Search results for "1200"

THE COMPETITIVE DEMANDS OF ELITE MALE RINK HOCKEY

2013

The aim of this study was to simulate the activity pattern of rink hockey by designing a specific skate test (ST) to study the energy expenditure and metabolic responses to this intermittent high-intensity exercise and extrapolate the results from the test to competition. Six rink hockey players performed, in three phases, the 20-metre multi-stage shuttle roller skate test, a tournament match and the ST. Heart rate was monitored in all three phases. Blood lactate, oxygen consumption, ventilation and respiratory exchange ratio were also recorded during the ST. Peak HR was 190.7±7.2 beats · min(-1). There were no differences in peak HR between the three tests. Mean HR was similar between the …

Effects of the exercise in the cerebral blood flow and metabolism: A review

2015

In recent years it has been shown that cerebral blood flow is affected by intense exercise, what may even lead to a reduction in the cognitive capacity. This statement is contrary to the traditional belief that cerebral blood flood remains constant and unaltered even when exercise is performed. During physical exercise of moderate intensity, cerebral blood flow increases in the cerebral areas responsible for movement. Moreover, recent studies have observed that cerebral blood flow decreases during high-intensity exercise as a consequence of a local hyperventilation and vasoconstriction of the areas with lower cerebral activity. Traditionally, the glucose has been considered as the main and …

A standard calculation methodology for human doubly labeled water studies.

2021

Summary The doubly labeled water (DLW) method measures total energy expenditure (TEE) in free-living subjects. Several equations are used to convert isotopic data into TEE. Using the International Atomic Energy Agency (IAEA) DLW database (5,756 measurements of adults and children), we show considerable variability is introduced by different equations. The estimated rCO2 is sensitive to the dilution space ratio (DSR) of the two isotopes. Based on performance in validation studies, we propose a new equation based on a new estimate of the mean DSR. The DSR is lower at low body masses (<10 kg). Using data for 1,021 babies and infants, we show that the DSR varies non-linearly with body mass betw…

Representation of physical activity domains and sedentary behaviors across categories of gender and disability in children’s TV cartoons

2018

Television (TV) cartoons could reflect and shape social values about children’s health-related behaviors. The main aim of this study is to analyze the portrayal of physical activity (PA) domains in the most popular Spanish children’s television (TV) cartoons. It is performed a content analysis of each scene following a coding scheme. The sample selected included the five most popular children’s TV cartoons for the 2013-2014 period in Spain. Our results show a large gap between the modest representation of different PA domains compared to the overwhelming depiction of sedentary behaviors. We do not find evidence of males and females participating equally in a variety of PA domains, and we fa…

Les ducs Valois et les villes du duché de Bourgogne

1993

In vivo localized gastrocnemius subtendon representation within the healthy and ruptured human Achilles tendon

2022

The Achilles tendon (AT) is composed of three distinct in-series elastic subtendons, arising from different muscles in the triceps surae. Independent activation of any of these muscles is thought to induce sliding between the adjacent AT subtendons. We aimed to investigate displacement patterns during voluntary contraction (VOL) and selective transcutaneous stimulation of medial (MGstim) and lateral (LGstim) gastrocnemius between ruptured and healthy tendons, and to examine the representative areas of AT subtendons. Twenty-eight patients with unilateral AT rupture performed bilateral VOL at 30% of the maximal isometric un-injured plantarflexion torque. AT displacement was analysed from sagi…

The relationship between the incidence of winners/errors and the time spent in different areas of the court in elite tennis

2013

Martinez-Gallego R, Guzman JF, James N, Ramon-Llin J, Crespo M, Vuckovic G. The relationship between the incidence of winners/errors and the time spent in different areas of the court in elite tennis. J. Hum. Sport Exerc. Vol. 8, No. Proc3, pp. S601-S607, 2013. Winners and errors have been two of the most studied performance indicators in tennis, contributing to the prediction of match outcome and definition of the playing style of the players. Furthermore, the position occupied by the player on the court has also been shown to be a good indicator of both the final result and style of play. The aim of this study was to examine whether there were differences between game winners and losers i…

Sport burnout inventory–Dual career form for student-athletes: Assessing validity and reliability in a Finnish sample of adolescent athletes

2020

Background: The pressure of pursuing an athletic career simultaneously with education may set adolescent student-athletes at risk for sport and school burnout. Although the 2 life domains of student-athletes are strongly intertwined, so far, there has not been an instrument for investigating sport burnout parallel to school burnout. The aim of the present study was to introduce a sport burnout measure for adolescents in a dual career context and investigate its validity and reliability by using confirmatory factor analysis. Methods: The participants were 391 student-athletes (51% females) who filled in a questionnaire of sport burnout and background variables in the beginning of upper secon…

Daily energy expenditure through the human life course

2021

Total daily energy expenditure (“total expenditure”, MJ/d) reflects daily energy needs and is a critical variable in human health and physiology, yet it is unclear how daily expenditure changes over the life course. Here, we analyze a large, globally diverse database of total expenditure measured by the doubly labeled water method for males and females aged 8 days to 95 yr. We show that total expenditure is strongly related to fat free mass in a power-law manner and identify four distinct metabolic life stages. Fat free mass-adjusted daily expenditure accelerates rapidly in neonates (0-1yr) to ~46% above adult values at ~1 yr, declines slowly throughout childhood and adolescence (1-20 yr) t…

Effects of caffeine on neuromuscular function in a non‐fatigued state and during fatiguing exercise

2020

New findings What is the central question of the study? What are the effects of caffeine on neuromuscular function in a non-fatigued state and during fatiguing exercise? What is the main finding and its importance? In a non-fatigued state, caffeine decreased the duration of the silent period evoked by transcranial magnetic stimulation. Caffeine-induced reduction of inhibitory mechanisms in the central nervous system before exercise was associated with an increased performance. Individuals who benefit from caffeine ingestion may experience lower perception of effort during exercise and an accelerated recovery of M-wave amplitude postfatigue. This study elucidates the mechanisms of action of …