Warm-up effects on muscle oxygenation, metabolism and sprint cycling performance.
To investigate the effects of warm-up intensity on all-out sprint cycling performance, muscle oxygenation and metabolism, 8 trained male cyclists/triathletes undertook a 30-s sprint cycling test preceded by moderate, heavy or severe warm up and 10-min recovery. Muscle oxygenation was measured by near-infrared spectroscopy, with deoxyhaemoglobin ([HHb]) during the sprint analysed with monoexponential models with time delay. Aerobic, anaerobic-glycolytic and phosphocreatine energy provision to the sprint were estimated from oxygen uptake and lactate production. Immediately prior to the sprint, blood [lactate] was different for each warm up and higher than resting for the heavy and severe warm ups (mod. 0.94 ± 0.36, heavy 1.92 ± 0.64, severe 4.37 ± 0.93 mmol l(-1)                         P < 0.05), although muscle oxygenation was equally raised above rest. Mean power during the sprint was lower following severe compared to moderate warm up (mod. 672 ± 54, heavy 666 ± 56, severe 655 ± 59 W, P < 0.05). The [HHb] kinetics during the sprint were not different among conditions, although the time delay before [HHb] increased was shorter for severe versus moderate warm up (mod. 5.8 ± 0.6, heavy 5.6 ± 0.9, severe 5.2 ± 0.7 s, P < 0.05). The severe warm up was without effect on estimated aerobic metabolism, but increased estimated phosphocreatine hydrolysis, the latter unable to compensate for the reduction in estimated anaerobic-glycolytic metabolism. It appears that despite all warm ups equally increasing muscle oxygenation, and indicators of marginally faster oxygen utilisation at the start of exercise following a severe-intensity warm up, other energy sources may not be able to fully compensate for a reduced glycolytic rate in sprint exercise with potential detrimental effects on performance.
Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, UK. alwitt@essex.ac.uk
Anna
A
Wittekind
Chris E
CE
Cooper
Clare E
CE
Elwell
Terence S
TS
Leung
Ralph
R
Beneke
D000328:Adult; D000704:Analysis of Variance; D001642:Bicycling; D015415:Biomarkers / Q000097:blood; D004734:Energy Metabolism; D015444:Exercise; D005080:Exercise Test; D006019:Glycolysis; D006454:Hemoglobins; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D008954:Models, Biological; D018482:Muscle, Skeletal / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption; D010725:Phosphocreatine / Q000378:metabolism; D020127:Recovery of Function; D019265:Spectroscopy, Near-Infrared; D013647:Task Performance and Analysis; D013997:Time Factors; D055815:Young Adult
D015415:Biomarkers; D006454:Hemoglobins; D010725:Phosphocreatine; D019344:Lactic Acid; C100003:deoxyhemoglobin; D010100:Oxygen