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PubMed · 15470321

Cerebral cortex activity during supramaximal exhaustive exercise.

K Shibuya·J Tanaka·N Kuboyama·S Murai·T Ogaki
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Abstract

AIM: The purpose of this study was to examine the effect of fatigue resulting from supramaximal dynamic exercise on cerebral cortex activity. METHODS: Five healthy male subjects (age 24.6+/-0.4 years, body weight 62.9+/-1.1 kg, height 175.3+/-1.2 cm, and maximal O2 uptake per body mass 48.4+/-1.3 ml/kg/min) participated in this study. All subjects performed at 120% of maximal oxygen uptake (VO2peak) on a cycle ergometer until reaching a state of volitional fatigue. Cerebral oxygenation was measured by near-infrared spectroscopy (NIRS) throughout the supramaximal constant exhaustive exercise. RESULTS: The mean exercise duration of the subjects was 147.2+/-3.4 s. The peak value of blood lactate concentration within 3-10 min after the exercise test was 14.4+/-0.1 mmol/l. Cerebral oxygenation (8.8+/-1.8 micromol/l) was increased significantly during the first minutes of exercise compared with the pre-exercise value (p<0.05) and cerebral oxygenation decreased with the passage of time during exercise. Cerebral oxygenation at the end of exercise decreased significantly compared with the resting value (-29.9+/-3.4 micromol/l, p<0.05). CONCLUSION: These findings suggest that the exhaustive exercise induces the decrease of cerebral function and that the fatigue resulting from dynamic exercise decreases the cerebral cortex activity.

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AdultBicyclingCerebral CortexExerciseExercise TestExercise ToleranceFatigueHumansLactic AcidMaleOxygen ConsumptionSpectroscopy, Near-InfraredTime FactorsJournal Article

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K Shibuya, J Tanaka, N Kuboyama, S Murai, T Ogaki. 2004. Cerebral cortex activity during supramaximal exhaustive exercise.. https://pubmed.ncbi.nlm.nih.gov/15470321/

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