Search results for "physical exertion"
showing 10 items of 204 documents
Effects of Easy-to-Use Protein-Rich Energy Bar on Energy Balance, Physical Activity and Performance during 8 Days of Sustained Physical Exertion
2012
Background Previous military studies have shown an energy deficit during a strenuous field training course (TC). This study aimed to determine the effects of energy bar supplementation on energy balance, physical activity (PA), physical performance and well-being and to evaluate ad libitum fluid intake during wintertime 8-day strenuous TC. Methods Twenty-six men (age 20±1 yr.) were randomly divided into two groups: The control group (n = 12) had traditional field rations and the experimental (Ebar) group (n = 14) field rations plus energy bars of 4.1 MJ•day−1. Energy (EI) and water intake was recorded. Fat-free mass and water loss were measured with deuterium dilution and elimination, respe…
Segmental contribution to forces in vertical jump.
1978
Performance of a vertical jump was analyzed with respect to the contribution of the different body segments to the forces acting on the whole body center of gravity. Both cinematograph and force-platform techniques were employed. The data disclosed that the take-off velocity in vertical jumps was caused by the different components as follows: knee extension 56%, plantar flexion 22%, trunk extension 10%, arm swing 10%, and head swing 2%. However, the average take-off velocity of the total performance (3.03 m/s) was only 76% from the theoretical maximum calculated from the segmental analyses. Optimal timing of the segmental performances was calculated to increase this “efficiency” to 84%. Gre…
Criteria for the determination of maximal oxygen uptake in patients newly diagnosed with cancer : Baseline data from the randomized controlled trial …
2020
IntroductionMaximal oxygen uptake ([Formula: see text]) is a measure of cardiorespiratory fitness often used to monitor changes in fitness during and after treatment in cancer patients. There is, however, limited knowledge in how criteria verifying [Formula: see text] work for patients newly diagnosed with cancer. Therefore, the aim of this study was to describe the prevalence of fulfillment of typical criteria verifying [Formula: see text] and to investigate the associations between the criteria and the test leader's evaluation whether a test was performed "to exhaustion". An additional aim was to establish new cut-points within the associated criteria.MethodsFrom the Phys-Can randomized c…
Postural control and physiological responses to a simulated match in U-20 judo competitors
2018
The aim was to evaluate the effects of judo combat on the athletes’ postural control (PC) and physiological loading before, during and after a simulated match. Seventeen under-20 regional and national level athletes completed one modified 7-min match. At baseline, during the combat (3rd and 7th minutes) and 2-min post-match centre of pressure (CoP) parameters were assessed. Heart rate (HR), blood lactate (BLa) and rating of perceived exertion (RPE) and local RPE (LRPE) were collected. Significant increments were observed in CoP mean positioning and velocity at 3rd and 7th minutes, but the CoP deviation in both axes was unaffected. HR and BLa were elevated at 3rd and 7th minutes, and they re…
Physical activity when riding an electric assisted bicycle
2017
Background: The objectives of the present study were to compare time spent cycling, exercise intensity, and time spent in moderate- (MPA) and vigorous intensity physical activity (VPA) when cycling on an E-bike and a conventional bicycle on two “cycling-to-work” routes with differences in topography, defined as a hilly and a flat route. Methods: Eight adults (23–54 years, two women) cycled outdoors on a conventional bicycle and an E-bike, on a flat (8.2 km) and a hilly (7.1 km) route, resulting in 32 journeys. Duration, elevation, and oxygen consumption were recorded using a portable oxygen analyser with GPS. A maximal cardiorespiratory fitness test was performed on a cycle ergometer. Resti…
The psychophysiological influence of exertion and affect on sport-specific cognitive and physical performance
2022
Objectives: The purpose of the present study was to examine differences in cognitive and physical performance, affective states, perceived exertion, and physiological responses between trials with cognitive, physical, or combined cognitive and physical load. Design: Randomised cross-over trial. Methods: Highly trained competitive orienteers (n = 15 men; n = 10 women) completed three randomised trials comprised of: (1) sport-specific cognitive tests; (2) 35-minute cycling time trial; and (3) combined sport-specific cognitive tests and 35-minute cycling time trial. Measures taken during the trials recorded affective states, perceived exertion, heart rate, blood lactate, cycling watts, as well…
Essay: Does training adversely affect long-term health?
2005
A number of philosophers and physicians living in ancient Greece thought that sport could harm both mind and body. Hippocrates, for example, acknowledged the health benefits of physical activity, but also believed that intense athletic competition had a harmful effect on the heart and other organs, and lowered resistance to disease. That athletes do not have a shorter life expectancy than the general population, however, was not appreciated until the 19th century. In 1873, J E Morgan published the results of his study of 294 British oarsmen who participated in the Oxford versus Cambridge boat races between 1829 and 1869. His findings indicated that these sportsmen lived about 2 years longer…
Stability of pedalling mechanics during a prolonged cycling exercise performed at different cadences.
2005
The aim of this study was to analyse the effect of pedalling rate on the pattern of mechanical torque application and on neuromuscular fatigue during prolonged cycling exercise. Eleven well-trained individuals performed three 1-h pedalling sessions, at 50 rev.min-1, 110 rev.min-1 and a freely chosen cadence, at an intensity corresponding to 65% of their maximal aerobic power. The mechanical torque applied on the right pedal was recorded for 30 s every 5 min while pedalling. Contractile and neural properties of the quadriceps and hamstring muscles were analysed before and immediately after each of the three pedalling sessions. The post-exercise reduction in knee extensors maximal voluntary c…
Differences in gender and performance in off-road triathlon.
2010
The aims of this study were: (1) to examine performance trends and compare elite male and female athletes at the off-road triathlon (1.5-km swim, 30-km mountain biking, and 11-km trail running) world championships since its inception in 1996, and (2) to compare gender-related differences between off-road triathlon and conventional road-based triathlon. Linear regression analyses and ANOVA were used to examine performance trends and differences between the sexes. Elite male performance times stabilized over the 2005-2009 period, whereas elite female performance times continued to improve, especially for the run leg. Differences in performance times between the sexes were less marked in swimm…
Effect of bicycle ergometer test on intraocular pressure in elderly athletes and controls.
2009
To evaluate the effect of intensive physical exercise on intraocular pressure (IOP) in 66- to 85-year-old subjects IOP was measured before and after a maximal bicycle ergometer test. The non-glaucomatous subjects comprised 85 males and 36 female athletes and 16 male and 22 female controls of corresponding age drawn from a population register. IOP was measured using a non-contact tonometer. The results indicated a decrease (> or = 2 mmHg) in 34% of the subjects, no change in 57% and an increase in 9%. The decrease was more pronounced in subjects with higher pre-test values. In all four subjects with a pre-test value above 22 mmHg a reduction from 4 to 11 mmHg was observed. The change in IOP …