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Indexed/Abstracted in: Chemical Abstracts, CINAHL, Current Contents/Clinical Medicine, EMBASE, PubMed/MEDLINE, Science Citation Index Expanded (SciSearch), Scopus
Impact Factor 1,111
Online ISSN 1827-1928
Billat V. L. 1, Bocquet V. 1, Slawinski J. 1, Laffite L. 1, Demarle A. 1, Chassaing P. 1, Koralsztein J. P. 2
1 Laboratoire d’Étude de la Motricité Humaine, Université de Lille II, Faculté des Sciences du Sport, Ronchin, France;
2 Centre de Médecine du Sport CCAS, Paris, France
Background. The purpose of this study was to examine the influence of prior intermittent running at V.O2max on oxygen kinetics during a continuous severe intensity run and the time spent at V.O2max.
Methods. Eight long-distance runners performed three maximal tests on a synthetic track (400 m) whilst breathing through the COSMED K4 portable telemetric metabolic analyser: i) an incremental test which determined velocity at the lactate threshold (vLT), V.O2max and velocity associated with V.O2max (vV.O2max), ii) a continuous severe intensity run at vLT+50% (vΔ50) of the difference between vLT and vV.O2max (91.3±1.6% vV.O2max) preceded by a light continuous 20 minute run at 50% of vV.O2max (light warm-up), iii) the same continuous severe intensity run at vΔ50 with a prior interval training exercise (hard warm-up) of repeated hard running bouts performed at 100% of vV.O2max and light running at 50% of vV.O2max (of 30 seconds each) performed until exhaustion (on average 19±5 min with 19±5 interval repetitions). This hard warm-up speeded the V.O2 kinetics: the time constant was reduced by 45% (28±7 sec vs 51±37 sec) and the slow component of V.O2 (ΔV.O2 6-3 min) was deleted (-143±271 ml.min-1 vs 291±153 ml.min-1). In conclusion, despite a significantly lower total run time at vΔ50 (6 min 19±0 min 17 vs 8 min 20±1 min 45, p=0.02) after the intermittent warm-up at V.O2max, the time spent specifically at V.O2max in the severe continuous run at vΔ50 was not significantly different.