult Caucasian women stratified by body mass index (BMI): 18-24.99 (n=30), 25-29.99 (n=26), 30-34.99 (n=33), 35-39.99 (n=30), and BMI>/=40 (n=11). Bioelectrical impedance was performed using Tanita TBF 410 GS, Bodystat 1500, and Omron BF 300. A caliper type Best was also applied. Correspondence of four methods with DEXA was assessed using the Bland-Altman and ANOVA analyses. Measurements by BIA were not significantly different from DEXA up to BMI of 30, but DEXA significantly overestimated in the higher BMI subgroup by all three methods. Caliper measurement significantly underestimated DEXA in all BMI subgroups. BIA methods overestimated DEXA for the obese subjects. Tanita did statistically the best. The Caliper test appeared less preferable than the BIA methods, especially in the higher BMI subgroup. DEXA and Caliper measurements seem to be the best estimate of structural (anatomical) fat quantity. We hypothesize that BIA methods could also measure some other physiopathological conditions like inflammation, hydration or cell infiltration of fat.

[Regular aerobic physical activity improves the lipid profile in persons with excessive body weight]. / Pravidelná aerobní pohybová aktivita zlepsuje lipidový profil u osob s vyssí nez normální telesnou hmotností.

UNLABELLED: A review of physical activity-induced lipid changes is presented. The review was compared with results we obtained in a reconditioning program involving 25 untrained obese patients who attended the reconditioning centre of the 1st Faculty of Medicine of Charles University for three months. A significant decrease was found in both HDL-cholesterol, triglycerides and the atherosclerosis index. No significant changes were recorded in the total and LDL-cholesterol level. CONCLUSION: Aerobic physical activity can induce changes in lipid levels in overweight and obese patients. Indication of regular aerobic physical activity should not be omitted in current practice.

[Effect of physical activity on serum leptin levels]. / Vliv fyzické aktivity na sérové koncentrace leptinu.

Leptin is a protein hormone produced predominantly by adipocytes. Its serum concentrations usually reflect the total body fat content i.e. they are higher in obese than in lean subjects. The aim of our study was to follow the influence of the regular hard physical training on the serum leptin levels. Therefore, the serum leptin levels in top rugby players, top race walkers and age and gender-matched control group were compared. The relationship between serum leptin concentrations and body mass index and body fat content was also studied. It was found that serum leptin levels in rugby players were significantly higher than in race walkers group, but lower than in control one. Serum leptin levels in race walkers were lower than those of rugby players and of control group. The body fat content in race walkers was lower than in resting two groups. There was no significant difference in body fat content between control and rugby players group. Serum leptin levels correlated positively with body mass index and body fat content both in control and in rugby players group. No statistically significant relationship was found between leptin and body mass index or body fat content respectively in race walkers group. We conclude that serum leptin levels in top sportsmen are lower than in non-sporting healthy age and gender-matched controls. The lower leptin levels in top sportsmen are probably in part the result of lower body fat content and in part the result of complex neurohormonal adaptation on the long term physical training.

The relationship of serum leptin levels and parameters of endurance training status in top sportsmen.

Leptin is a hormone that reflects the body fat content. It was reported that serum leptin levels were decreased in highly endurance-trained sportsmen in comparison with control non-sporting subjects. The aim of our work was to study the relation of serum leptin to blood viscosity and selected spiroergometric parameters of endurance capacity in a group of top rugby players and top race walkers. We have found that both body fat content and serum leptin levels were significantly lower in race walkers than in rugby players (9.68+/-3.65 vs 15.95+/-3.15% and 2.84+/-1.1 vs 3.89+/-1.09 ng x ml(-1) respectively, p<0.05). The positive correlation of serum leptin levels with body fat in both groups. The level of endurance training status was significantly higher in the race walkers group. Serum leptin levels significantly negatively correlated oxygen uptake per body and pulse oxygen per body weight only in rugby players but not in race walkers. Partial correlation test after adjusting for the effect of body fat content showed that leptin itself is not an independent predictor of endurance trainability in this group. Serum leptin levels correlated positively with blood viscosity only in race walkers, but not in the rugby players group. We conclude that serum leptin levels in top sportsmen parallel the changes in body fat content and are not an independent predictor of endurance training of these subjects.

