[Power training for patients with arterial hypertension]. / Ist Krafttraining für Hochdruckpatienten gefährlich? Räumen Sie mit den alten Vorurteilen auf.

Nowadays, not only endurance training but also power training is recommended for patients with hypertension. In appropriately doses programs (no forced respiration), a number of studies have documented a blood pressure lowering effect. In the elderly hypertensive in particular, positive effects of power training that go beyond the simple lowering of elevated blood pressure may be expected.

Determinants of fat mass in prepubertal children.

The aim of the present study was to compare variables of metabolism, physical activity and fitness to body composition in normal and overweight children in a cross-sectional study design. Body composition was assessed by anthropometric measurements and bioelectrical impedance analysis in forty-eight prepubertal children (age 5-11 years, thirteen normal-weight, thirty-five overweight). Total energy expenditure (EE) was measured by combination of indirect calorimetry (for measurement of resting EE) and individually calibrated 24 h heart-rate (HR) monitoring. Activity-related EE and physical activity level (PAL) were calculated. Time spent with min-by-min HR>FLEX HR was also used as a marker of moderate habitual and vigorous activities. Aerobic fitness (O2 pulse (O2 consumption:HR at submaximal steady-state heart rate), submaximal O2 consumption (VO2submaximal), RER at a HR of 170 beats per min) was determined by bicycle ergometry. Muscle strength of the legs (maximal isometric strength of musculus quadriceps and of musculus ischiocruralis (Fa max and Fb max respectively)) was measured by computer tensiometry. When compared with normal children, overweight children had higher skinfold thicknesses (sum of skinfold thicknesses at four sites +160 %), fat mass (+142 %), waist (+24 %) and hip circumferences (+14 %), resting EE (+13 %) and RER (+5 %). No significant group differences were found for fat-free mass, muscle mass, total EE, activity-related EE, PAL, HR>FLEX HR, VO2submaximal, O2 pulse, Fa max and Fb max as well as the fat-free mass- or muscle mass-adjusted values for resting EE, aerobic fitness and muscle strength. When compared with normal children, overweight children had a lower measured v. estimated resting EE (Delta resting EE) and spent more time watching television. There were positive relationships between fat-free mass(x) and resting EE(x), total EE(y), aerobic fitness(y) and muscle strength(y), but only Delta resting EE(x) and HR>FLEX HR(x) correlated with fat mass(y). In a stepwise multivariate regression analysis resting EE adjusted for fat-free mass and Delta resting EE were significant determinants of % fat mass and explained 29.7 % of its variance. Thus, in the present cross-sectional study, resting EE was the most important determinant of fat mass.

Association between different attributes of physical activity and fat mass in untrained, endurance- and resistance-trained men.

The objective of this cross-sectional study was to assess different attributes of physical activity and fitness and their relationship to nutritional state in endurance- and resistance-trained, compared to untrained men. The subjects were 42 men matched for age, of which 13 were untrained [UT, mean age 30.2 years, mean height 180.7 cm, mean body mass 83.6 kg, mean body mass index (BMI) 25.6 kg.m-2], 14 were endurance-trained athletes (ET, mean age 29.6 years, mean height 178.4 cm, mean body mass 74.0 kg, mean BMI 23.2 kg.m-2) and 15 were resistance-trained athletes (RT, mean age 28.4 years, mean height 183.4 cm, mean body mass 94.1 kg, mean BMI 27.4 kg.m-2). Fat mass (FM), fat free mass (FFM), muscle mass (MM) and total body water (TBW) were assessed using anthropometry and bioelectrical impedance analysis. Resting energy expenditure was measured by indirect calorimetry (IC) and total energy expenditure (TEE) by a combination of IC and individually calibrated 24-h heart-rate monitoring. The activity related energy expenditure (AEE) and the physical activity level were calculated. Movements were assessed using pedometry. Aerobic fitness was determined using ergometry, muscle strength [quadriceps muscle (Famax), ischiocruralis muscle (Fbmax), biceps muscle (Fcmax), triceps muscle (Fdmax)] by computer tensiometry. Different time domain indexes of heart rate variability (HRV) were examined during sleep, rest and the whole day as an index of sympathetic nervous system (SNS) activity. When compared with UT and RT, ET had reduced body masses and FM, but increased percentage TBW (P < 0.05 and P < 0.01, respectively). FFM and MM were increased in RT, when compared with UT and ET (P < 0.01). ET had higher TEE, AEE, pedometry derived activities, oxygen consumption and power during vigorous exercise than RT and UT (P < 0.05 and P < 0.01, respectively). Respiratory exchange ratio at moderate exercise intensities was increased in RT (P < 0.05). In the 12 time domain indexes of HRV 6 and 10 were higher in ET than in RT and UT respectively (P < 0.05 or P < 0.01, respectively) suggesting an increased SNS activity in ET. By contrast, Famax, Fcmax and Fdmax were elevated in RT (P < 0.01). FM was negatively associated with aerobic fitness, but not with muscle strength. We concluded that the physiological and metabolic adaptations to exercise and nutritional state differ between ET and RT subjects. Participation in RT results predominantly in changes in body composition and strength but not in energy expenditure, movements and SNS activity. The opposite was the case for ET. Aerobic fitness, physical activity, movements and activity of SNS were all increased but body mass and FM were decreased. The latter finding may support the idea that, with regard to possible health benefits, ET is more effective than RT.

