Periods and Sport – 5 Things to Consider
1. It is never normal to attribute not having regular periods to your training or sport.
Attributing a lack of periods to training “hard” is probably one of the most common misconceptions in the sporting environment. A regular menstrual cycle is a sign of a health hormonal balance and irregular or absent periods is an indication that this balance has been affected. The female hormones (oestrogen and progesterone) that drive our menstrual cycle are not only important for beneficial adaptations to exercise but have far reaching effects throughout the body. One of the important roles these hormones play is their positive effect on bone health. Oestrogen reduces the amount of bone that is broken down and so helps to prevent low bone density. Any condition that reduces the number of years that a woman produces oestrogen tends to increase the risk of osteoporosis. Therefore, an absence of periods can have implications for bone health, as well as affecting reproduction and fertility function.
There are many reasons why a woman’s menstrual cycle can be disrupted and having a low energy status with training is one of them. This is termed “Relative Energy Deficiency in Sport” and essentially means there is an imbalance in energy intake (nutrition) and energy output (sport/training). A low energy status can occur when our dietary intake is insufficient to provide energy for all the bodies physiological functions and physical activity requirements. This energy deficiency can result from excessive exercise, poorly planned nutritional intake, not enough nutritional intake, or not enough recovery. One of the first signs of a low energy status that a woman may notice is that her periods may become irregular or absent. It is important that this is always discussed with a medical professional so that that the underlying cause can be identified and appropriately managed.
2. Do not underestimate the effect heavy menstrual bleeding can have on your training and health.
Every woman has a different perception of what heavy menstrual bleeding means to them. Medically, it is defined as losing 80ml of blood or more in each period, having periods that last longer than seven days, or both. But practically, if a woman has a bleed that requires regular tampon or towel changes (more than every 2 hours) or if they are passing blood clots, they may have heavy menstrual bleeding. In women who undertake regular training or sport, this can be very inconvenient both in practical terms and from the associated symptoms that some women can experience with feeling lightheaded and fatigued.
An additional concern is that heavy menstrual bleeding can put women at higher risk for iron deficiency due to the monthly blood loss and in women that exercise and train regularly, it is acknowledged that this risk can be greater.
Iron is a mineral that has several important roles in the body including energy metabolism and oxygen transport to our tissues and organs. Iron is lost through sweat, skin, urine, the gastrointestinal tract, and menstruation. In particular, high intensity and endurance exercise, increases iron losses by as much as 70% when compared to sedentary populations. Red blood cells also break down more quickly in those who exercise. If iron deficiency becomes more severe, anaemia can develop, and women can report general fatigue with exercise and decreased sporting performance. A rather more unusual feature of iron deficiency is the development of “pica” or cravings for things that are not generally meant to be eaten such as ice.
It is important that women can recognise and seek medical help for heavy menstrual bleeding and related symptoms associated with iron deficiency. Iron deficiency is diagnosed through simple blood tests, the most useful of which is ferritin, which is a marker of iron stores. Every woman’s physiology and training demands are different, so ferritin goals will vary from person to person and needs to be individualized.
Replenishing iron levels through dietary means is always preferable to taking an iron supplement. However, depending on your iron level, supplementation may be necessary.
Discussions and education of potential symptoms with heavy menstrual bleeding in exercising women is required so that women can flag if they may need further assessment. There are also practicalities that need to be considered around sportswear and women feeling comfortable when training.
3. Understand how pre-menstrual syndrome may affect your sporting activities.
Premenstrual syndrome (PMS) is the name given to a group of emotional, behavioural, and physical symptoms that some women experience in the weeks before their period. Previous studies have shown that up to 90% of women have experienced some form of PMS during their reproductive years. PMS occurs during the luteal phase of the menstrual cycle (after ovulation) and spontaneously diminishes within a few days after onset of a period.
Common physical symptoms include breast tenderness, headaches, musculoskeletal pain, and abdominal swelling. Psychological and behavioural symptoms can include low mood, irritability, changes in appetite, fatigue or lethargy, sleep disturbances, loss of co-ordination and poor concentration. Each woman’s symptoms can be different and vary from month to month in both the nature and severity of symptoms. The clinical diagnosis of PMS can be made by a medical practitioner evaluating a woman’s symptoms /cycle and by excluding other physical and psychological causes.
The impact of PMS on a woman’s sport performance is very individual and may depend on their physical activities and training load. It is important to recognise that in team sports, it is not only the athlete, but other members of the team that can be affected by a player’s mood changes or perceived erratic behaviour. This can adversely affect team dynamics.
Management of PMS is helped by keeping a record of symptoms and the impact this has on your training activities. There are different medications that can be used for symptom control and these can include oral contraceptives, types of antidepressant medication and non-steroidal anti-inflammatory medication such as ibuprofen. But whilst these may be effective for many women with PMS, they can be linked with unwanted adverse effects and many women wish to manage with nutrition and psychological techniques.
Many women wish to manage their symptoms more naturally with nutritional means. Vitamin and mineral supplements may be effective in alleviating PMS symptoms. Vitamin B, vitamin D, calcium, and magnesium are essential for neurotransmitter synthesis and hormonal balance, both of which are potentially involved in the underlying pathogenesis of PMS.
