Relationship between blood lactate and excess CO2 in elite cyclists
|
 |
|
Post a Comment
|
|
|
|
|
CONTRIBUTORS:
|
|
|
JOURNAL:
|
|
|
YEAR:
|
1991
|
|
PUB TYPE:
|
Journal Article
|
|
SUBJECT(S):
|
CYCLING; ELITE-ATHLETE; BLOOD; LACTATE; CARBON-DIOXIDE; CORRELATION; ADAPTATION; BICYCLE-ERGOMETRY; SEX-FACTOR; MAN; WOMAN
|
|
DISCIPLINE:
|
No discipline assigned
|
|
HTTP:
|
|
|
LANGUAGE:
|
English
|
|
PUB ID:
|
103-366-296
(Last edited on
2002/03/07 18:25:56 US/Mountain)
|
|
SPONSOR(S):
|
|
|
ABSTRACT:
This study examined the relationship between expired non-metabolic CO2 (exCO2) and the accumulation of blood lactate. Particular emphasis was placed on the ventilatory (exCO2 and VE/VO2) and lactate threshold relationship. A total of 21 elite cyclists (15 males, 6 females) performed a progressive intensity bicycle ergometer test during which ventilatory parameters were monitored on-line at 15-s intervals, and blood lactate sampling occurred at each minute. Transition threshold values were determined for each of the three indices: excess CO2 (TexCO2), VE/VO2 (Tvent) and blood lactate (Tlac). The three threshold (TexCO2, Tvent, Tlac) all correlated significantly when each was expressed as an absolute VO2 (1 min-1). A significant ANOVA (F=8.41, P less than 0.001) and post-hoc correlated t-tests demonstrated significant differences between the TexCO2 and Tlac and the TexCO2 and Tvent values. The Tlac occured at an average blood lactate concentration of 3.35 mM, while the mean expired excess CO2 volume at the TexCO2 was 14.04 ml kg-1 min-1. Over an 11-min range across the threshold values (TexCO2 and Tlac), which were used as relative points of reference, the expired excess CO2 volume (ml kg=1min-1) and blood lactate concentration (mM) correlated significantly (r=0.69, P less than 0.001). Higher individual correlations over the same period of time (r=0.82-0.96, P less than 0.001) stress the individual nature of this relationship. These results indicate a strong relationship between the three threshold values. Changes in expired excess CO2 precede changes in blood lactate concentration and ventilatory equivalent (VE/VO2). Although changes in expired excess CO2 volume appear to track changes in blood lactate concentration, blood lactate concentration cannot be accurately predicted from expired excess CO2 volume as the nature of this relationship varies between individuals and appears to be influenced by gender.
|
|
|
|
STATISTICS
|
|
Click on # to view
|
|
Citations
|
|
0
|
|
References
|
|
0
|
|
Comments
|
|
0
|
|
Quality
|
|
0/0.00
|
|
Interest
|
|
0/0.00
|
|
View(er)s
|
|
4/506
|
|
|
|
|
|
|
| Prev |
Next |
|