Table of Contents Introduction

Table of Contents
Literature Review…………………………………………………………………………………..3
Source 1……………………………………………………………………………………..3
Source 2……………………………………………………………………………………..5
Source 3……………………………………………………………………………………..7
Source 4……………………………………………………………………………………..9
Source 5……………………………………………………………………………………11
Presentation of Findings…………………………………………………………………………15
Processing of Findings…………………………………………………………………………..18
Reference List……………………………………………………………………………………22

This research is on the effect of sports and on the menstrual cycle. This topic is a problem in society because many girls and young women have missed periods due to sports and over exercising. This research is very important as it may help women to understand the causes of their missed period therefore know that to prevent this they must not over exercise. The menstrual cycle is controlled by hormones, the pituitary gland in the brain produces Follicle Stimulating Hormone and Luteinizing Hormone which then stimulate the ovaries to produce oestrogen and progesterone (Hacke, 2017). Together these hormones, through negative feedback, control the menstrual cycle. Anything that affects the hormonal balance will affect the menstrual cycle. The causes according to ‘The Femedic’ (Hacke, 2017) are stress, extreme weight loss and over exercising. Many women exercise so much that the body protects itself by conserving energy and thus preventing reproduction which stops menstruation. (Hacke, 2017). According to ‘The Journal of Clinical Endocrinology ; Metabolism’ (Warren, June 1999), amenorrhea causes the loss of the normal pulsatility of luteinizing hormone and the follicle stimulating hormone. Therefore, this interrupts the normal pulsating release of Gonadotrophin releasing hormone. (Warren, June 1999). Women should know that over exercising is very dangerous and that they should take caution to prevent missed periods.
This study will mainly consist of primary methods of research although there will still be some secondary research. This research will be conducted through a survey. The survey will be given to 50 females in total in the researcher’s school, Holy rosary School, and community, Bedfordview. The survey will be given out at random regardless if the recipient is sporty or not. The results will hopefully show that women will have missed periods if they over exercise. This study will be able to contribute to the vast body of knowledge as it will show the results of women who have had missed periods due to exercising at Holy Rosary School and Bedfordview.

We Will Write a Custom Essay Specifically
For You For Only $13.90/page!

order now

To determine the effect of Sports and exercise on a women’s menstrual cycle.

Lots of exercise and sports can cause disruptions in a women’s menstrual cycle which can result in a missed period.

Literature Review
Source 1
Title of article: “Missed period? Here’s how to figure out why”
Reference: Georgia Hacke, GH, (2017). The Femedic, (accessed 19 January 2018)
Hormones regulate the menstruation cycle and it is linked to many other body systems. According to this article follicle stimulating hormone (FSH) and luteinizing hormone (LH) stimulate the ovaries to produce oestrogen and progesterone and together through negative feedback, they control the menstruation cycle.

This article states that irregular periods occur at the start of puberty and around the time of menopause. An average menstrual cycle is 28 days although this article says it can be 21-35 days.

The Femedic states that stress, extreme weight loss and over exercising can cause a missed period. This can be a reason why missed periods occur mostly in female athletes and in women with various eating disorders. The body has evolutionary adaptions so that it can protect itself. It conserves energy by preventing reproduction which stops menstruation and therefore the body protects itself. This links back to the hypothesis that over exercising can cause a missed period and therefore that means that it causes disruptions in the menstrual cycle.

Validity- This source is valid as it is appropriate to my question and it is very relevant as it was published in December of 2017 and therefore has very recent information. It gave me all the information on how the body prevents reproduction to protect itself by conserving energy which shows how lots of sports and exercise can cause a missed period in a woman.

Reliability- This source is very reliable as it comes from a medical website that discusses medical issues. The article is also written by a doctor.

Usefulness- this source is very helpful as it has information on why the body stops menstruation when a person is over exercising themselves and this source also helped me understand my topic better.

Limitations- A limitation in this source is that it does not have a lot of information about my topic. The source starts to talk about other reasons on why a woman might have a missed period and does not go into detail about the reason which I am researching which is on how lots of exercise can cause a missed period.

Source 2
Title of Article: “Why does excessive exercise cause missed periods?”
Reference: Katrina Josey, 2017,
Amenorrhea is when a female misses one or more menstrual periods. Exercise-induced amenorrhea is a form of secondary amenorrhea which is when a person misses a period because of excessive physical activity. According to this article, amenorrhea occurs in 5-25% of female athletes.