[Effect of aerobic training in top athletes on serum leptin: comparison with healthy non-athletes]. / Vliv aerobního tréninku vrcholových sportovcu na sérové koncentrace leptinu: srovnání se zdravými nesportujícími subjekty.

Leptin is a protein hormone produced by adipocytes. Its serum concentration in the most of cases precisely reflect the total body fat content. The aim of our study was to follow up the influence of regular aerobic training on serum leptin levels. Therefore the serum leptin levels, basic anthropometric parameters and serum lipids were compared in 11 intensively trained race walkers and 10 age-matched non sporting control subjects. We have found, that serum levels, body weight, body mass index, body fat content, total and LDL-cholesterol were significantly decreased in walkers group in comparison with control subjects. Serum leptin levels positively correlated with body fat content and body mass index only in control group, in the walkers group the correlation was non-significant. The results of our study demonstrate, that regular aerobic training accompanied with the decrease of body fat content leads to the significant drop of serum leptin levels.

[Risk factors for ischemic heart disease in patients with chronic fatigue syndrome]. / Rizikové faktory ischemické choroby srdecní u pacientu s chronickým únavovým syndromem.

Risk factors of coronary artery disease (CAD) between a group of patients suffering of chronic fatigue syndrome (CFS) and a control group of healthy persons (whose exercise activity was not health-limited) were compared. Thirty three patients (27 women, 6 men, average age 39.9 +/- 11.7 years) and the same number of controls matched in age (39.8 +/- 10.3 years), gender and body weight. The Minnesota Questionnaire (by Taylor) and the Compendium of Physical Activities (by Ainsworth) were used to estimate total energetic expenditure in exercise activity as well as in job. The risk factors of CAD in the patients with CFS were not higher than in the control group. Aerobic physical fitness, basic anthropometric data, blood pressure, spectrum of blood lipoproteins, blood uric acid and smoking habits were not different between the compared groups. Patients suffering from CFS had lower total energetic expenditure in exercise activity. Nevertheless, this significant difference in sports activity was not large enough to cause any difference in risk factors of CAD between the CFS patients and the control group.

Lower serum leptin concentrations in rugby players in comparison with healthy non-sporting subjects--relationships to anthropometric and biochemical parameters.

Leptin is a protein hormone synthesized by adipocytes. Its serum concentrations reflect the total body fat content. Serum leptin concentrations are significantly higher in obese than in lean people and in women than in men. However little information about the influence of physical activity on serum leptin concentrations is available. We have compared the body weight, the body mass index (BMI), the body fat content (measured by caliper as skinfold thickness) and the serum concentrations of leptin, triglycerides, total, high density and low density lipoprotein (LDL) cholesterol in 14 top rugby players and 10 healthy controls. We found that serum leptin, total and LDL cholesterol concentrations were significantly lower in the rugby players group than in the control subjects. The body weight and BMI were significantly higher in the rugby players, while the body fat content was only slightly (non-significantly) higher in the control group. The serum leptin concentrations in both groups positively correlated with the BMI and body fat content and also with LDL concentrations in the control group. The serum leptin concentrations in the rugby players were lower than in the non-sporting subjects despite a similar body fat content in both groups. We would therefore suggest the possibility that regular hard physical training decreases serum leptin concentrations not only by the decrease of total body fat content, but also by a separate mechanism, which is not directly dependent on the changes in the amount of body adipose tissue.

[Trends in physical fitness in male white collar workers in the Czech population over the past 20 years]. / Vývoj fyzické zdatnosti dusevne pracujících muzu Ceské populace za posledních 20 let.

