In order to examine the validity of Conconi's heart rate threshold (ATHR) during rowing
ergometry, in accordance with the new recommendations of Conconi, ten young rowers
(age 17.5 [SD 1.7] years; height 182.5 [SD 5.9] cm; body mass 77.0 [SD 10.6] kg) were
submitted - at random and within 48 - 72 h - to two progressive incremental exercise
tests on a rowing ergometer. In the first test, the heart rate threshold (ATHR) was
determined during a ramp-like incremental test. In a second test, the lactate method
(150 W + 50 W · 3 min-1) was used to determine the 4 mmol · l-1 threshold (AT4) and the individual anaerobic threshold (IAT). Subsequently, each
subject performed within 48 - 72 h after the second progressive incremental exercise
test a 30 min prolonged exercise test (PET) at the power output corresponding to ATHR
to demonstrate whether or not a steady state in blood lactate concentration ([La-]bSS) could be maintained. Friedmann's analysis of variance, Wilcoxon signed ranks test
and Spearman rank correlation coefficient (rs) were used as statistical tools. Significant lower values for power output (p < 0.01)
and heart rate (HR) (p < 0.01) were found at IAT as compared to AT4 and ATHR. No relationships
were found between ATHR on the one hand and AT4 and IAT on the other hand, neither
for power output (rs = 0.27 and - 0.09), nor for HR (rs = - 0.08 and - 0.08). Coefficients of correlation
between AT4 and IAT were respectively 0.68 (p < 0.05) for power output and 0.79 (p
< 0.01) for HR. During PET only four out of 10 rowers reached the target time of 30
min at ATHR power output and only one rower showed a lactate steady state. From our
results we can conclude that power output at ATHR is overestimated and cannot be used
for the prescription of endurance training in rowing. The ATHR does not reflect the
anaerobic threshold and is therefore not relevant for monitoring continuous endurance
training in rowing.
Key words
Conconi's heart rate threshold - validity - anaerobic threshold - prolonged exercise
test