Gonadotrophin releasing hormone (GnRH) is a hormone which is released every 60 to 90 minutes. This normal pulsating release of GnRH is interrupted when intense exercise stresses the body and this article states that less of the hormone will be released at each pulse. According to this article, amenorrhea will most likely occur when intense exercise is combined with low calorie intake and a low fat percentage. Going beyond an hour of aerobic activity is more harmful that good. There will not be enough energy in the body and that will disrupt normal hormonal and metabolic functioning.
Hormone changes that are associated with disruptions in the menstrual cycle can lead to infertility, heart disease and changes to bone density. Primary amenorrhea is the absence of menstruation after the age of 16. Secondary amenorrhea occurs when a woman is already menstruating and then has a missed period. According to this article the symptoms may include headaches, weight loss or gain, acne, cramping with no bleeding and changes in breast size. This could link to the hypothesis because the cause could be lots of sports and exercise.
Validity- This source is appropriate as it has very current information, on the causes of a missed period. It also has lots of information on amenorrhea and the reasons such as excessive exercise.

Reliability- I think that this source is very reliable as it comes from a health website “Livestrong” which deals with fitness and exercise. It is also reliable because the author of the article is Katrina Josey who is an exercise physiologist and health specialist in Ohio, USA. She is very experienced in the life cycle of developing health and wellness programs.

Usefulness- This source is useful as it gives new information on how to exercise in a healthy way but still be careful so not to cause amenorrhea. This information includes not doing more than 60 minutes of cardiovascular exercise each day.

Limitations- One limitation is that even though this source is from a website about health and is written by someone who is a health specialist, she might not know a lot about amenorrhea but only enough so that women who read the article are informed about it and can take precaution when they read the source.

Source 3
Title of Article: “Health issues for Women Athletes: Exercise-Induced Amenorrhea”
Reference: Michelle P. Warren, The Journal of Clinical Endocrinology ; Metabolism, Volume 84, Issue 6, 1 June 1999, Pages 1892-1896,
Women with exercise induced amenorrhea lose the normal pulsatility of LH and FSH because metabolic and environmental stress such as intense exercise and low-calorie intake (Josey, 2017). According to this source the frequent suppression cyclicity that is seen in athletes exemplifies the sensitive of the reproductive system to nutritional and other metabolic stresses.

Gonadotrophin releasing hormone pulse generator is affected when there is a complete suppression of the normal pulsatile secretion of GnRH as is reflected in the low levels of LH and even FSH. This source states that this could be because of weight loss or dietary restriction on the GnRH. There were studies that attempting to reproduce this abnormality in normal women and according to this source, it was found that energy deprivation affected the LH pulsatility and that exercising without energy deprivation did not. This shows that the hypothesis is true as lots of exercise can cause disruptions in the menstrual cycle and cause a missed period.

Many athletes will show some type of weight loss and dieting behavior. According to this source, they are often vegetarians and eat little red meat or they have a diet with iron deficiency.

Primary amenorrhea is when young ballet dancers who start training at age 8 or 9 may not menstruate until their early 20s. This is because exercising and sports can cause disturbances in the menstrual cycle. The normal is not affected but they are known to be taller and having longer limb length.

According to this source, women who have secondary amenorrhea show convincing evidence that hypothalamic amenorrhea that is associated with exercise is due to little calorie intake when over exercising a lot.

Validity- The source uses scientific methods and terminology and is appropriate to my topic as it explains why a period can stop in women and why some girls only start very late as they did sports and exercise very early on in their lives.

Reliability- This source is very trustworthy as this scientific article was published in a journal “The Journal of Clinical Endocrinology & Metabolism” in Oxford and was written by Michelle P. Warren who earned her medical degree from Cornell University Medical College and is trained in reproductive endocrinology. She was the first to realize that most skeletal problems occur in women because of menstrual irregularities.

Usefulness- This source is useful as it shows exactly what is affected by amenorrhea and what hormones are affected due to over exercising. This shows new information because it was not in any of the other sources which explains how sports and exercise can affect the menstrual cycle.

Limitation- The article is very old so the information might be outdated and all new information that has been discovered since is not shown in the article. This article was still used as it is very reliable as it was researched in Oxford and there is no false information.

Source 4
Title of Article: “Female Athlete Triad: Problems caused by Extreme Exercise and Dieting”
Reference: 2016, CITATION Kat17 l 1033 (Josey, 2017) CITATION Geo17 l 1033 (Hacke, 2017) CITATION War99 l 1033 (Warren, 1999) CITATION War01 l 1033 (Warren ; Perlroth, 2001) CITATION Hea17 l 1033 (Healthline Editorial Team, 2017) OrthoInfo, Diseases and Conditions,–conditions/female-athlete-triad-problems-caused-by-extreme-exercise-and-dieting/
Sports and exercise is done by many girls and women of all ages. When a young woman or a girl goes to extremes to exercise or diet, three connected illnesses could develop. This is known as the female athlete triad.

