Respiratory and Cardiocirculatory Responses of Acclimatization of High Altitude Natives (La Paz, 3500 m) to Tropical Lowland (Santa Cruz, 420 m)

1982 ◽  
pp. 21-27 ◽  
Author(s):  
M. Paz Zamora ◽  
J. Coudert ◽  
J. Ergueta Collao ◽  
E. Vargas ◽  
N. Gutierrez
Keyword(s):  
High Altitude ◽  
Santa Cruz ◽  
La Paz ◽  
Tropical Lowland ◽  
High Altitude Natives

scholarly journals Lactate and epinephrine during exercise in altitude natives

1996 ◽  
Vol 81 (6) ◽  
pp. 2488-2494 ◽  
Author(s):  
Bengt Kayser ◽  
Roland Favier ◽  
Guido Ferretti ◽  
Dominique Desplanches ◽  
Hilde Spielvogel ◽  
...  
Keyword(s):  
Oxidative Phosphorylation ◽  
High Altitude ◽  
Power Output ◽  
Chronic Hypoxia ◽  
La Paz ◽  
High Altitude Natives ◽  
Blood Lactate Accumulation ◽  
Acute Changes ◽  
The Right ◽  
Epinephrine Concentration

Kayser, Bengt, Roland Favier, Guido Ferretti, Dominique Desplanches, Hilde Spielvogel, Harry Koubi, Brigitte Sempore, and Hans Hoppeler. Lactate and epinephrine during exercise in altitude natives. J. Appl. Physiol. 81(6): 2488–2494, 1996.—We tested the hypothesis that the reported low blood lactate accumulation ([La]) during exercise in altitude-native humans is refractory to hypoxia-normoxia transitions by investigating whether acute changes in inspired O2 fraction ([Formula: see text]) affect the [La] vs. power output (W˙) relationship or, alternatively, as reported for lowlanders, whether changes in [La] vs. W˙ on changes in[Formula: see text] are related to changes in blood epinephrine concentration ([Epi]). Altitude natives [ n = 8, age 24 ± 1 (SE) yr, body mass 62 ± 3 kg, height 167 ± 2 cm] in La Paz, Bolivia (3,600 m) performed incremental exercise with two legs and one leg in chronic hypoxia and acute normoxia (AN). Submaximal one- and two-leg O2 uptake (V˙o 2) vs.W˙ relationships were not altered by[Formula: see text]. AN increased two-leg peak V˙o 2 by 10% and peakW˙ by 7%. AN paradoxically decreased one-leg peak V˙o 2 by 7%, whereas peak W˙ remained the same. The [La] vs. W˙ relationships were similar to those reported in unacclimatized lowlanders. There was a shift to the right on AN, and maximum [La] was reduced by 7 and 8% for one- and two-leg exercises, respectively. [Epi] and [La] were tightly related (mean r = 0.81) independently of[Formula: see text]. Thus normoxia attenuated the increment in both [La] and [Epi] as a function of W˙, whereas the correlation between [La] and [Epi] was unaffected. These data suggest loose linkage of glycolysis to oxidative phosphorylation under influence from [Epi]. In conclusion, high-altitude natives appear to be not fundamentally different from lowlanders with regard to the effect of acute changes in[Formula: see text] on [La] during exercise.

Maximal exercise performance in chronic hypoxia and acute normoxia in high-altitude natives

1995 ◽  
Vol 78 (5) ◽  
pp. 1868-1874 ◽  
Author(s):  
R. Favier ◽  
H. Spielvogel ◽  
D. Desplanches ◽  
G. Ferretti ◽  
B. Kayser ◽  
...  
Keyword(s):  
High Altitude ◽  
Chronic Hypoxia ◽  
Acute Hypoxia ◽  
Bicycle Ergometer ◽  
La Paz ◽  
Altitude Exposure ◽  
Exercise Ventilation ◽  
High Altitude Natives ◽  
The Difference ◽  
Arterial O2 Saturation

Maximal O2 uptake (VO2max) was determined on a bicycle ergometer in chronic hypoxia (CH) and during acute exposure to normoxia (AN) in 50 healthy young men who were born and had lived at 3,600 m altitude (La Paz, Bolivia). VO2max was significantly improved (approximately 8%) by AN. However, the difference in VO2max measured in CH and AN (delta VO2max) was lower than that reported in sea-level natives (SN) who exercised in chronic normoxia and acute hypoxia. It is shown that high-altitude natives (HN) and SN have a similar VO2max in normoxia, but highlanders can attain a greater VO2max when O2 availability is reduced by altitude exposure. In addition, in HN, the higher the subject's VO2max in hypoxia, the smaller his delta VO2max. These results contrast with the data obtained in 14 lowlanders acclimatized to high altitude who showed that their delta VO2max was positively related to their VO2max in hypoxia, as previously reported in SN who exercised in acute hypoxia (A. J. Young, A. Cymerman, and R. L. Burse. Eur. J. Appl. Physiol. Occup. Physiol. 54: 12–15, 1985). Furthermore, arterial O2 saturation of HN behaved differently from acclimatized lowland natives, inasmuch as it fell less during exercise both in CH and AN. HN with high aerobic capacity display a lower exercise ventilation and a reduced arterial saturation, which could explain their inability to improve VO2max with normoxia.(ABSTRACT TRUNCATED AT 250 WORDS)

