RESUMO
OBJECTIVE: To observe the effects of electric stimulation on the circadian rhythm of plasma cortisone in soldiers. METHODS: Electric stimulation or phototherapy was respectively performed in the popliteal region (behind the knee) of the soldiers at different time points and radio immunal assay was utilized to examine the plasma cortisone concentration. RESULTS: The plasma cortisone concentration exhibited obvious circadian rhythmicity. At the 3 time points before the lowest core temperature occurred, treatments with electric stimulation or phototherapy resulted in delayed phase of circadian cortisone rhythm, while the same treatments given at the 3 time points after the lowest core temperature caused earlier arrival of the phase. No changes in the rhythm phase in response to treatments at other time points. CONCLUSION: Both of electric stimulation and phototherapy can adjust the phase of the cortisol circadian rhythmicity, and the phase curve displayed photic response to the treatments.