Is TV viewing an index of physical activity and fitness in overweight and normal weight children?

OBJECTIVE: To assess relationships between TV viewing and body composition, energy expenditure, physical activity, fitness and nutrition habits in prepubertal children. DESIGN: Cross-sectional study. SUBJECTS: Sixty prepubertal children (mean body mass index: 20.8 kg m(-2), age: 5-11 years, overweight: n = 52, normal weight: n = 8). METHODS: TV consumption, socio-economic status (SES) and nutrition habits were estimated by questionnaires. Fat mass and fat-free mass were assessed by anthropometrics and bioelectrical impedance analysis, and resting energy expenditure by indirect calorimetry. Total energy expenditure was measured by a combination of indirect calorimetry and individually calibrated 24-hour heart rate (HR) monitoring. Activity-related energy expenditure and physical activity level were calculated. Aerobic fitness (VO2 submax) was determined by ergometry, muscle strength (musculus quadriceps, musculus ischiocruralis) was measured by computer tensiometry. Children were stratified according to their daily TV consumption: 1 h of TV per day (group II). RESULTS: When compared with children of group I, children of group II had increased body weight, body mass index, skinfolds, fat mass and prevalence of overweight (P < 0.05 and <0.01, respectively). By contrast, fat-free mass, energy expenditure, measures of physical activity and muscle strength were similar. Children of group II had normal absolute VO2 submax but reduced adjusted VO2 submax (P < 0.05). They also had parents with a lower educational level (P < 0.05). Similar nutritional habits were observed in both groups. There were no significant differences in the observed parameters between children with high (1-3 h day(-1)) and very high (>3 h day(-1)) TV viewing. CONCLUSIONS: There is a positive relationship between TV viewing and fatness. Increased TV viewing does not reflect reduced 24-hour energy expenditure as assessed by 24-hour HR monitoring, submaximal VO2, muscle strength or poor dietary intake. Increased TV consumption is associated with a low SES.

Relationships between physical activity, physical fitness, muscle strength and nutritional state in 5- to 11-year-old children.

