the hormones dominating the phases are gonadotropin releasing hormone ( gnrh ) , 
 follicle - stimulating hormone ( fsh ) , luteinizing hormone ( lh ) , estrogen and progesterone . 

these hormones can be changed by exercise estrogen and progesterone increase after acute 
 exercise . in the menstrual period ,
progesterone and estrogen secretion is suppressed by chronic 
 exercise1 , 8 , 
 13 , 26 .
the performance of female athletes during their menstrual periods 
 has attracted the attention of researchers for many years .
, studies have not detected any decrease in the performance of female 
 athletes during their menstrual periods4 , 6 , 10 , 24 . in this study ,
the effect of maximal 
 aerobic exercise the luteal phase on some gonadal hormones and alpha - fetoprotein ( afp ) in 
 female athletes was researched .
it has a molecular weight of 70 kd is and 
 it synthesized by the yolk sac , fetal gastrointestinal tract , and liver20 .
it is an important parameter in pregnancy follow - up as the afp level increases in 
 intrauterine fetal deaths , hydrocephalus , hemolytic diseases , placental separations , and 
 neural - tube defects in pregnant women21 . 

the measurement of afp level is important for tracing prognosis and diagnosis hepatoma and 
 germ cell tumors18 , 21 .
serum afp is also elevated in 524% of malignancies of the 
 pancreas , stomach , and colon20 . in a 
 12-week study performed in 2014 , ko et al .
found no change in the afp level of women aged 
 around seventy after 1 , 3 and 5 days of an exercise program .
our study will contribute to 
 the literature in terms of the relationship between afp and exercise .
estrogen is an 18-carbon corticosteroid molecule released from the ovaries of women and 
 from the testis of men .
furthermore , it is also affects the cardiovascular system , muscle skeletal 
 system , immune system , and central nervous system .
it plays a role in the repair of the 
 skin , nervous system , and hepatic tissues .
while the 
 estrogen level in women is not changed by acute exercise , it is suppressed by chronic 
 exercise16 .
kraemer et al . found an 
 increase in estradiol with mild exercise . during the luteal phase , the progesterone level 
 increases and exercise
nakamura et al . detected an increase in 
 both estrogen and progesterone after exercise in the mid - luteal phase .
the menstrual disorders observed in 
 female athletes result from differences in the release of oligomenore and amonore 
 gonadotropin releasing hormones , and the release of fsh and lh is decreased by exercise11 .
twelve healthy female soccer players with normal menstrual cycles ( regular for one year , 
 282 days ) were included in the study as subjects .
all of the subjects were conforming to the luteal phase period ( 22nd and 
 25th day ) according to body temperatures ( table 
 1table 1.the subjects characteristics ( n=12)age ( years)19.61.3 ( 1822)sports age ( years)5.40.7 ( 47)height ( cm)1664.7weight ( kg)55.45.7 ) . the experimental protocol of this study was approved by the local ethics committee .
all the 
 subjects were informed about the purpose and risks of the study before signing a written 
 consent .
the test 
 started with slow running ( 8  km / h ) , and the subjects ran 2 meters apart from each other 
 between two lines .
then , the same distance was run 
 again and the second run was started .
the running speed was adjusted by the signals and it 
 was increased by 0.5  km / h per minute .
the test was stopped when a subject failed to follow 
 the set pace of the  beeps  for two successive shuttles or stopped voluntarily14 .
all the subjects who completed the test were successful . the subjects 
 were instructed not to eat anything three hours before the exercise and not to do any sports 
 from two days before the exercise to control the test and these conditions .
afp , estradiol , progesterone fsh , and lh values were measured using an 
 enzyme - linked immunosorbent assay ( elisa ) and original kits in a laboratory .
repeated measure 
 anova was used to compare afp , estradiol , progesterone fsh , and lh serum levels at baseline 
 and immediately and 1hour after the test .
afp levels had significantly decreased after 1  h of recovery from exercise in 
 the female soccer players ( p<0.05 ) . in the female soccer players , estradiol and lh levels 

