RESUMO
Fingertip and venous blood lactate concentrations were determined pre-exercise and after 4-min bouts of treadmill running at 2.69, 3.13, 3.58 and 4.03 m s-1 in 14 normal healthy volunteers. A 1-min rest period intervened each exercise period, and was used for the simultaneous sampling of fingertip and venous blood. Compared to pre-exercise, fingertip and venous blood lactate (BLa) concentrations increased significantly (P < 0.05) in a progressive pattern with increasing exercise intensity. Fingertip BLa concentrations were significantly higher (P < 0.05) than venous blood prior to exercise and in response to all four running speeds. Treadmill speed, heart rate and oxygen consumption were significantly lower (P < 0.05) at a BLa concentration of 4 mM when estimated from fingertip blood as compared with venous blood. These results indicate that differences between fingertip and venous blood exist during treadmill exercise and should be considered when lactate determination is employed as a criterion to evaluate and predict performance and when used as a training guide to standardize exercise intensity.
Assuntos
Lactatos/sangue , Corrida/fisiologia , Adulto , Coleta de Amostras Sanguíneas/métodos , Teste de Esforço , Feminino , Dedos/irrigação sanguínea , Frequência Cardíaca , Humanos , Masculino , Consumo de OxigênioRESUMO
The magnitude of induced color contrast was measured for tests whose areas, perimeter lengths, and shapes were independently varied. Test shapes were smoothly contoured, multiple-lobed figures generated from unitary Fourier shape descriptors. The shapes had from 3 to 40 lobes and were equal in area to a disk of diameter 2 deg, with perimeter lengths of 1.25, 1.75, 2.25, and 2.75 times the circumference of a 2-deg disk. The surround was a 5-deg disk. The surround was modulated sinusoidally along one of the three cardinal directions of color space around an equal-energy white of 50 cd/m2. The observer nulled the modulation induced into the test by adjusting the amplitude of real modulation in the test. The amplitude of nulling modulation was the measure of induction. The main result was that the amount of induction was similar for all tests of equal area irrespective of the shape or the length of perimeter.
Assuntos
Percepção de Cores/fisiologia , Sensibilidades de Contraste/fisiologia , Percepção de Forma , Análise de Fourier , Humanos , Luz , PsicofísicaRESUMO
The use of PERT as a standardized process for the placement of patients in community facilities is illustrated and advocated by the authors.