The purpose of the present study was to assess different aspects of physical activity and fitness in order to develop a basis for sport programmes for overweight and obese children. Eighty-eight prepubertal children (49 boys, 39 girls, 4.8-11.4 years old, 61% obese, 14% overweight and 25% normal weight) were examined. Body composition was assessed by combined use of anthropometrics and bioelectrical impedance analysis. Resting energy expenditure (REE) and total energy expenditure (TEE) were measured by indirect calorimetry (IC) and individually calibrated 24-h heart rate (HR) monitoring, respectively. Activity-related energy expenditure (AEE) and physical activity level (PAL) were calculated from TEE and REE. Fitness [assessed by O2-pulse, respiratory exchange ratio (RER) at submaximal work intensities] was determined by ergometry. The maximal isometric muscle strength of the legs (m. quadriceps, Fa max, m. ischiocruralis, Fb max) was measured by computer tensiometry. Children were grouped according to their nutritional state, AEE, O2-pulse and muscle strength. When compared with normal weight children, obese and overweight children had increased fat mass (FM), fat-free mass (FFM), waist-to-hip ratio and REE, but no group differences were observed for TEE, AEE, and PAL. Obese and overweight children spent more hours per day watching TV. After correction for body weight and FFM, no group differences in REE were observed, but normal weight children had a higher O2-pulse than overweight and obese children. By contrast, RER was increased in the latter group. The fittest group had the lowest body weight, BMI, FM and FFM. Children with a low O2-pulse spent more hours per day watching TV. Grouping children according to their degree of muscle strength, younger children (4-7.5 years) did not show group differences in nutritional state, energy expenditure, physical activity and fitness. However, in the group of 7.6- to 11-year-old children, those with the greatest muscle strength and FFM had reduced BMI, skin folds, FM and FFM. FM correlated inversely with O2-pulse, but was not associated with TEE, AEE, PAL or muscle strength. By contrast TV consumption was positively associated with FM. To summarize, overweight and obese children were less fit and watched more TV than their normal weight counterparts. FM did not correspond to TEE, AEE or PAL. Muscle strength was not associated with FM in young children, but was inversely associated with FM in older children. Our cross-sectional data are consistent with the idea that increased fitness and reduced physical inactivity may prevent children from being overweight.

No effect of gender on different components of daily energy expenditure in free living prepubertal children.

BACKGROUND: There are limited and controversial data on the influence of gender on metabolic rate in prepubertal children. OBJECTIVE: To assess the effect of gender on resting energy expenditure (REE), activity-related energy expenditure (AEE), total energy expenditure (TEE) and physical activity level (PAL) in free-living prepubertal children. DESIGN: Cross-sectional study. SUBJECTS: 40 prepubertal children (24 boys, 16 girls, 4-11 y old (mean age: 7.0 +/- 1.2 y), BMI 13.1-32.0 kg/m2). MEASUREMENTS: Energy expenditure was measured by the combination of indirect calorimetry and individually calibrated 24 h heart rate monitoring. Body composition was assessed by anthropometrics and bioelectrical impedance analysis. Socio-cultural and socio-economic factors, as well as activities of daily living, were estimated by questionnaire for the parents. Boys and girls were matched for fat-free mass (FFM, boys: 25.9 +/- 8.5 kg; and girls: 24.4 +/- 4.5 kg, n.s.) and fat mass (FM, boys: 11.6-5.9 kg; and girls: 10.8 +/- 3.3 kg, n.s.). RESULTS: We found no sex difference in REE, AEE and TEE. PAL was 1.4 +/- 0.3 for boys and 1.2 +/- 0.4 for girls. REE and TEE were significantly related to FFM (r=0.62, r=0.81, r=0.60). FFM was found to be the most significant determinant of REE (r2=0.70). REE accounted for the largest part of the variance in TEE (r2=0.46). Gender had no significant effect. CONCLUSIONS: There is no effect of gender on energy expenditure in prepubertal children.

[Injury profile in school sports. A sports medicine analysis in an annual report on schools]. / Verletzungsprofil im Schulsport. Eine sportmedizinische Analyse im Jahresüberblick an allgemeinbildenden Schulen.

A current injury profile was constructed on the data of the accident reports (n = 6366) in school sport coming in with the municipality accident insurance association for Schleswig-Holstein. The largest injury frequency occurred at the period from 9 o'clock until 10 o'clock. In this way, the "2nd hour" showed the highest injury risk referring to the lessons. In this case, a significant connection appeared between motivation and injury risk. The upper extremities were affected with a part of about 48% of all injuries most frequently. Within the injury kinds the distortion in 45% of the cases dominated. Cause of the injuries was the ball in 28% of the cases. The most injuries within the ball games resulted at the basketball (17%). By far most injuries of upper extremities occurred during a game phase. In about 80% the cases the injuries were on the fingers identified caused by the ball. The present results can help to analyze causes of accident and discuss measures for the prevention of sport injuries during the school sport.