Consistent with previous findings,33e36 our study shows the
differences of the levels of 17b-estradiol and progesterone in
each group are correlated with the ultrastructural changes of
the ovarian cells observed under an electron microscope. It is
reasonable to hypothesize that the reduction of estradiol and
progesterone levels in serum is directly related to the impairment
of ovarian subcellular organelles, such as mitochondria,
endoplasmic reticulum, and Golgi complex where endogenous
estradiol and progesterone were synthesized.37,38 Human
studies indicates that athletes should follow diet and exercise
regimens that provide energy of 30e45 kcal/kg/day fat free
mass while training involving body weight control.21