Acute volume expansion preserves orthostatic tolerance during whole‐body heat stress
نویسندگان
چکیده
منابع مشابه
Heat-stress-induced changes in central venous pressure do not explain interindividual differences in orthostatic tolerance during heat stress.
The extent to which heat stress compromises blood pressure control is variable among individuals, with some individuals becoming very intolerant to a hypotensive challenge, such as lower body negative pressure (LBNP) while heat stressed, while others are relatively tolerant. Heat stress itself reduces indexes of ventricular filling pressure, including central venous pressure, which may be refle...
متن کاملVariability in orthostatic tolerance during heat stress: cerebrovascular reactivity to arterial carbon dioxide.
INTRODUCTION A high degree of interindividual variability exists in the magnitude of heat stress (HS)-induced reductions in orthostatic tolerance relative to normothermia (NT). This variability may be associated with HS-mediated reductions in cerebral perfusion (indexed as middle cerebral artery blood velocity; MCAV(mean)) and altered cerebrovascular regulation. METHODS We tested the hypothes...
متن کاملHeat stress reduces cerebral blood velocity and markedly impairs orthostatic tolerance in humans.
Orthostatic tolerance is reduced in the heat-stressed human. This study tested the following hypotheses: 1) whole body heat stress reduces cerebral blood velocity (CBV) and increases cerebral vascular resistance (CVR); and 2) reductions in CBV and increases in CVR in response to an orthostatic challenge will be greater while subjects are heat stressed. Fifteen subjects were instrumented for mea...
متن کاملHyperhydration: tolerance and cardiovascular effects during uncompensable exercise-heat stress.
This study examined the efficacy of glycerol and water hyperhydration (1 h before exercise) on tolerance and cardiovascular strain during uncompensable exercise-heat stress. The approach was to determine whether 1-h preexercise hyperhydration (29.1 ml H2O/kg lean body mass with or without 1.2 g/kg lean body mass of glycerol) provided a physiological advantage over euhydration. Eight heat-acclim...
متن کاملAcute plasma volume expansion: effect on metabolism during submaximal exercise.
To examine the effect of acute plasma volume expansion (PVE) on substrate selection during exercise, seven untrained men cycled for 40 min at 72 +/- 2% peak oxygen uptake (VO(2 peak)) on two occasions. On one occasion, subjects had their plasma volume expanded by 12 +/- 2% via an intravenous infusion of the plasma substitute Haemaccel, whereas on the other occasion no such infusion took place. ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The FASEB Journal
سال: 2008
ISSN: 0892-6638,1530-6860
DOI: 10.1096/fasebj.22.1_supplement.737.3