4. If considering contraception – understand your choices.
Hormonal contraception is a choice for all women and can be used not only for birth control, but also to alleviate symptoms of heavy or painful periods, reduce the occurrence of premenstrual syndrome and in other medical conditions such as symptomatic fibroids, endometriosis and polycystic ovarian syndrome. In women undertaking regular sport, some choose to use the combine oral contraceptive pill to manipulate and control the timing of a withdrawal bleed that occurs during the seven-day OCP free days.
In general, contraceptive pills act by “downregulating” the production of sex hormones through a constant release of low doses of synthetic oestrogen and progesterone. Throughout the “artificially” induced cycle, the hormone concentrations for both oestrogen and progesterone stay at levels comparable to the menstruation phase of women who do not take the pill. So, does taking these hormones affect how we train and perform?
Currently, scientific research on how periods and the oral contraceptive pill affect athletic performance is lacking in both the consistency and quality of studies. One recent research article that evaluated a number of studies has suggested that OCP use might result in slightly inferior exercise performance on average when compared to naturally menstruating women. However, it was noted that the effect was trivial and there were inconsistencies across studies. Therefore, a women’s choice of contraception is individual and considerations given to practical implications of taking pills when travelling, whether you prefer a bleed or no bleed preparation and side effect profiles.
In the end, the impact a woman’s period or contraceptive use has on her performance is highly subjective and individual. For example, former British tennis player Heather Watson exited the first round of the Australian Open in 2015 due to what she called “girl things”. She reported symptoms of dizziness, nausea, low energy levels and spells of feeling light-headed. These symptoms can be common to many women, highlighting the need to discuss and evaluate how your menstrual cycle affects you.
For many sporting women, their choice of contraception is individualised and may come down to practicality, side effect profiles and ease of use with training and sport.
5. Does the menopause affect my training and sports performance?
The menopause is a transition phase from the reproductive to the nonreproductive phase in a woman’s life. It is a diagnosis that is made retrospectively by the history of a woman’s symptoms, with a natural menopause being recognized to have occurred after 12 months of absent periods (for which there are no other medical causes). The perimenopause is the “transitional” phase that may last for 3–5 years prior to a woman’s actual menopause and is associated with a natural decline in oestrogen levels and other important hormones that effect our bones and muscle protein. This naturally changing hormonal status alters a woman’s body fat distribution, by increasing our visceral fat mass (body fat that is stored within the abdominal cavity), as well as decreasing our bone mass density, muscle mass and strength.
So how does the natural decline in oestrogen and other hormone levels affect our sports training and performance? Many studies have examined this association, and some have shown that postmenopausal women may have reduced physical function in some capacity compared to premenopausal women. However, results have been contradictory, and it is still unclear whether the associations observed between the menopause and performance are independent of the changes seen with natural aging. It is well established that aging is associated with a decline in muscle mass (known as sarcopenia) and in women, there can be an accelerated decline after the 5th decade. In postmenopausal women, some important factors can contribute to this decline in muscle mass, such as reduced physical activity, protein intake and oxidative stress. It is still uncertain whether in post-menopausal women, the associated low concentration of oestrogen accelerates or adds to this decline in muscle function.
However, when it comes to our bones, the science is clear and we do know that postmenopausal women are susceptible to primary osteoporosis, as this is closely related to oestrogen deficiency. In women, the ovaries make oestrogen from puberty through to the menopause and any condition that reduces the number of years that a woman produces oestrogen increase the risk of developing osteoporosis. It is around four times more common in women than men, and particularly in women who have been through the menopause.
During the menopausal transition period, the reduction in oestrogen leads to more bone resorption than formation meaning that the average reduction in bone mineral density is about 10%. Approximately half of women are losing bone even more rapidly, perhaps as much as 10%–20% in those 5–6 years around menopause.
There are many factors that influence our bone density, including our genetics and we also know that women who reach a high peak bone density when they are young, are less likely to develop osteoporosis.
But what can you do to help and improve both your bones and muscles as you transition through the menopause? Although you can’t change your genetics, there are ways in which you can help yourself. From the age of about 35 years, there is a slow loss of calcium from the bone in both sexes, but this increases during the menopause transition because of the reduction in oestrogen. Vitamin D helps your body absorb and use calcium, which gives your bones the strength and hardness.
Vitamin D is made in the skin in response to sunlight, but in the UK, adults should consider taking a daily supplement containing 10 micrograms of vitamin D especially during autumn and winter. Nutritional sources of Vitamin D are also important to consider such as with oily fish, eggs, red meat and fortified cereals. To increase our calcium levels, women should aim for two to three portions of calcium-rich foods every day.
Further key steps that should be followed with a balanced diet rich in protein and a healthy lifestyle reducing alcohol consumption and not smoking.
From an exercise perspective, it is established that physical activity has an important role in both preventing and ensuring we maintain strong bones and muscles. Resistance training helps by improving muscle mass and strength. Recent studies suggest that progressive resistance therapy 2–3 times per week is the most beneficial exercise. Balance exercises should also be incorporated because of the increased risk of falls and fractures after the menopause. Aerobic exercise improves muscle protein synthesis and muscle quality. It also reduces intramuscular fat.
