Lactic acid removal rates during controlled and uncontrolled recovery exercise

After a standardized 6-min bicycle ergometer exercise (89% VO2max) lactic acid removal rates were compared during recovery at rest and exercies at 29.7, 45.3, 61.8, and 80.8% VO2max, and twice while the subjects (N = 7) regulated their own recovery exercise. Blood samples were taken after the standardized exercise and every 5 min during the 30-min recovery periods. During the controlled recovery periods lactic acid removal rates were dependent on the intensity of the recovery (Y‣ = 0.103 + 0.218chi - 0.464 X 10(-2)chi2 + 0.252 X 10(-4)chi3). Optimal removal was predicted to occur at 32% VO2max. Removal rates during the self-regulated recoveries were not different (P greater than 0.05), but these removal rates were faster than during recovery at rest and exercise at 61.8 and 80.8% VO2max (P less than 0.01). Removal rates during the self-regulated recovery and recovery at 29.7 and 45.3% VO2max were not different (P greater than 0.05). The subjects were therefore able to remove lactic acid effectively when selecting their own recovery exercise.

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Event-related potentials following exercise bouts of different intensity

Medicinski pregled ◽

10.2298/mpns0712531b ◽

2007 ◽

Vol 60 (11-12) ◽

pp. 531-535 ◽

Cited By ~ 1

Author(s):

Otto Barak ◽

Vesna Ivetic ◽

Danka Filipovic ◽

Nada Naumovic ◽

Damir Lukac ◽

...

Keyword(s):

Physical Activity ◽

Positive Impact ◽

Event Related Potentials ◽

Bicycle Ergometer ◽

Whole Body ◽

Functional Diagnostics ◽

Ergometer Exercise ◽

Related Potentials ◽

The Impact ◽

Bicycle Ergometer Exercise

Introduction. A number of articles on physical activity analyze the effects of acute bouts of physical exercise on the whole body. These experiments mainly include questionnaires and measurements of reaction time. The use of event-related potentials in laboratories for functional diagnostics is only of recent date. The aim of this experiment was to give insights into the impact of physical activity of different intensity on the amplitude and latency of P300 cognitive potentials. Material and methods. After recording cognitive event-related potentials in 17 young (21.6?1.07 yrs) healthy adults (at Fz and Cz), the participants underwent a controlled bicycle ergometer exercise. Each exercise lasted 10 minutes, with successive increase in the intensity to 60%, 75% and 90% of the maximum pulse rate and maintaining this level of intensity for six minutes. Immediately after each bout of exercise, event-related potentials were recorded. Results. The amplitude of the P300 wave, following exercise intensity at 75% of the maximum pulse (Pmax) (Fz 15.00?4.57; Cz 18.63?8.83 mV) was statistically higher (p<0.05) than the amplitude of the P300 at rest (Fz 11.21?4.15 mV; Cz 13.40?8.04 mV), at 60% (Fz 11.86?5.11 mV; Cz 14.54?8.06 mV) and at 90% of maximum pulse (Fz 13.26?4.73 mV; Cz 14.91?8.91 mV). There were no statistically significant differences (p>0.05) between amplitudes at 60% of Pmax and values obtained at rest and at 90% of Pmax. Also, no statistically significant differences were recorded (p>0.05) among the latencies of P300 recorded at rest (Fz 323.57?13.24 ms; Cz 323.57?13.24 ms) and at 60% of Pmax (Fz 321.14?22.38 ms; Cz 321.86?22.88 ms), at 75% of Pmax (Fz 321.50?16.67 ms; Cz 322.50?14.60 ms) and at 90% of Pmax (Fz 326.29?7.85 ms; Cz 325.43?7.63 ms). Discusssion and Conclusion. Physical activity has a positive impact on cognitive functions. At intermediate intensities, the amplitude of P300 increases, but at submaximal intensities it decreases to values obtained at rest. However, the latency of P300 did not show a statistically significant change after different intensities of exercise.

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