We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Short-term modulation of the exercise ventilatory response in humans.
- Authors
Wood, H. E.; Klocko, M. N.; Ranasinghe, K. G.; Mitchell, G. S.; Babb, T. G.
- Abstract
We tested the hypothesis that increased external dead space (DS) elicits short-term modulation (STM) of the exercise ventilatory response (EVR) in humans. STM is an augmentation of the EVR occurring within a single exercise trial. Twelve young men were studied at rest and during cycle exercise at 3 levels (10, 30, 50W; not randomized) in Control conditions (no added DS) and with 3 levels of increased DS (200, 400, 600ml; randomized). EVR (defined as the slope of VE vs. VCO2) increased progressively with the addition of increasing DS volumes (p<0.01), e.g. at 10W, from 23.0±6.7 in Control to 38.1±12.7 with 600ml DS. Increasing exercise intensity diminished EVR (p<0.01), e.g. with 400ml DS, from 32.7±8.0 at 10W to 26.2±4.8 at 50W; and the size of this effect varied significantly by DS level (p<0.01). The change in PETCO2 (dPETCO2) from rest to exercise was diminished by increasing DS volume (p<0.01), e.g. at 30W, from 4.2±2.7 mmHg in Control to 2.2±2.4 mmHg with 400ml DS, confirming that the increase in EVR was not due to stimulation by increased PETCO2. We conclude that EVR was augmented by increased DS with no significant change in dPETCO2, and hence that STM was observed. This is the first study that we are aware of to specifically address STM in humans and provides evidence of the capacity for modulation and plasticity of the EVR in young men.
- Subjects
EXERCISE physiology; ANAEROBIC threshold; YOUNG men; PHYSICAL fitness for men; EXERCISE for men
- Publication
FASEB Journal, 2007, Vol 21, Issue 6, pA932
- ISSN
0892-6638
- Publication type
Article
- DOI
10.1096/fasebj.21.6.a932-d