14 research outputs found

    Characteristics of cardiorespiratory output determining factors among 11–19-year-old boys at rest and during maximal load: Its impact on systolic hypertension

    Get PDF
    As consequence of the expansion of sedentary lifestyle among schoolchildren the prevalence of particular symptoms related to decreased cardiorespiratory fitness increases. The purpose of this study was twofolds, on one hand to compare boys in three developmental groups: second childhood (G1), puberty (G2), young adult (G3) and on the other hand to compare groups classified on resting systolic blood pressure (RSBP) to differentiate cardiorespiratory output determining factors both at rest and at maximal load. Randomly selected apparently healthy boys were assessed, all subjects (n = 282) performed an incremental treadmill test until fatigue. Heart rate (HR), systolic and diastolic blood pressure (SBP and DBP), and oxygen consumption were measured. Resting HR was higher and resting SBP and DBP were lower in the G1 as compared to G2 and G3 (p < 0.05) but not differed at maximal loads. However indicators of cardiovascular load differed between groups. The oxygen pulse and Q were the lowest in the G1 and increased significantly between groups (p < 0.05). In conclusion based on our data we can suggest that there is an observable development of hypertension associated with maturation and cardiac output determining factors

    Physiological adaptations to specific endurance training in professional female handball players

    Get PDF
    Several Hungarian and foreign researchers have already studied the cardiorespiratory parameters of elite handball players. There are only a few studies though, which would separately review the changes in the functions of different organ systems. The aim of this study is to investigate the effect of an intervention (physical activity) on the cardiorespiratory system. In this study, 16 elite female handball players participated, whose body compositions were measured and took two vita maxima tests. During the analysis, each cardiorespiratory parameter was monitored for every 20 s. Between the two examinations, 6 weeks passed and an intervention took place. There was a significant decrease in relative body fat and a significant increase in relative muscle mass. Remarkable positive changes occurred in the values of ventilation, oxygen pulse, and in both absolute and relative aerobic capacities as well. The mean values of the team developed as expected, but the individual changes in body composition and cardiorespiratory parameters are just as important. First, we chose four players, who had the most outstanding changes. Second, we analyzed such parameters, which were expected to show adequate results in terms of the apparatus(es) functioning

    The Winchcombe meteorite, a unique and pristine witness from the outer solar system.

    Get PDF
    Direct links between carbonaceous chondrites and their parent bodies in the solar system are rare. The Winchcombe meteorite is the most accurately recorded carbonaceous chondrite fall. Its pre-atmospheric orbit and cosmic-ray exposure age confirm that it arrived on Earth shortly after ejection from a primitive asteroid. Recovered only hours after falling, the composition of the Winchcombe meteorite is largely unmodified by the terrestrial environment. It contains abundant hydrated silicates formed during fluid-rock reactions, and carbon- and nitrogen-bearing organic matter including soluble protein amino acids. The near-pristine hydrogen isotopic composition of the Winchcombe meteorite is comparable to the terrestrial hydrosphere, providing further evidence that volatile-rich carbonaceous asteroids played an important role in the origin of Earth's water

    Differences in cardiorespiratory responses of young and senior male endurance athletes to maximal graded exercise test

    Get PDF
    Within recent years the popularity of sportive activities amongst older people, particularly competitive activities within certain age groups has increased. The purpose of this study was to assess the differences in the cardiorespiratory output at anaerobic threshold and at maximal power, output during an incremental exercise, among senior and young athletes. Ten elderly male subjects [mean (SD) age: 68.45 ± 9.32 years] and eight young male subjects [mean (SD) age: 25.87 ± 5.87 years] performed an incremental exercise test on a treadmill ergometer. No significant differences in body size were evident; however, the differences between the groups for peak power (451.62 ± 49 vs. 172.4 ± 32.2 W), aerobic capacity (57.97 ± 7.5 vs. 40.36 ± 8.6 mL kg-1 min-1), maximal heart rate (190.87 ± 9.2 vs. 158.5 ± 9.1 beats min-1), peak blood lactate (11 ± 1.7 vs. 7.3 ± 1.4 mmol L-1), and % VO2max at ventilatory thresholds (93.18 ± 4.3 vs. 79.29 ± 9.9%) were significantly lower in the senior athletes. The power output at anaerobic threshold was also higher (392 ± 48 vs. 151 ± 23 W) in the young athletes, explaining the significant difference in terms of performance between these groups. We have observed an evident deterioration in some of the cardiovascular parameters; however, the submaximal exercise economy seems to be preserved with aging. Exercise economy (i.e. metabolic cost of sustained submaximal exercise) was not different considerably with age in endurance-trained adults
    corecore