european college of sport science

DOES EXERCISE IN HOT ENVIRONMENTAL CONDITION IMPAIR DETECTION OF ERYHROPOIETIN DOPING?
CAILLAUD, C., TROUT, G., HOWE, C., SIMAR, D., FATSEAS, G., KAZLAUSKAS, R.
THE UNIVERSITY OF SYDNEY
OP-PH17 Physiology 17
The abuse of recombinant erythropoietin to stimulate red blood cells synthesis and to improve physical performance is a major concern
and improving rHuEPO detection is a real challenge. The current detection method approved by the World Anti-Doping Agency (WADA) is
based on the analysis of erythropoietin (EPO) isoforms distribution in urine. A concern has recently been raised as whether strenuous
prolonged exercise performed in hot environmental conditions may or not alter native EPO synthesis, EPO excretion or urine isoform
distribution. This study was designed to test whether intense exhaustive exercise performed in hot condition will: change haematological
parameters; modify EPO isoforms distribution in urine; impair rHuEPO detection via increased excretion of basic isoforms and/or increased
protein concentration.
After an initial maximal exercise test, 6 highly trained cyclists (26.5 (5) yrs, VO2max:61.1 (4) ml/kg/min) performed 1 hour’s cycling at 70%
VO2max in the heat (35oC, 40% rh). The participants then started the acclimatisation period: during 6 consecutive days they did 60 min of
cycling exercise at 70% VO2max in hot condition. Blood and urine samples were collected pre and 1hr post exercise during the first and
the last exercise session. Haematocrit (Hct), Haemoglobine concentration ([Hb]), EPO were measured and ON-hes and OFF-hre models
were calculated. Urine was analysed for EPO isoforms according to current recommendations by wada and updated by wada technical
document TD2007EPO. Pre acclimatisation, exercise did not significantly changed [Hb], Hct or models scores ([Hb]: 149.7 (13.6) vs 150.8
(7.5) g/l; Hct: 0.459 (0.04) vs 0.461 (0.03); ON-hes: 171 (22) vs 173 (22); OFF-hre: 84.5 (9) vs 86.3 (4). Post acclimatisation all variables declined
post exercise ([Hb]: 148.2 (11.4) vs 141.2 (11.6) g/l; Hct: 0.452 (0.04) vs 0.426 (0.03); ON-hes: 171 (17) vs 163 (13); OFF-hre: 78.8 (5) vs 74.1
(9)). None subjects reached critical cut off levels for identification of EPO doping. Our haematological data support previous reports and
demonstrate that 6 days of intense exercise in hot condition do not significantly change variables used in the indirect detection of rHuEPO
doping. Some of the changes observed are opposite of those expected to be induced by rHuEPO abuse. Results from urine samples
were analysed using both the current peak ratio criteria (B2:E) and the older criteria consisting in the percentage of basic isoforms. We did
not find any sample approaching the criteria required for the identification of rHuEPO. The results do not support a hypothesis that acute
or chronic exercise in hot environment might impair rHuEPO detection through shifts in the distribution of EPO isoforms. In conclusion this
study shows that vigorous aerobic exercise performed in the heat for several consecutive days does not lead to false positive cases of
EPO doping.
10:15 - 11:45
Oral presentations
OP-PH17 Physiology 17
FREELY CHOSEN CADENCE AN GROSS EFFICIENCY DURING ERGOMETER AND FREE BICYCLING
LEIRDAL, S., ETTEMA, G.
HUMAN MOVEMENT SCIENCE, NORWEGIAN UNIVERSITY OF SCIENCE AND TECHNOLOGY.
Introduction: Freely chosen cadence (FCC) may be regarded a fixed parameter, robust for many conditions. The effect of work rate on FCC
is unclear: Some studies provide evidence for a modest increase, while others report FCC not to change with work rate. Many laboratory
studies are performed on a bicycle ergometer, using a fixed work rate that is independent of the cadence that is chosen. The mechanism
that links cadence and work rate differs from the mechanism that applies in free cycling, where both cadence and gears can be used for
attaining a certain work rate. The purpose of this study was to examine the effect of the type of regulation of work rate on the relationship
between this work rate and FCC and gross efficiency.
Methods: 18 male well trained cyclists participated in the study. One group, free cycled (FC) on their own competition bike mounted on an
electromagnetic roller, could use gearing and cadence to achieve each power output level, imitating outdoor cycling. The other group
(EC) performed the same protocol on an ergometer with a computer controlled electro-magnetic brake mechanism that generates a
constant work rate, independent of cadence. Subjects performed an increasing work rate protocol from 100W up to exhaustion, with a
50W increment every 2 minutes. Pedal rate, oxygen consumption, and heart rate were measured continuously.
Results: Statistical analysis showed a strong interaction between group and work rate on cadence (p