[Influence of pulsating magnetic field used in magnet therapy and magnet stimulation on cortisol secretion in human].

The aim of our study was to test the influence of magnetic fields during magnetotherapy and magnetostimulation over a longer period of time (like in physiotherapy) on cortisol secretion in humans. The study population was divided into two groups: magnetotherapy group (16 men) and magnetostimulation group (10 men). Magnetotherapy in the form of magnetic field induction (2.9 microT; frequency--40 Hz; square wave; bipolar; Magnetronic MF--10 apparatus) was applied for 20 min to the lumbar area in patients with chronic low back pain. Magnetostimulation (Viofor JPS system; M2P2 program; induction--25-80 microT; frequency--200 Hz, complex saw-like shape with a plateau halfway the height of the wave; bipolar) was applied every day for 12 min in patients with the same health problem. In both groups, the procedures were repeated 15 times (about 10:00 a.m.) with weekend breaks. Serum samples were collected at 6:00, 12:00, 16:00 and 24:00 and estimated by the micromethod of chemiluminescence (DPC Poland; Cat. No. LKC01). The circadian profile of cortisol was determined prior to the application, a day and a month after application. The data were analyzed statistically, using paired and unpaired Student's test. Magnetotherapy affects the cortisol secretion in the circadian profile by decreasing its level at 16:00 a day after 15 applications, whereas magnetostimulation by increasing its level at 12:00 a month after 15 applications, which may suggest its long-term effect on hypothalamic-pituitary axis. The comparison of the results indicated that a day after magnetotherapy and magnetostimulation, the circadian curves of cortisol secretion differed significantly by about 100%. All hormone oscillations did not exceed the physiological norms of the circadian cortisol level, not reaching the level so high as in an intense stress. This suggests rather their controlling effect on the cortisol level than their significant stressogenic nature.