ventilatory threshold

ven·til·a·to·ry thresh·old

(ven'til-ă-tōr-ē thresh'ōld)
Point during exercise training at which pulmonary ventilation becomes disproportionately high with respect to oxygen consumption; believed to reflect onset of anaerobiosis and lactate accumulation.

metabolic and related thresholds

intensities of exercise (expressed as power output or as percentages of aerobic capacity, O2 max) at which specific metabolic and related changes are considered to take place. A plethora of thresholds has been proposed historically. These included many giving the same label to different criteria, or different labels to the same criterion; a number also embodied assumptions about bodily processes, at best unproven and sometimes now known to be false. The table lists six which appear unambiguous, the first five exactly as first described and the sixth slightly modified; however the two that are not related to observable phenomena (anaerobic and aerobic thresholds) are not recommended for further use. The [Lac]b (blood lactate concentration) values cited are representative approximations for a healthy but untrained young adult; they are used in some laboratories as working indices, but should not be taken as definitions of the term concerned. Other usages in the literature include: (1) OBLA as equivalent to LT or AT - confusions possible only if the reference to continuous rise is omitted from the OBLA definition; (2) the 4 mmol.L- criterion being designated as any one of 'anaerobic', 'aerobic' or 'aerobic/anaerobic' thresholds. See table overleaf .
References in periodicals archive ?
1991) Multicentre study of the determination of peak oxygen uptake and ventilatory threshold during bicycle exercise in chronic heart failure.
Moreover, it was also verified that the predominant activity above the ventilatory threshold contributed to a progressive increase of HRfrom round to round, thus also contributing to a great perception of fatigue in the last rounds.
This model suggests that when exercise intensity is above ventilatory threshold, physiological homeostasis is perturbed with an increase in ventilation, muscular contraction, and blood lactate concentration.
Although not competitive at the time of the physiological studies, he was still running three times per week for 30-40 min and cycling for transportation, mostly at intensities below the ventilatory threshold (VT).
max] has been substantially criticized [9, 14, 15] since it seems that the relative parameters alone, without considering the individual ventilatory threshold (IVT), are not sufficient and adequate to individualize exercise intensity [9].
42) A ballet class, for example, was reported to be from low to moderate aerobic intensities, similar to dancers' first ventilatory threshold (VT1) or between first and second ventilatory thresholds (VT2).
Iron supplementation maintains ventilatory threshold and improves energetic efficiency in iron-deficient non-anaemic athletes.
2]max and the second ventilatory threshold (VT2) were established in the test, which was performed on a motorized treadmill (Saturn 250/100R, h/p/Cosmos, Germany).
2011 Automatic detection of maximal oxygen uptake and ventilatory threshold.
University of New Hampshire associate professor of kinesiology Timothy Quinn and his former graduate student Benjamin Coons set out to learn just how good this test, gaining in popularity over the past decade, is, and how it compared to two other laboratory-tested measures of intensity, the lactate threshold and the ventilatory threshold.
Numerous publications over the last 15 years have used a <<two threshold>> model for interpreting lactate and ventilatory threshold tests, as well as demarcating intensity ranges.
A study by Ahmaidi et al (31) investigating the effects of interval training on ventilatory threshold and cardiorespiratory responses in elderly healthy individuals showed significant improvement of both maximal aerobic capacity and submaximal exercise tolerance, with a significant decrease in heart rate after a 3-month program.