Female hormones and exercise
When it comes to exercise, gender plays a big part. In fact we should be looking more at our hormones when it comes to exercise than doing the same as males. Because its safe to say, we have a lot more going on with our hormones that can impact performance, weight loss, weight gain, muscle gain and tone.
Did you know that many of these sport related studies on muscle mass and tone as well as weight loss are based on cohorts of men and only 6% are based on women! Therefore, there’s a big gender gap when it comes to how our body responds to different sports, exercises related to our hormones as well as the effect these sports have on our hormones.
Our hormones influence more than just our reproductive system. Oestrogen and progesterone can influence our performance and training as well as recovery time and wellbeing. This is also the case with how we sleep that can impact on our overall wellbeing.
Exercise has been shown to reduce stress levels and also help regulate your hormones, such as insulin, but intense exercising can have detrimental effects on the female body including disruptions in the luteal phase and the loss of periods called amenorrhea which can also tie in with low carb.keto diets and high intensity training. Studies have also shown that during intense exercise, cortisol, prolactin, and TSH levels increase.
Exercise has been shown to reduce stress levels and also help to regulate your hormones!
Muscle glycogen is the key component in exercise performance and there are several factors which are known to affect its storage within muscles, these include dietary practices, physical activity, rest-recovery, and hormonal status.
Oestrogen actually increases muscle glycogen storage at rest, and spares glycogen utilization during exercise owing to increased free-fatty acid oxidation. Therefore Oestrogen levels affects a woman’s exercise metabolism.
During the luteal phase of the cycle where oestrogen levels are at their highest, results in a reduced utilization of muscle glycogen as an energy source (i.e. glycogen sparing effect) which is probably down to the enhanced reliance on lipid metabolism.
Oestrogen enhances the activity of lipoprotein lipase, increases circulating growth hormone levels, and decreases circulating insulin levels; all of which promote lipolysis.
Therefore, utilise the follicular phase when oestrogen is at its lowest when the body is more resilient to stress and high intensity training. Obviously, we are all different so we need to listen to our bodies cues, but we are also surrounded by information that suggests that during our period we are unable to do as much training, exercise and must rest but this is not always the case, in fact this could be the best time to support muscle tone and performance.
Iron status plays a big role in our energy levels and can also affect our hormones and intensity of training that our body can do. Heavy menstrual bleeding which affects a quarter of women can interfere with physical activities and can also result in iron-deficiency anaemia. So, for women that train a lot and experience heavy periods, iron stores can be constantly low which will affect thyroid hormones, metabolism and hormones status. It is advisable to get iron levels and thyroid hormones checked to make sure that you are supporting levels and ensuring the best performance and recovery during training.
Sleep quality is a big factor in how we feel, in fact both oestrogen and progesterone play a role in sleep quality. Women with symptoms of Premenstrual syndrome (imbalance of hormones) often have interrupted sleep and especially during menopause when hormone levels decrease, can cause even more issues with sleep, such as frequent waking, trouble falling asleep and staying asleep, night sweats and hot flashes. Lack of sleep can compromise not only your hormones but also your training, resulting in poor recovery, low energy and muscle fatigue.
Studies have shown that poor sleep can impact not only on training and performance but also muscle glycogen storage, muscle strength, recovery time, low mood, and increased appetite through poor insulin sensitivity.
The oral contraceptive pill can also have an effect on training outcomes and muscle gain and tone. A study from the Journal of Strength and Conditioning Research showed that women that were on the contraceptive Pill such as progestin which is a synthetic progesterone, had significantly lower DHEA, DHEAS and IGF-1 and much higher levels of cortisol the stress hormone. DHEA, DHEAS and IGF-1 all play a role in muscle growth and tone. This is down to the progestin binding to the same receptors as the DHEA and IGF-1, therefore they are unable to get into the cells and their muscle-growth activating properties do not work.
Another study that used a contraceptive pill with high levels of oestradiol increased muscle size but not muscle strength.
The contraceptive pill also reduces the VO2 max peak which is the highest amount of oxygen you can use during exercise, reducing your ability in high intensity training and can even result in oxidative stress in the body.
They also effect the status of nutrients within the body needed for hormonal balance, energy production and performance including magnesium, zinc, Folic acid, B2, B6, B12 which are all responsible for energy production and Vitamin C which helps the bodies stress response, the immune system and reduce oxidative stress and Vitamin E.
Calorie-restricted diets may also result in insufficient quantities of magnesium, iron and phosphorus. Phosphorus is shown to improve aerobic capacity and magnesium is related to strength improvement.
Magnesium is essential for over 300 chemical reactions within the body including hormonal balance, energy production, sleep, mood and muscle relaxation as well as aid muscle recovery.
Foods high in magnesium include cacao, spinach, nuts, seeds and wholegrains.
Making sure to hydrate effectively during training is important but also the phase of our cycle has an impact on how much water you should drink.
The need for fluid changes throughout the cycle and can impact on exercise. During the luteal phase after ovulation, there is a decrease in exhaustion time from higher body temperature, so make sure to pay attention to water intake during that time.
Water retention that many women suffer is a secondary effect of oestrogen and progesterone when they peak in the luteal phase. This water retention creates a drop in plasma volume which compromises the amount of oxygen that is delivered to the muscles, which results in reduced sweat rate which is needed to keep the body cool and can then increase body temperature meaning that more water is needed.
Let’s talk carbs and protein… we’ve all been hearing the eat more protein, but our phase can effect how much protein our body needs. Progesterone during the luteal phase actually increases the bodies need for protein. Protein catabolism which is the breakdown of muscles and other protein stores for cellular processes is highest in the luteal phase when progesterone peaks. Therefore we should be aiming for higher protein intake during this time.
Carbohydrates although often avoided by many people are essential for hormone balance. We need them for thyroid health, metabolism, and energy levels. Research shows that in a fasted state, women’s exercise performance was better in the follicular phase but when fuelling with carbohydrates, women performed better in the luteal phase. This is down to the oestrogen and progesterone peaking in the luteal phase which suppresses gluconeogenesis that utilises energy stores in the body. Therefore carbohydrates become essential during exercise in this phase.
Ever heard of carb loading…well evidence has indicated that glycogen loading does not occur in the same manner for males and females, thus affecting performance! Generally it was advised to directly prior to competition have traditionally included an intense glycogen depleting training period of approximately two days followed by a glycogen loading period for 3–4 days, ingesting approximately 60–70% of total energy intake as carbohydrates. However these studies were conducted on men and therefore do not represent metabolic differences and hormonal status. One study showed that women had significantly less glycogen depletion than men during running, and that women oxidized significantly more lipid and less carbohydrate and protein compared to men during exercise. Studies have shown that women tend to utilize more fatty acids from adipose tissue during submaximal exercise, whereas the main source of increased fatty acid utilization at rest is from skeletal muscle.
So what does this all mean…best advice is don’t train like a man! Listen to your body and your hormones and try to factor them in when you are exercising, training, or training for an event. But also make sure that you get your hormone levels checked and your nutrient status checked to ensure that levels are balanced to ensure the best performance and ability.
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