Disordered eating, menstrual dysfunction and premature osteoporosis.

The source states that females playing any sports can develop any part of the triad especially those who are in sports that rewards being thin or improved performance which can lead them to over exercising which might cause a missed period.

Disordered eating can be from anorexia nervosa to bulimia and females are more likely to have it. Problems that the illness can cause are dehydration, muscle fatigue and weakness, kidney damage and other serious conditions like not taking enough calcium can result in bone loss. Hormone balances can result in even more bone loss through menstrual dysfunction as with normal menstruation, oestrogen is produced which helps keep bones strong but with amenorrhea, levels of oestrogen is lowered.

In a normal menstruation, the body produces sufficient oestrogen and amenorrhea can cause the oestrogen level to be lowered. Stress fractures can also be caused by amenorrhea and a normal menstruation is needed for pregnancy.

Validity- This source has information on how the oestrogen levels are lowered because of sports which can affect the menstrual cycle and cause a missed period. All the information is relevant as it is very recent and was last reviewed in June 2016 and is very appropriate.

Reliability- This source is very reliable as it comes from a medical website that discusses many different diseases and many other medical conditions. It is also very current as it was last reviewed in June 2016 and has lots of new and updated information.

Usefulness- This source is very useful as it gave me information on the female athlete triad and how disordered eating and osteoporosis can also develop alongside menstrual dysfunction.

Limitations- A limitation could be that this article might not have been written by a professional or a doctor as there was no name provided for the source and in the source, it says that the information is for educational purposes and should not serve as medical advice.

Source 5
Title of Article: “Hormone and Sport: The effects of intense exercise on the female reproductive system.”
Reference: Warren, Perlroth (2001) Journal of Endocrinology 170, 3-110022-0795/01/0170-003.Online version-
According to the source, exercise has lots of health benefits but intense activities have a unique set of risks for a female athlete. Reproductive abnormalities in female athletes originate in the disturbance of the GnRH pulse generator and in hypothalamic dysfunction.
The hormone profile of women in low-weight sports is characterized by hypoestrogenism which results from the disruption of the hypothalamic-pituitary-ovarian axis. According to the source menarche occurs in girls when the body fat rises to 17% of the body weight and the menstruation is lost when the body fat decreases to less than 22% of the body weight. The source states that there have been experiments done that attempt to induce menstrual dysfunction in women and they have shown that exercise together with calorie restriction affects LH suppression and that exercise alone does not have any effect on LH pulsatility.

The source states that athletes who develop amenorrhea have a gonadotropin pattern which reverts back to a premenarchial pattern. The LH is therefore more suppressed than the FSH. This observed in ballet dancers shows a relationship between the activity level and discontinuation of menses.
Validity- This source has been written by two professionals and has been through the peer review process. It shows many other past studies that have been done on the topic.

Reliability- This source is very reliable as it comes from a journal article that was written by Physicians and Surgeons and that shows that this source is very reliable as these people are professionals and have studied the topic of the female reproductive system very well.

Usefulness- This source is very useful as it cites many past studies that have been carried out about my topic and this helps me and gives me an idea on how to research my topic. It gave me information on how hormones are involved in the female reproductive system.
Limitation- This source is very old as it was published in 2001 and so new discoveries made in recent years are missing.

Exercise is very health for the body but too much of it can be very damaging especially for women. Exercise without a lot of calorie intake is even more damaging. Amenorrhea might develop and this can result in bone loss which is very dangerous as it can lead to premature osteoporosis. When I am doing my research, I hope to only concentrate on exercise-induced amenorrhea and find out more on why it effects some women.

The study that was conducted to find out the effects of sports and exercise on a women’s menstrual cycle had 50 participants. The participants were all women and they were all aged from 16 to 50 years old. Women that were 50 years old were included in the study even though they might have been going through menopause because the survey asked if they had a missed period in the past which does not affect whether they are going through menopause or not. The experiment had 2 different groups. One group compared the number of people that had a missed period with how many hours they exercised. The other group compared the number of people who had missed period due to the activities they do, such as a sport, gym or sport and gym or no sport and gym.

The researcher conducted this experiment by means of a survey.

The questionnaire was given to the Grade 10, 11 and 12s at Holy Rosary School in Edenvale, Johannesburg with a consent form to inform parents of the experiment and to ask their permission for their daughter to do the questionnaire.

The researcher asked one girl in Grade 10 and one girl in Grade 11 to hand out the questionnaires and consent forms to others in their grade.

