D. Le Gallais et al., Metabolic and cardioventilatory responses during a graded exercise test before and 24 h after a triathlon, EUR J A PHY, 79(2), 1999, pp. 176-181
Citations number
27
Categorie Soggetti
Physiology
Journal title
EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY AND OCCUPATIONAL PHYSIOLOGY
Previous studies have reported respiratory, cardiac and muscle changes at r
est in triathletes 24 h after completion of the event. To examine the effec
ts of these changes on metabolic and cardioventilatory variables during exe
rcise, eight male triathletes of mean age 21.1 (SD 2.5) years (range 17-26
years) performed an incremental cycle exercise test (IET) before (pre) and
the day after (post) an official classic triathlon (1.5-km swimming, 40-km
cycling and 10-km running). The IET was performed using an electromagnetic
cycle ergometer. Ventilatory data were collected every minute using a breat
h-by-breath automated system and included minute ventilation (V) over dot(E
)), oxygen uptake ((V) over dot O-2), carbon dioxide production ((V) over d
otCO(2)), respiratory exchange ratio, ventilatory equivalent for oxygen ((V
) over dot(E)/(V) over dotO(2)) and for carbon dioxide (V) over dot(E)/(V)
over dotCO(2)), breathing frequency and tidal volume. Heart rate (HR) was m
onitored using an electrocardiogram. The oxygen pulse was calculated as (V)
over dotO(2)/HR. Arterialized blood was collected every 2 min throughout I
ET and the recovery period, and lactate concentration was measured using an
enzymatic method. Maximal oxygen uptake ((V) over dot O-2max) was determin
ed using conventional criteria. Ventilatory threshold (VT) was determined u
sing the V-slope method formulated earlier. Cardioventilatory variables wer
e studied during the test, at the point when the subject felt exhausted and
during recovery. Results indicated no significant differences (P > 0.05) i
n (V) over dotO(2max) 162.6 (SD 5.9) vs 64.6 (SD 4.8) ml . kg(-1) . min(-1)
], VT [2368 (SD 258) vs 2477 (SD 352) ml . min(-1)] and time courses of (V)
over dot O-2 between the pre- versus post-triathlon sessions. In contrast,
the time courses of HR and blood lactate concentration reached significant
ly higher values (P < 0.05) in the pri-triathlon session. We concluded that
these triathletes when tested 24 h after a classic triathlon displayed the
ir pre-event aerobic exercise capacity, bud did not recover pretriathlon ti
me courses in HR or blood lactate concentration.