Biomedical subjects

A Bringard

Publications and source records attributed to A Bringard.

4 recordsLinked to original sources

PubMed2006

Aerobic energy cost and sensation responses during submaximal running exercise--positive effects of wearing compression tights.

This study aimed to examine the effects of wearing compression compared to classic elastic tights and conventional shorts (control trial) on oxygen cost and sensation responses during submaximal running exercise. In part I, aerobic energy cost was evaluated in six trained runners at 10, 12, 14, and 16 km x h(-1). In part II, the increase in energy cost over time (i. e., slow component expressed as difference in VO2 values between min 2 and end-exercise) was determined in six trained runners at a constant running pace corresponding to 80% of maximal VO2 for 15 min duration. All tests were performed on a 200-m indoor track with equivalent thermal stress conditions. VO2 was determined with a portable metabolic system (Cosmed K4b2, Rome, Italy) during all testing sessions. Runners were asked their ratings of perceived exertion (RPE) and perceptions for clothing sweating, comfort, and whole thermal sensations following each trial. Results showed in part I a significant lower energy cost only at 12 km x h(-1) by wearing compression and elastic tights compared to conventional shorts. During part II, wearing compression tights decreased significantly VO2 slow component by 26 and 36% compared to elastic tights and conventional shorts, respectively. There were no differences in sweating and comfort sensations, RPE, and for whole thermal sensation between clothing conditions in parts I and II. Wearing compression tights during running exercise may enhance overall circulation and decrease muscle oscillation to promote a lower energy expenditure at a given prolonged submaximal speed.

Adult↗

PubMed2006

Effects of compression tights on calf muscle oxygenation and venous pooling during quiet resting in supine and standing positions.

AIM: We applied near-infrared spectroscopy (NIRS) to evaluate in resting conditions the effects of compression tights (CT) on calf muscle oxygenation and venous pooling compared with Lycra(R) elastic tights (ET) and shorts (no compression) according to the body posture (supine vs standing). METHODS: Twelve sportsmen regularly involved in endurance training volunteered to this study. Their average age, height and weight (+/-SD) were 26.5+/-2.6 years, 177+/-6 cm and 70.1+/-4 kg, respectively. Tissue oxygenation index (TOI), deoxyhemoglobin (HHb), and blood pooling (Hbtot) of the right gastrocnemius medialis were continuously monitored at 2 Hz using a NIRS device (NIRO-300, Hamamatsu Photonics, Japan). A home made transducer was used to measure applied pressure at the interface between skin and clothing over the calf area. Subjects were asked to realize a supine-standing protocol (5 min for each position) by wearing CT, ET or shorts in a counterbalanced order on the same day. RESULTS: HHb and Hbtot concentration changes were significantly lower whereas TOI was significantly higher by wearing CT compared with shorts and ET (P<0.001) as did supine compared to upright postures. The mean pressures applied over the calf were 5.6 and 23.2 mmHg during supine and 5 and 24.1 mmHg during standing for ET and CT, respectively. Pressures were significantly different among clothing according to the following rank order: CT>ET>shorts (P<0.001). CONCLUSIONS: CT compared to ET have positive effects on calf muscle oxygenation and venous pooling in quiet resting positions.

Adult↗

PubMed2003

Physiological and metabolic responses of triathletes to a simulated 30-min time-trial in cycling at self-selected intensity.

The aim of this study was to investigate the metabolic and physiological responses to a laboratory-based simulated 30-min individual time-trial (ITT 30 ) in cycling at a self-selected intensity. Twelve experienced triathletes (n = 4 women) performed a progressive incremental exercise test on a cycle ergometer to determine .VO2max (52 +/- 5 ml x min -1 x kg -1), maximum power output (300 +/- 12 W), and the second ventilatory threshold. Then, the subjects completed an ITT30 at self-selected work intensity on a stationary ergometer equipped with the SRM Training System. In all subjects, during the ITT30, heart rate and minute ventilation increased (p < 0.05) progressively whereas oxygen consumption and power output remained unchanged. Triathletes rode at consistent pacing corresponding to their highest steady state of blood lactate concentration that increased by no more than 1.0 mmol x l -1 during the final 20-min of ITT30. The self-selected intensity of triathletes during ITT30 represented 88 +/- 5 % (mean +/- SD) of .VO2max and was not significantly different to the energy demand corresponding to the second ventilatory threshold (84 +/- 5 % of .VO2max). Our data suggest that ITT 30 at a self-selected intensity is a good predictor of individual endurance capacity and may be used to estimate racing pace for training purposes. This performance test for the identification of the exercise intensity that demarcate "steady state" is less troublesome than some of the traditional methods, limiting testing to a single session.

Adult↗

PubMed1990

Multiphasic electrophoresis with diversified spacers.

The principle and some applications of multiphasic electrophoresis with diversified spacers are described. The method combines previously published concepts of introducing highly diversified spacers into the stack of an isotachophoretic system with the theory of snow- and telescope-electrophoresis. The link between this electrophoretic method and isotachophoresis on the one hand and monophasic zone electrophoresis on the other hand is exemplified. The importance of the nature of the spacers as well as of the pH and ions in the leading and terminating zone is illustrated. Details are given concerning the experimental set-up. This electrophoretic technique could serve as an alternative to isoelectric focusing.

Blood Proteins↗