Acute Hypoxemia Depresses the Cardiorespiratory Response During Phase I Constant Load Exercise and Unloaded Cycling

Zattara‐Hartmann, Marie Caroline; Jammes, Yves

doi:10.1076/apab.104.2.212.12885

Cited by 2 publications

(3 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The present observations that the influences of hypoxemia on exercise-induced V E changes depends on the expression of data are easily explained by previous results on the consequence of hypoxia on the ventilatory response to 0 W work load cycling (Zattara-Hartmann & Jammes, 1996). We showed already that acute hypoxemia markedly depressed the plateau V E increase during 0 W cycling, an effect interpreted as the consequences of reduced firing rate of muscle spindles under hypoxic condition (Lagier -Tessonnier et al,1993).…”

Section: Discussionsupporting

confidence: 80%

“…The overall reduction in V CO 2 at rest partly explain measurements of low PaCO 2 values under hypoxic conditions (Table 1). We already demonstrated that acute hypoxia markedly depressed V E and fR changes during 0 W cycling (Zattara-Hartmann & Jammes, 1996). Hypoxia enhanced the total gain (exponential coefficient) of V E changes during exercise which was 100 ± 6, 144 ± 6 (P < 0.01) and 141 ± 8 ml.min -2 (P < 0.01) when FIO 2 equals 0.21, 0.15 and 0.10, respectively.…”

Section: Resultsmentioning

confidence: 74%

“…As previously shown (Stenberg et al, 1966;Richalet, 1990;Desplanches et al, 1993) heart rate increase was always accentuated whatever the expression of data. This fact cannot be explained by the different expressions of data because acute hypoxia also depresses HR changes during 0 W cycling (Zattara-Hartmann & Jammes, 1996) . In addition, we found that facilitating effect of hypoxia on HR was not proportional to the fall in PaO 2 value.…”

Section: Discussionmentioning

confidence: 96%

See 2 more Smart Citations

Cardiorespiratory Response to Progressive Leg Exercise under Acute Normobaric Hypoxia

Zattara‐Hartmann¹,

Jammes²

1996

Archives of Physiology and Biochemistry

View full text Add to dashboard Cite

There is no clear evidence that the cardiorespiratory response to progressive maximal leg exercise was affected in proportion to the fall in PaO2 as measured from arterialized ear lobe blood. Subjects inhaling room air (rest PaO2 = 81 +/- 1 mmHg) or hypoxic gas mixtures, containing 15% or 10% O2 in N2 (rest PaO2 = 60 +/- 3 and 45 +/- 1 mmHg, respectively), performed leg exercise until exhaustion above the ventilatory threshold, determined from the changes in the ventilatory equivalent for oxygen (VO2VEAT). Acute hypoxemia potentiated the increase in minute ventilation (VE) in response to exercise, but this effect was only found when VE changes were expressed in percent of data collected during the 0 W work load cycling period preceding exercise. Hypoxemia always potentiated the heart rate (HR) response to exercise. These effects of hypoxemia on VE and HR were not proportional to the fall in PaO2. In addition, severe hypoxemia depressed the pressor vascular response to exercise. By contrast, VO2max and VO2VEAT decreased in proportion to hypoxemia and VO2VEAT was also negatively correlated with the peak lactate concentration. It was concluded that severe hypoxemia attenuated the cardiorespiratory response to exercise, whereas its consequences on the metabolic components of exercise (VO2max, VO2VEAT, lactic acid production) seem proportional to the reduced muscle oxygen supply.

show abstract

Section: Discussionsupporting

confidence: 80%

Section: Resultsmentioning

confidence: 74%

Section: Discussionmentioning

confidence: 96%

See 1 more Smart Citation

Cardiorespiratory Response to Progressive Leg Exercise under Acute Normobaric Hypoxia

Zattara‐Hartmann¹,

Jammes²

1996

Archives of Physiology and Biochemistry

View full text Add to dashboard Cite

show abstract

Cardiopulmonary Response to Exercise in COPD and Overweight Patients: Relationship between Unloaded Cycling and Maximal Oxygen Uptake Profiles

Bâ

Delliaux

Cissé

et al. 2015

BioMed Research International

View full text Add to dashboard Cite

Cardiopulmonary response to unloaded cycling may be related to higher workloads. This was assessed in male subjects: 18 healthy sedentary subjects (controls), 14 hypoxemic patients with chronic obstructive pulmonary disease (COPD), and 31 overweight individuals (twelve were hypoxemic). They underwent an incremental exercise up to the maximal oxygen uptake (VO2max), preceded by a 2 min unloaded cycling period. Oxygen uptake (VO2), heart rate (HR), minute ventilation (VE), and respiratory frequency (fR) were averaged every 10 s. At the end of unloaded cycling period, HR increase was significantly accentuated in COPD and hypoxemic overweight subjects (resp., +14 ± 2 and +13 ± 1.5 min−1, compared to +7.5 ± 1.5 min−1 in normoxemic overweight subjects and +8 ± 1.8 min−1 in controls). The fR increase was accentuated in all overweight subjects (hypoxemic: +4.5 ± 0.8; normoxemic: +3.9 ± 0.7 min−1) compared to controls (+2.5 ± 0.8 min−1) and COPDs (+2.0 ± 0.7 min−1). The plateau VE increase during unloaded cycling was positively correlated with VE values measured at the ventilatory threshold and VO2max. Measurement of ventilation during unloaded cycling may serve to predict the ventilatory performance of COPD patients and overweight subjects during an exercise rehabilitation program.

show abstract

Acute Hypoxemia Depresses the Cardiorespiratory Response During Phase I Constant Load Exercise and Unloaded Cycling

Cited by 2 publications

References 22 publications

Cardiorespiratory Response to Progressive Leg Exercise under Acute Normobaric Hypoxia

Cardiorespiratory Response to Progressive Leg Exercise under Acute Normobaric Hypoxia

Cardiopulmonary Response to Exercise in COPD and Overweight Patients: Relationship between Unloaded Cycling and Maximal Oxygen Uptake Profiles

Contact Info

Product

Resources

About