The researcher did this as the girls knew which people in their respective grades did sports and which girls did not do any sports.

The questionnaire was then returned to the researcher in 1-2 days time as the girls had to go home and get consent from their parents to do the questionnaire.

The participants that were over 18 were chosen at random.

The researcher went to Planet Fitness gym in Bedford Centre in Bedfordview to give out questionnaires to women who went to the gym.

The questionnaires were then returned immediately to the researcher as all the people were over 18 and they did not have to go and get consent from anyone.

The rest of the questionnaires were given by the researcher to random people all over the mall which was Bedford Centre.

The questionnaires were also distributed to family members of the researcher.

The results were looked over and divided into different groups of data and recorded into graphs and tables.

The participants were told what the research question was and informed on why the researcher was doing this research project. The reason for why this particular question was chosen was also told to the participants. The reason is that there are a lot of diseases associated with the female reproductive system in the researcher’s family and therefore the researcher found the female reproductive system very interesting. The researcher found the question very interesting and decided to research more into it. All the parents of the participants who were under 18 were also told about the research question and were asked to give their consent for their daughters to partake in the survey as information on periods is very private. The research question which is the effect of sports and exercise on the menstruation cycle does not disadvantage any group as most participants were told that if they did not want to partake in the survey, they did not have to. There was no risk to any of the participants as the experiment involved getting information about past missed periods and not inducing a missed period. The researcher made sure to tell all the participants that the information will remain anonymous as the participants would not have to write their name down on the survey and the researcher made sure to never look at what each of the participants had written on the questionnaire until it was time to analyse all the results. By the time the researcher looked at the results, the questionnaires were all mixed up and there was no way of knowing which person filled which questionnaire. The data was safely kept in a folder and was then added to the appendix.

Presentation of Findings
The data presented will show the effects that both sports and exercise has on the menstrual cycle. The data will prove the hypothesis that lots of sports and exercise will cause disturbances in the menstrual cycle and therefore cause a missed period. There are 50 participants in the data and are all aged from 16 to 50 years old and are all female as only females have a menstrual cycle. The data will be shown in two ways. First it will be shown in a table and the table will show the exact number of people and then that data will be converted into a percentage and will be shown on a bar graph. It will be converted into a percentage because each group does not have the same number of people so it would not be possible to compare the data unless it is a percentage.

Figure 1
A Table to show number of females with missed periods and the number of hours they spend exercising, either gym and or sport, every week.

Total hours spent exercising at either gym and or sport, every week Number of people with missed periods Total number of participants
0 3 12
1 0 5
2 4 10
2,5 1 1
3 3 4
4 5 6
4,5 1 2
5 0 1
6 4 6
8 1 1
10 1 1
10,5 1 1
Figure 2

Figure 3
A table to show number of females with missed periods and the physical activities that they do
Type of activity Number of females with missed period Total number of participants doing this activity
Sports 3 6
Gym 4 14
Both gym and sports 16 22
None 1 8
Figure 4

Processing of findings
Figure 1 and 2 is showing the number of females with missed periods and the number of hours that they spent exercising in the gym every week. Figure 1 shows the number of females who had a missed period and the hours that they exercise in the gym every week, the total number of participants is also shown. Figure 2 shows the percentage from the data in Figure 1 so that it is easier to compare the different results as each group did not have the same number of participants.

The graph suggests that the number of hours a female exercises may contribute to a missed period. The graph showed that women that did more than 6 hours of exercise in the gym all have had a missed period. According to “The Femedic” this is because they over exercise which stops the reproductive system as the body needs to save its energy for other important systems such as the circulatory system, (Hacke, 2017). An article from “Livestrong” suggests that over exercising is also dangerous as this can result in loss of lots of energy which can interrupt with normal hormonal and metabolic functioning, (Josey,2017).

The graph showed that 25% of women who did no hours of exercise in the gym also had missed periods. This could be because even though they did no hours in the gym, they might’ve still done some sports which means that they did some exercise which contributed to the missed periods.
The graph showed that 100% of women who did 2,5 hours of exercise at the gym every week had missed periods. This could be because only 1 woman did 2,5 hours of exercise at the gym as seen in Figure 1 and so the result would be 100%. The female could not have had a proper diet and this could be the reason for the missed period (OrthoInfo), 2016.
Women who did exercise at the gym for 1 hour and 5 hours in this sample had no missed periods. 1 hour every week is not a lot of exercise and therefore it cannot really contribute to a missed period. Women who exercised at the gym for 5 hours a week had no missed periods as they had a good diet and they did not exercise 5 hours at once in a day but paced themselves when exercising during the week.