Hering—BreüEr Reflexes in High-Altitude Infants

1995 ◽  
Vol 88 (3) ◽  
pp. 345-350 ◽  
Author(s):  
J. P. Mortola ◽  
T. Trippenbach ◽  
R. Rezzonico ◽  
J. T. Fisher ◽  
M. Diaz ◽  
...  
Keyword(s):  
High Altitude ◽  
Airway Pressure ◽  
Breathing Pattern ◽  
Pulmonary Ventilation ◽  
Newborn Infants ◽  
Respiratory Effort ◽  
Santa Cruz ◽  
Inspiratory Time ◽  
La Paz ◽  
Low Altitude

1. Pulmonary ventilation was found to be similar in high-altitude and low-altitude newborn infants, but the breathing pattern was deeper and slower at high altitude (Mortola, J. P., Frappell, P. B., Frappell, D. E., Villena-Cabrera, N., Villena-Cabrera, M., Peña, F., Am Rev Respir Dis 1992, 46: 1206–9). We questioned the contribution of vagal reflexes to these differences in breathing pattern. 2. Measurements were performed on high-altitude (La Paz, Bolivia, 3600–4050 m, inspired O2 pressure ∼92 mmHg, n = 34) and low-altitude infants (Santa Cruz, Bolivia, 400 m, Pio2 ∼141 mmHg, n = 26). The strength of the Hering—Breüer inspiratory inhibitory reflex was estimated from the inspiratory time during a respiratory effort against airways closed at end-expiration (TIoccl). The strength of the Hering—Breüer expiratory facilitatory reflex was estimated from the expiratory duration when airways were occluded during expiration (TEoccl). 3. TIoccl was significantly longer than the open-airways TI at both low and high altitude, but significantly more so (∼14%) at high altitude. TEoccl was longer than open-airways TE in both groups of infants, but significantly less so at high altitude, whether TEoccl was compared between occlusions of similar tidal volume (on average, TEoccl at high altitude was 79% of that at low altitude) or similar airway pressure (87%). 4. The results suggest that at high altitude the contribution of the phasic volume-dependent vagal input to the inspiratory off-switch threshold is higher, and that the tonic vagal expiratory facilitation is lower, than at low altitude, presumably because of hypoxia. The larger VT and longer TE of the HA infant cannot be explained by these differences in vagal pulmonary reflexes.

Improved blood buffering in high-altitude natives?

2002 ◽  
Vol 93 (6) ◽  
pp. 2214-2215 ◽  
Author(s):  
Dieter Böning
Keyword(s):  
High Altitude ◽  
High Altitude Natives

Body water metabolism in high altitude natives during and after a stay at sea level

1981 ◽  
Vol 25 (1) ◽  
pp. 47-52 ◽  
Author(s):  
S. C. Jain ◽  
Jaya Bardhan ◽  
Y. V. Swamy ◽  
A. Grover ◽  
H. S. Nayar
Keyword(s):  
High Altitude ◽  
Sea Level ◽  
Body Water ◽  
Water Metabolism ◽  
High Altitude Natives

scholarly journals Sleep-related hypoxaemia and excessive erythrocytosis in Andean high-altitude natives

2004 ◽  
Vol 23 (1) ◽  
pp. 41-46 ◽  
Author(s):  
L. Spicuzza ◽  
N. Casiraghi ◽  
A. Gamboa ◽  
C. Keyl ◽  
A. Schneider ◽  
...  
Keyword(s):  
High Altitude ◽  
High Altitude Natives

Coca chewing among high altitude natives: Work and muscular efficiencies of nonhabitual chewers

1995 ◽  
Vol 7 (5) ◽  
pp. 607-616 ◽  
Author(s):  
Tom Brutsaert ◽  
Mark Milotich ◽  
A. Roberto Frisancho ◽  
Hilde Spielvogel
Keyword(s):  
High Altitude ◽  
High Altitude Natives

Sleep of Andean high altitude natives

1992 ◽  
Vol 64 (2) ◽  
pp. 178-181 ◽  
Author(s):  
J. H. Coote ◽  
Barbara M. Stone ◽  
G. Tsang
Keyword(s):  
High Altitude ◽  
High Altitude Natives
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