[Event-related potentials following exercise bouts of different intensity].
BACKGROUND
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.


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+/-3.24 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.
Barak
Otto
O
Zavod za fiziologiju, Medicinski fakultet, Novi Sad. ottompotom@yahoo.com
Ivetić
Vesna
V
Filipović
Danka
D
Naumović
Nada
N
Lukac
Damir
D
Drapsin
Miodrag
M
Karaba-Jakovljević
Dea
D
Popadić-Gaćesa
Jelena
J
Klasnja
Aleksandar
A
Grujić
Nikola
N
D000328:Adult; D003071:Cognition; D018913:Event-Related Potentials, P300; D015444:Exercise / Q000502:physiology*; D006801:Humans