european college of sport science

PP-PH08 Physiology 8
Methods: Twelve highly motivated male Swedish national elite cross-country skiers completed a test battery consisting of: isokinetic knee
extensor peak torque tests at three different velocities; three different vertical jumps tests; two-part treadmill roller skiing test determining
lactate markers, maximal oxygen consumption (VO2max) and time to exhaustion; 60 and 360 s double poling tests determining mean
upper-body power (DP60Pmean) (DP360Pmean) and mean oxygen consumption (DP60VO2mean) (DP360VO2mean).
Performance data were collected from the Swedish National Championship (SNC) in cross-country skiing (13-17 March 2008): 15-km with
individual start in classical technique (SNC15); 30-km double pursuit with mass-start (SNC30); sprint prolog in free-style technique
(SNCsprint). In addition to ski races, overall seasonal ski ranking points were collected from FIS 3rd Cross-Country Points List 2007/2008
published before SNC for distance (FISdist) and sprint (FISsprint) races.
Correlations between test parameters and performance data were established using Pearson´s correlation analysis. Prediction models
were created using standard multiple linear regression analysis.
Results: Time to exhaustion during the incremental treadmill roller ski test is best correlated with both SNC15 (r = -0.86, p < 0.001) and
SNC30 (r = -0.81, p < 0.01). For SNC15 significant correlations were shown with VO2max both absolute and relative to body weight, lactate
markers, DP60Pmean and DP60VO2mean. Corresponding correlations for SNC30 were: lactate markers, DP60VO2mean and percentage
decrease in mean knee extension peak torque when comparing highest and lowest velocities. Highest correlation coefficient for
SNCsprint was found for DP60Pmean (r = -0.93, p < 0.05). Significant correlations for SNCsprint was also detected for DP360Pmean as
well as DP360VO2mean and jump height in squat jump.
Prediction models explain 68, 91, 68, 77 and 82% of the variance in performance for SNC15, SNC30, SNCsprint, FISdist and FISsprint,
respectively.
Discussion: Correlations found in this study have validated several commonly used physiological tests with real elite cross-country skiing
performances. Frequently investigated test parameters like VO2max and anaerobic thresholds are of great importance for success in
cross-country skiing. Many recent research studies have focused on upper-body capacity and we could confirm that high mean power
production in double poling is necessary to be successful as elite skier in both sprint and distance races.
INTERACTION BETWEEN OXIDATIVE STRESS AND ANTIOXIDANT MARKERS IN ELITE FEMALE PLAYERS FOLLOWING A
SOCCER GAME.
ANDERSSON, H., KARLSEN, A., BLOMHOFF, R., RAASTAD, T., KADI, F.
SCHOOL OF HEALTH AND MEDICAL SCIENCES
Introduction: Exhaustive exercise may produce an excessive amount of free radicals leading to oxidative stress. Under normal conditions,
the production of free radicals is in a fine-tuned equilibrium with the antioxidant defence system (Blomhoff, 2005). During a soccer game
the aerobic energy system is highly taxed and increased free radical production is expected. Thus, we aimed to investigate the interaction
between biomarkers of oxidative stress and antioxidants levels in elite female soccer players in response to a 90-min game.
Methods: Blood samples were taken from 16 field players (22±3 yrs, 167±5 cm, 64±2 kg, 54±3 ml•kg-1•min-1) before, immediately and
21 h after a 90-min game. Plasma oxidised glutathione (GSSG), the ratio of reduced to oxidised glutathione (GSH:GSSG) and lipid peroxidation
measured by D-Roms test were used as biomarkers of oxidative stress. Plasma endogenous (uric acid, total glutathione–TGSH)
and dietary antioxidants(α-tocopherol, ascorbic acid- AA, total carotenoids, and polyphenols) were analysed using liquid chromatography
and the Folin-Ciocalteu method. The food intake was standardised for all players during the study and secured an optimal intake of
macro nutrients.
Results: Immediately after the game GSSG significantly increased, GSH:GSSG decreased and D-Roms levels were unchanged. Uric acid,
TGSH, AA and α-tocopherol significantly increased immediately after the game whereas total polyphenols decreased and total carotenoids
remained unchanged. GSSG and GSH:GSSG ratio returned to baseline at 21 h whereas D-Roms levels remained unchanged. Uric
acid, TGSH and AA returned to baseline 21 hrs after the game. In contrast, total polyphenols remained significantly reduced whereas αtocopherol
remained elevated. Significant increases above baseline were observed in total carotenoids only at 21 h.
Conclusion
A soccer game in elite female soccer players induced a transient increase in GSSG and reduction in GSH:GSSG ratio accompanied by a
robust response of the antioxidant defence systems. The orchestrated endogenous and dietary antioxidant responses in well-trained
players helped to prevent the occurrence of lipid peroxidation after a soccer game. These results differ from that observed following
soccer games in males where increased lipid peroxidation occurred for several days following the game (Ascensao et al., 2008; Ispirlidis
et al., 2008). The differences may be related to the antioxidant functions of the female hormone estrogens. Furthermore, as polyphenols
are only found in the circulation and not stored in the tissue, we suggest that the reduction in polyphenols following the game may be
used as a marker of increased free radical production.
Referenses
Ascensao A, Rebelo AN, Oliviera E, Marques F, Pereira L, Magalhaes J. (2008). Clin Biochem, 41, 841-851.
Blomhoff, R. (2005). Curr Opin Lipidol, 16, 1, 47-54.
Ispirlidis I, Fatouros IG, Jamurtas AZ, Nikolaidis MG, Michailidis I, et al. (2008). Clin J Sport Med, 18, 423-431.
THE SHORTEST TIME TO REACH MAXIMAL OXYGEN UPTAKE WITHOUT PRIOR WARM UP IN PROFESSIONAL SOCCER
PLAYERS
GATTERER, H., FAULHABER, M., KLAUSNER, F., BURTSCHER, M.
UNIVERSITY INNSBRUCK
Introduction: In very heavy exercise, preceded by adequate warm-up, VO2max and HRmax can be attained within one minute (Astrand
et al., 2003). However, with a restricted warm up, VO2 during short exhaustive treadmill runs of ~2min duration (i.e. 800 m run) was
shown to plateau at different levels below VO2max depending on pacing strategies (Sandals et al., 2006). The question arises about the
shortest time to achieve VO2max with optimal pacing and without a preceding warm up.
Methods
Eight professional male soccer players, accustomed to sprint training, performed a progressive paced field test to exhaustion consisting
of two laps on a track (first lap 50%, half lap 70% of the self estimated maximal performance capacity followed by an all-out sprint to the
finish line) and an incremental treadmill test (work increments of 1 km/h per minute). Oxygen uptake, minute ventilation and heart rate
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ANNUAL CONGRESS OF THE EUROPEAN COLLEGE OF SPORT SCIENCE