european college of sport science

Thursday, June 25th, 2009
logical stimuli. To assess these stimuli and characterize subsequent adaptations, not only the character of exercise but also recovery
should be considered when developing new training strategies.
HIGH INTENSITY PHYSICAL ACTIVITY CORRELATES WITH IMPROVEMENT IN VASCULAR FUNCTION IN 9-11 YEAR OLDS.
HOPKINS, N., STRATTON, G., TINKEN, T.M., MCWHANNELL, N., RIDGERS, N., GRAVES, L.E.F.
LIVERPOOL JOHN MOORES UNIVERSITY
Background. The prevalence of obesity and physical inactivity in Western countries has increased in recent years. Both are modifiable risk
factors for cardiovascular disease. Endothelial dysfunction has its origins in childhood and plays a fundamental role in the development
of the atherosclerotic disease process. However little is known about the factors which modify endothelial function in children. The present
study therefore aimed to examine the relationships between change in artery health and its predictors in children.
Methods This was an observational cohort study. We studied 116 nine-eleven year old children (70 female, 46 male). Flow mediated
dilation (FMD), an index of vascular health, was assessed in the brachial artery and normalised for differences in its eliciting shear rate
stimulus (FMD/SRAUC). Body composition was assessed by dual energy X-ray absorptiometry (DXA) and peak VO2 determined on a
treadmill ergometer. Physical activity (PA) was assessed over 5 second epochs using uniaxial accelerometry across a 7 day period. All
measurements were taken at baseline and repeated 16 weeks later, in order to assess whether changes in the above variables impacted
upon FMD. Change scores were calculated, correlations performed and stepwise backwards linear regression used to identify
predictors of change in FMD.
Results No sex differences existed so data was pooled. Change in FMD/SRAUC was correlated with change in high intensity PA (r=0.3,
p=0.002), change in average counts per minute (r=0.25, p=0.009) and change daily steps (p=0.202, r=0.034). Regression analysis revealed
that change in high intensity PA was the only predictor of change FMD/SRAUC (r2=0.126, p=0.001).
Conclusions FMD was not significantly related to changes in body composition, cardiorespiratory fitness levels or low to moderate intensity
PA. The significant association between change in FMD and change in high intensity physical activity suggests that future interventions
should focus on encouraging this form of behaviour.
AEROBIC INTERVAL TRAINING VERSUS STRENGTH TRAINING AS A TREATMENT FOR THE METABOLIC SYNDROME
STENSVOLD, D., TJØNNA, A.E., SKAUG, E.A., WISLØFF, U., SLØRDAHL, S.A.
NORWEGIAN UNIVERSITY OF SCIENCE AND TECHNOLOGY
Background: Physical inactivity and overweight is strongly associated with an increased risk for developing metabolic syndrome. The
syndrome is characterized by a clustering of risk factors related to cardiovascular disease and mortality such as increased blood pressure,
impaired glycemic control, excess of abdominal fat and dyslipidemia. Regular physical activity followed by increased fitness can
improve the metabolic profile and reduce the risk of developing cardiovascular diseases, however the optimal training regime for reversing
metabolic syndrome and its associated cardiovascular abnormalities remain undefined.
Methods: Forty subjects were randomized (stratified by gender and age) to either aerobic interval training (AIT, n=11), strength training (ST,
n=10), combination of aerobic interval training and strength training (COM, n=9), or a control group (n=10). Training was performed 3
times per week for 12 weeks, and risk factors comprising the metabolic syndrome were measured before and after the intervention in all
four groups.
Results: AIT and COM significantly increased VO2peak (34.2 ± 9.8 to 38.6 ± 11.3 ml•kg-1•min-1 for AIT and 28.4 ± 6.3 to 31.5 ± 10.2
ml•kg-1•min-1 for COM). Maximal strength was significantly increased after COM (EMM 1.8 kg•lbm-0.67, 95% CI, 0.935-2.626) ST (EMM
3.1 kg•lbm-0.67, 95% CI, 2.456-3.765) as well as in the control group (EMM 0.7 kg•lbm-0.67, 95% CI, -0.08-1.431). AIT significantly reduced
triglyceride levels (from 2.27 ± 0.97 to 1.83 ± 0.76 mmol/l) systolic blood pressure (from 140 ± 14.6 134.2 ± 12 mmHg) and diastolic
blood pressure (from 89 ± 8.1 to 85 ± 5.5 mmHg). Only ST reduced waist circumference significantly (from 111.5 ± 10.8 to 110 ± 11 cm).
Endothelial function measured as flow mediated dilatation (FMD) was significantly improved in all three training groups (AIT 7.1 ± 2 to 8.8
± 2.8, COM 7.2 ± 2 to 9.1 ± 2.4 and ST 8.1 ± 3.1 to 11 ± 4.7). No change occurred in weight, fasting plasma glucose, high density lipoprotein
or insulin C-peptide in either group.
Conclusion: Although all three training regimes improved abnormalities associated with the metabolic syndrome, 12 weeks of AIT was
superior to both strength training and a combination of interval and strength training for improving risk factors related to the metabolic
syndrome. Three out of the six risk factors identifying the metabolic syndrome were significantly improved after 12 weeks of aerobic
interval training.
EFFECTS OF DIFFERENT WARM UP INTENSITIES ON LACTATE DISTRIBUTION IN DIFFERENT BLOOD COMPARTMENTS
AND POWER OUTPUT
WAHL, P., ZINNER, C., HAEGELE, M., BLOCH, W., MESTER, J.
GERMAN SPORT UNIVERSITY
Introduction: An improved lactate transport across the red blood cell membrane might be an advantage during high intensity exercise by
increasing the muscle-to-plasma [La] gradient and therefore allowing more lactate/H+ to leave the muscle. It is hypothised that the
bioavailability of MCT (Monocarboxylattransporter) may be altered by translocation from cytoplasm to the membrane of RBC when it is
needed. Therefore we investigated if lactate transport across RBC membrane can functionally be influenced after maximal exercise by
previous different warming up protocols (WU).
Methods: At three subsequent visits to the laboratory, subjects performed 30 s lasting maximal sprint tests on a cycle ergometer with
different prior warm up intensities: 1. without prior warming up (W), 2. extensive warm up (E): 12 min cycling at 60% of VO2 peak, 3. intensive
warm up (I): 12 min cycling at 60% of VO2 peak including three 10 s lasting peaks at 200% of VO2 peak. After warming up, subjects
stayed in a sedentary position for 5 min followed by the maximal sprint test. Blood samples were taken under resting conditions, after
warming up, before sprint exercise (pre M) and in minute intervals during recovery (0 min-15 min) to determine lactate concentrations in
whole blood, plasma and RBC.
Results: The initial increments (pre M-0’) in plasma & RBC [La] showed significant differences between W/E and I. The RBC/plasma [La]
ratio of the increments (pre M-0’) was significantly lower for I (0.23 ± 0.06) compared to W & E (W: 0.28 ± 0.04 & E: 0.27 ± 0.04). These
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