BACKGROUND: Common mortality and especially mortality on CAD is increased by low aerobic component of physical fitness. A study dealing with physical fitness changes of the Czech population has been still missing in our bibliography. The aim of the study was to evaluate physical fitness changes in the Czech male population since last 20 years. METHODS AND RESULTS: Physical fitness in 494 men in the age range of 20 - 60 years was compared to the men fitness examined 20 years ago. In the men of 20 - 29.9 years peak power (3.90 W vs 3.46 W, p < 0.01) and maximal ventilation (1.38 l.min-1 vs 1.24 l.min-1, p < 0.05) decreased. In the men 30 - 39.9 years old only peak aerobic power (37.2 ml.min-1 vs 35.7 ml.min-1, p < 0.05) slightly decreased. In the men 40 - 49.9 years old Vemax.kg-1 (1.38 l.min-1 vs 1.18 l.min-1, p < 0.001) and VO2max.kg-1 (35.6 ml.min-1 vs 32.4 ml.min-1, p < 0.001) severely decreased as well as in 50 - 59.9 years old men VEmax.kg-1 (1.23 l.min-1 vs 1.13 l.min-1, p < 0.05) and VO2max.kg-1 (32.7 ml.min-1 vs 29.4 ml.min-1, p < 0.001). CONCLUSIONS: Physical fitness of the Czech white-collar men decreased. The decline of physical fitness was related not only to lower exercise activity, but also to significant increment of body fat. Physical fitness, especially its aerobic component, decreased in Czech older men since last 20 years.

Physical fitness and CHD risk factors in operators and managers of nuclear and thermal power plants situated in environmentally different regions of the Czech Republic.

Nuclear and thermal power plants are seen as one of the threats to human health. Most investigations explore the potential hazards of radiation and the potential impact of a polluted environment. Less attention is being paid to the human factor, i.e. to the people who actually are directly involved in the generation of electrical power and whose sudden collapse could result in a disaster. In this paper dealing with the prevention of CHD we submit, in a condensed form, the results of our long-term testing of operators and managers from one nuclear and two thermal power plants, located in totally dissimilar regions of the Czech Republic. In our investigations, which are still going on, we are using a whole battery of methods--case history, anthropological, clinical and functional tests. Our test subjects are middle-aged men, an age group most prone to CHD. The most favourable results of the vast majority of tests were obtained at the nuclear power plant in southern Moravia, while the most adverse ones--with respect to the danger of CHD--in the men from the thermal power plant in Prague. For the most part these results, in the light of a thorough analysis of the case history, anthropological, clinical, functional and biochemical investigations of these middle-aged men, should be seen as the cumulative effect of both their way of life (locomotor activities, nutrition) and the environment, in which they live. The men working at the nuclear power plant live in the least polluted environment. People's way of life may to some extent be influenced and some preventive steps along these lines have already been taken.

Medical and anthropological study of a world and Olympic champion, long-distance runner, 35 years after the end his racing career.

E.Z. former world champion and holder of several gold and silver medals from Olympic Games as long-distance runner, underwent at the age of 71 comprehensive investigations. In 1993 following methods were used to establish E.Z. body build and health: Family, personal and sports history, anthropometry, somatotype, body composition posture values, sports medicine examination, ECG at rest, X-rays of the lung and heart, echocardiography at rest, systolic time intervals at rest, spirography at rest, hematology, biochemistry, X-rays of bones, exercise ECG changes and spiroergometry. Today, a typical feature of E.Z.'s bodybuild is a great amount of body fats, flabby musculature, faulty posture, restricted mobility of the spinal column and surprisingly good foot arches. The clinical findings are appropriate for his age, on his ECG at rest are signs of subendocardial ischemia above the left ventricle, atrial fibrillation and ventricular extrasystoles (Lown 1 a-b). Exercise ECG resulted in a deepening of the ischaemic changes already at a working load of 50 W. Hematology revealed normochromic macrocyt anaemia, biochemistry a borderline mineralogram, hyperuricaemia, higher S-GMT and HDL-C, T-C at the limit of normal values. X-rays of the bones were remarkable in two findings of that age. The pelvis, lumbar spine and knee joints were free of the usual pathological findings (osteoarthrosis), but presented with an exceptionally advanced osteoporosis.

[Is there a relation between cardiorespiratory fitness and systolic time intervals?]. / Existuje vzájemná souvislost mezi kardiorespiracní zdatností a systolickými casovými intervaly?

Systolic time intervals measured by polycardiography significantly correlated with some spiroergometric parameters of cardiorespiratory fitness both at rest and during dynamic exercise. The correlations were mostly free. There were considerable intraindividual differences. The method of polycardiography can thus not be recommended for exact intraindividual differentiation of left vetricular functional ability. Intraindividual detection of systolic time intervals will be the subject of our further investigation.