Urinary mineral excretions were measured on five healthy 19-years-old female students in domestic sciences course of a woman's college and five healthy 18-19-years-old female students in physical training course, during the training camp of ski events.
The examination for the female students in domestic sciences course was done on 22 December as of ordinary time at school and on 23-25 December 1969 in training camp of ski event at a skiing ground. For the female students in physical training course the examination was done on 9-13 January 1970 in training camp at the same skiing ground and on 3-5 February 1970 in ordinary time at school. Every three hours urine was collected during the examination periods.
(1) Whole urine volume per 24 hours decreased in training camp in comparison with that in ordinary school time, while the excretion increased after the physical exercise and decreased during the sleeping hours.
(2) Creatinine excretion per 24 hours increased in the training camp and diurnally the excretion increased after the physical exercises. The variation of creatinine excretion seemed to be effected by the physical exercise.
(3) Decrease of Na excretion and increase of K excretion were observed in the students of domestic sciences course in training camp. Increase pattern of Na and K excretion with diurnal variation in training camp was observed with physical exercises.
(4) Urinary excretion of Ca and Mg increased by the female students of physical training course in training camp. On the diurnal pattern, the increase of Ca and Mg excretion caused by physical exercise showed some time lag of the peak compared to that of Na and K.
(5) Phosphorus excretion increased both in the students of domestic sciences course and of physical training course in training camp. The decrease of P excretion in the daytime and the increase in the sleeping hours was commonly observed for both groups.
(6) Following up the diurnal variations of urine volume and urinary excretions of Na, K, Ca and Mg in the female students of physical training course through the training camp for five days, difference between the increase of the excretions after, physical exercises and the decrease in sleeping hours got less day by day. Such a change seems to be the physiological adaptation of human body in order to control excess excretions of the important substances.
(7) Although the value of Na f K ratio fell in both student groups during training camp, the decrease was smaller for the physical training course group than for the domestic sciences course group. The fact that more excretions of urine volume and creatinine and less lowering of Na/K ratio than those of the domestic sciences course students were observed in the physical training course students seemed to be the effect of the daily training.