These results are really similar to Warren and Perlroth (Warren & Perlroth, 2001) as they explain in their journal that intense exercise can result in reproductive abnormalities with the disturbance of the GnRH pulse generator.
This result is the same as it mirrored the survey done by the researcher. Both researchers used random participants and there was a variety of participants (those who did exercise and or sports, and those who did not).
Figure 3 and 4 show females who have had a missed period and the physical activities that they partake in. Figure 3 shows the exact number of females who have had a missed period and the physical activities that they partake in and it also shows the total number of participants. Figure 4 shows the percentage of the data from Figure 3 so that is easier to compare the data as the number of participants in each group were not the same.
Figure 4 shows that 73% of females who do both gym and also do a sport have had a missed period. This is because the women over exercise a lot when they do both a sport as well as going to gym. An extract from ” The Journal of Clinical Endocrinology & Metabolism” says that this causes FSH and LH to be suppressed as there is a lot of stress on the body CITATION War99 l 1033 (Warren, 1999).
Only 13% of women who do no physical activity have had a missed period. This result is expected as they do not have any stress on the body and those that did have a missed period were on medication or there were probably some other reasons such as stress, a low body weight due to eating disorders, birth control and medical conditions such as Polycystic ovary syndrome, chronic disease such as diabetes and celiac disease or thyroid issues CITATION Hea17 l 1033 (Healthline Editorial Team, 2017).
The results for women that play only sports was that 50% of them had missed periods and 29% of all women who only go to gym had missed periods. These two groups had women that had missed periods as they were exerting stress onto the body. This result was less than the group that did both gym and a sport together as doing both gym and sports exerts more pressure and stress on the body than those females who did only sports or only went to gym.

This result was very similar to the result from “The Journal of Clinical Endocrinology & Metabolism”( Warren M.P, 1999) as it showed that more intense sports had females with more menstrual irregularities than those who did not do any physical activity. The two studies were similar as both had different women who all did different activities.

The two studies were slightly different as well as “The Journal of Clinical Endocrinology & Metabolism” used different sports such as ballet and weight-bearing and non-weight-bearing sports and females who did no sports to compare how the menstrual irregularities would differ. This study did not use the specific type of sport but rather sports in general and also whether a female goes to gym and if she does, how long she exercise for every week?
This research has added to the body of knowledge in the world as the study has not been done before with participants at Holy Rosary School in Edenvale, Johannesburg as well as in Bedfordview. Therefore this adds new research into the field.

This experiment was done to find out whether sports and exercise is responsible for and will contribute to missed periods in various females. The experiment found that over exercising in women causes missed periods because it interrupts the normal pulsatility of the hormones LH, FSH and GnRH. The body gets put into a lot of stress because of all this exercise and it therefore has to conserve its energy for important systems of the body such as the nervous and circulatory systems of the body. Therefore, the body prevents reproduction which will prevent normal menstruation. The same thing can be said for the result of this research which is that intense exercise such as doing both a sports and gym together for many hours and over exerting the body past its limits can cause a missed period.
This proves the hypothesis which was: Lots of exercise and sports can cause disturbances in a women’s menstrual cycle which can result in a missed period.

One limitation which could be rectified is having the same amount of people in each group. If there is the same number of people in every group, then it is much easier to compare the results of different groups than just converting the data into a percentage. This could be rectified by making sure that every group has the same amount of people.
Another limitation is that the hours of exercise asked on the survey only applied to exercising in a gym. The survey should have asked how many hours of exercise the women did in total every week and not just at the gym. This is so that a more accurate result could have been obtained.
Recommendations for future studies on this topic is to also consider the ages of the women and compare how age would also affect the menstrual cycle.

BIBLIOGRAPHY Josey, K., 2017. Why does excessive exercise cause missed periods?. Online Available at: 2018.

Hacke, G., 2017. Missed period? Here’s how to figure out why. Online Available at: 19 January 2018.

Warren, M. P., 1999. Health issues for Women Athlethes: Exercise Induced Amenorrhea. The Journal of Clinical Endocrinology & Metabolism, 1 June, 84(6), pp. 1892-1896.

Warren & Perlroth, 2001. Hormones and Sport: The effects of intense exercise on the female reproductive system. Online Available at:
Healthline Editorial Team, 2017. Why is my period late: 8 possible reasons. Online Available at: 3 July 2018.

Anon., 2016. Female Athlete Triad: Problems Caused by Extreme Exercise amd Dieting. Online Available at:–conditions/female-athlete-triad-problems-caused-by-extreme-exercise-and-dieting/Accessed January 2018.