had significantly increased immediately after the exercise but had returned to resting 
 levels after 1  h of recovery ( p<0.05 ) .
progesterone levels had significantly decreased 
 immediately after the exercise but had returned to resting levels after 1  h of recovery 
 ( p<0.05 ) .
the 
 value of fsh1  h after exercise was lower than its value before the exercise ( p<0.05 ) 
 ( table 2table 2.repeated measure of anova comparison of pre and post ( immediately and 1-hour 
 after ) shuttle run test effect on hormone level ( n=12)pepsep1hseafp ( ng / ml)1.50.51.50.381.40.5*fsh ( mu / ml)5.52.46.22.75.12.4*lh ( mu / ml)4.83.55.634.94*estradiol ( pg / ml)96.75.5104.259.19558.9*progesterone ( ng / ml)6.45.95.456.16.2*pe : before exercise , pse : after exercise , p1hse : one hour after exercise ) .
our findings of heart rate before and after maximal aerobic exercise are 
 shown in table 3table 3.before exercise ( pe ) and after exercise ( pse ) heart rate values ( n=12)pepse heart rate ( pulse / min)63.15159.110.3*. pe : before exercise , pse : after exercise , p1hse : one hour after exercise
in the present study , the effects of acute maximal exercise on afp , estradiol , 
 progesterone , fsh , and lh in female soccer players during the luteal phase of the menstrual 
 cycle were researched .
afp is an oncofetal glycoprotein with a molecular mass of approximately 70 kd17 , 21 .
measurements of maternal serum 
 and amniotic fluid afp during pregnancy are important and widely applied in screening 
 methods for the detection of congenital anomalies of the fetus17 , 21 .
measurement of 
 serum afp plays an important role as a diagnostic or in screening tests for in certain 
 malignancies .
hepatocellular carcinoma is the most frequently occurring malignant disorder 
 for which afp is used as a biomarker17 , 21 .
other cancer types that increase serum 
 afp levels are pancreatic and gastrointestinal carcinomas , and germ cell tumors of the 
 testis or children s brains17 , 21 .
it is our supposition that decreases in the afp values , a cancer 
 parameter , taking place with exercise , could be used to determine the importance of exercise 
 in cancer treatments .
we found only one publication in the 
 literature concerning the change in afp with exercise . in a study of women aged over 
 seventy
, it was found that the afp level did not change with exercise5 . in our study ,
estradiol and progesterone are gonadal hormones which decrease with aging , and this may 
 lead to problems such as metabolic syndrome and sarcopenia16 . furthermore , estrogen also affects other endocrine responses 
 during exercise9 . while the effect of 
 exercise on anabolic hormones is maximal in the young women with normal menstruation , 
 estrogen and progesterone levels decrease more in the women with the menarche disorder11 , 25 .
consequently , female athletes may show menstrual disorders such as 
 amenore ( no menstruation ) , delay in the age of menarche , oligomenore ( frequency of 
 menstruation of more than 35 days ) and insufficiency of the luteal phase3 , 12 , 15 , 19 , 22 , 23 , 25 . in our study ,
it has been mentioned in the literature that chronic exercise 
 suppresses estrogen and progesterone25 . 
 in the present study
, the progesterone level had decreased 1 hour after the exercise a 
 result that is consistent with the literature . in female athletes , the pulsatile release of gonadotropin - releasing hormones decreases . 

this suppresses the release of lh and fsh from the ovaries ; therefore , the release of 
 estrogen decreases .
low luteinizing hormone levels explain menarche disorders and secondary 
 amenore in female athletes3 , 15 . in our study , lh increased immediately after the exercise 
 and returned to its former level after 1 hour .
this may show there is a positive effect of 
 acute exercise on lh . on the other hand , the decrease of the fsh level to under its original 
 value 1 hour after the exercise shows that intense exercise suppresses fsh .
this result is 
 also consistent with the literature3 , 15 , 19 , 22 , 23 , 25 . in the present study
the effect of maximal aerobic exercise in the luteal phase during 
 which athletes show the most menstrual problems on fsh , lh , estradiol and progesterone 
 hormones , and afp was studied .
the observed of suppression progesterone and fsh values is 
 the literature consistent with other reports while the increase of estradiol and lh levels 
 immediately after exercise shows that acute exercise can be used as a method of training for 
 female athletes . on the other hand , the significant decrease in the value of afp , which is a 
 cancer parameter , 1 hour after the exercise , may be of valuable in the future studies of the 
 relationship between exercise and cancer .
 [ purpose ] the performance of female athletes during their menstrual period has attracted 
 the attention of researchers for many years . it is known that the menstrual period changes 
 with exercise . alpha - fetoprotein ( afp ) is an oncofetal protein . in this study , 
 the effect 
 of maximal aerobic exercise in the luteal phase on some hormones and afp in female 
 athletes was researched . 
 [ subjects and methods ] twelve volunteers and healthy female 
 footballers with normal menstrual cycles volunteered for this study as subjects . 
 all the 
 participants performed a shuttle run test . 
 blood samples were taken before , after , and one 
 hour after exercise . 
 serum afp , estrogen , progesterone , follicle - stimulating hormone 
 ( fsh ) , and luteinizing hormone ( lh ) values were measured using an auto analyzer and 
 original kits . 
 heart rate measurements were performed before and after the exercise . 
 [ results ] afp activity 
 had significantly decreased after 1  h of recovery from the exercise 
 in the female soccer players , and estrogen and lh activity had significantly increased 
 immediately after the exercise . 
 progesterone activity had significantly decreased 
 immediately after the exercise . 
 fsh values had significantly increased immediately after 
 the exercise . 
 [ conclusion ] the results of the present study show there were significant 
 decreases in the values of afp , which is a cancer parameter , 1 hour after the exercise 
 . 
 this result may be valuable in future physiotherapy studies on the relationship between 
 exercise and cancer . 
INTRODUCTION
SUBJECTS AND METHODS
RESULTS
DISCUSSION