Following on from my previous blog where I touch on the differences between men and women’s hormones. If you haven’t read it yet you can check it out here

A woman’s menstrual phase will also have an impact on her ability to lose body fat and her performance in training. If you look at the 28 day cycle (and most women are not actually on a 28 day cycle – I am not unfortunately!) there are two major hormones at play – estrogen and progesterone. The graph below represents a 28 day cycle – ovulation (releasing of the egg) at 14 days is right in the middle of the cycle, estrogen is dominant in the first half of the cycle and progesterone more dominant in the second half.


Estrogen is usually labeled as the “bad” hormone and linked to fat gain, however estrogen actually plays a very beneficial role in the female body. Estrogen has been linked to decreases in appetite, increases in insulin sensitivity, it increases fat burning enzymes in skeletal muscle, protects muscles from soreness and during menopause when estrogen drops off it can cause an increase in fat storage. It has also been shown that a woman responds better to training in the first half of the cycle when estrogen levels are higher, more on that later.

Progesterone on the other hand can cause increases in hunger and cravings, it has actually been linked with an increase in metabolic rate however it’s usually mitigated with the increased food intake from the cravings (you know that chocolate you crave right before your period? Research says some women will consume approximately 500 extra calories per day in this phase!). It has been shown to cause slight insulin resistance, decreases in protein synthesis (building muscle) and increases in protein breakdown which makes it more difficult to adapt to training. This really is the nasty hormone.

Some women will be lucky and have little to no response to their hormone cycle. But for others, they can be dealing with a completely different physiology in every week. Week 1 at the start of the menstrual cycle they may be stronger, week 2 a little weaker, week 3 may have a slight peak in strength due to the small increase in testosterone right at ovulation and week 4 the PMS stage all hell can break loose. Not only are there strength decreases, some women lose coordination, their brain function is disrupted and they become highly emotional. PMS is completely individual, it can effect some women and have absolutely zero impact on others. I know for me personally it’s not consistent, some months it does and I become weaker the few days before my period and my pelvic floor is completely not working (ooops!). Other months is like nothing is happening and there are no changes whatsoever. The best thing to do is to track things for yourself and if you are aware that you have these symptoms it could be a good idea to plan your deload week around this time and avoid heavy, high coordination work in that week.

So what can we do to put ourselves in the best position to be successful with fat loss? If your menstrual cycle is regular and you are going to start dieting for fat loss then it could be advantageous for you to start the diet in the first week when your period starts, this is when your appetite and hunger are down. Starting mid cycle when hunger is higher will be mentally a lot tougher and you may have issues with adherence. Hunger is higher in the second half but you are burning more fat as fuel so if you are strong willed you can use this to your advantage and see greater results. Fuel your body with higher carbs and lower fats in the first half of your cycle when your training is more productive. Increase protein and fats in the second half and reduce carbohydrates as your training reduces. If you are aware of these processes going on within your body and you can control and adapt what you are eating through each cycle you may just lose that last bit of body fat that doesn’t want to budge.

Overall for most women – increasing protein, using carbs around your training and adding heavy weight training to your program will create a greater response and produce huge results! Lifting weights does not make you bulky!