When we think about the menstrual cycle impacting exercise performance, we often only think about it during the stage of the period. But, the hormonal changes throughout the entire menstrual cycle and their impact on energy levels and mood can impact exercise performance all month long.
First a little look into what the menstrual cycle is.
The Menstrual Cycle
The menstrual cycle is the time from the first day of a woman’s period to the day before her next. The average cycle length is 28 days but regular cycles that anywhere between 21 and 40 days are also normal. (https://www.nhs.uk/conditions/periods/fertility-in-the-menstrual-cycle/)
The menstrual cycle can be broken up into phases. For the sake of this article, I’m going to refer to a 28-day cycle.
Week 1 & 2 or days 1-14 are the Follicular phase. Ovulation happens at around day 14. Week 3 & 4 or days 15-28 are the Luteal phase. For most women, the Luteal phase is 14 days and it is the Follicular phase that changes in length depending on the cycle length.
Estrogen and progesterone are both hormones secreted by the ovaries. They are important for sexual and reproductive development, help to regulate a woman’s menstrual cycle and have a key role in pregnancy.
Testosterone is another sex hormone also produced in the ovaries. Whilst we mostly associate it with men, everyone produces testosterone to some level and it plays an important role in women’s reproductive health among other things like breast and bone health.
At the start of the Follicular phase, when your period starts, levels of both estrogen and progesterone are low. Roughly periods last between 3 and 7 days and this can vary each month. As the period ends, levels of estrogen will begin to rise until ovulation. Just before ovulation, there is also a spike in testosterone. It is around this stage that you’ll feel most energetic.
Post-ovulation you enter the luteal phase where estrogen decreases and progesterone increases. The second week of the luteal phase is usually where premenstrual symptoms (PMS) start to appear such as mood swings, headaches, bloating, tiredness, spots, feeling irritable and change in appetite.
If you want to learn about the menstrual cycle in-depth I recommend watching: The Menstrual Cycle
What does this mean for exercise?
This is based on an average 28-day cycle and is a generalisation. The best way to find out how you feel and perform at different stages of your cycle is to keep a diary of how you feel before/during/after exercise, what stage of your cycle you’re in and any symptoms you’re experiencing. The more data collected the better understanding you will have.
Week 1 - During week 1 of your cycle you should aim for whatever you feel like you can do. How you feel during your period will be different for everyone. Some women will have lots of energy, no symptoms and can carry on exercising to high intensity. Others will have much harsher symptoms and will want to stick to the gentle movement.
Week 2 - With levels of estrogen still rising you’ll feel more energetic and recover faster after training. As you get closer to ovulation the spike of testosterone means you’ll normally feel even stronger and perform better (a great time to plan in fitness tests). This week is a good time for higher intensity workouts or lifting heavier, etc.
Week 3 - Estrogen levels peak at ovulation and then start to decline as progesterone increases. This can leave you feeling tired and sluggish. During this week aim for more volume over intensity in your workouts (i.e. less weight for more reps, or slower longer runs). And remember to be kind to yourself if your performance isn’t as high as last week.
Week 4 - Estrogen and progesterone decrease here, PMS symptoms start to appear and recovery between sessions is slower. Continue exercising at a low intensity, high volume or just doing whatever you feel up to.
How you feel during your cycle is completely unique to you. You might be able to go through your whole cycle working out to high intensities, or you may have weeks where light, gentle movement is all you can do. Every cycle will be different too. One month you may feel super sluggish with a lot of PMS symptoms and the next you could be absolutely fine.
By being in tune with your body and picking up trends each month it can help you plan your workout programme effectively to work with your menstrual cycle instead of against it. For example, if strength is your goal you could plan a block of training to end with 1 rep max testing towards the end of week 2 when you’re at your strongest, rather than on week 4 or 1 when you’re less likely to perform your best.
So next time you have a bad workout, feel frustrated and like giving up. Think about where you are in your cycle. Do you have less energy or more PMS symptoms than usual? Keep a note of this so in the future you can plan more appropriate workouts for yourself at this time and figure out the ideal times to push yourself harder.
What about nutrition?
Numerous studies have shown that women burn more calories during the luteal phase of their cycle. Estimated from 100-300 calories a day and some even up to 500. This could explain why you feel hungrier and have more cravings at this stage.
It also means that if you were to start eating in a deficit at this point of your cycle it could actually be harder to stick to. Think about it, if you start eating in a calorie deficit and slip up after only 1 or 2 days you’re more likely to sack it all in. If you start at the start of your cycle and have a whole 2 weeks before you hit your hungrier phase then you’ll have more motivation to stick to it as you’ve already done it for 2 weeks so you know you can.
In addition, if you know you usually feel hungrier in the second phase of your menstrual cycle, then you could allow yourself to eat a little more here. Remember deficits don’t work on a day to day basis, it’s over the longer term that counts. So if you eat in a deficit for 2 weeks and then eat in a smaller deficit or even at maintenance for 2 weeks over the course of a month you’ll still be in a deficit. Yes, you’ll lose weight a little slower initially but you’ll lose it quicker over the long-term if it’s something you can stick to.
And if you stick to dieting for the whole month, remember when you’re in the Luteal phase of your cycle you can eat an extra couple of pieces of fruit each day to give you that extra needed energy.
Again it’s about understanding how you feel during your cycle and adjusting your nutrition accordingly. You could do this by keeping a food diary alongside how you’re feeling and look for trends for when you’re more likely to reach for the evening snacks or take away because you don’t feel like cooking and when you find it easiest to stick to a nutritious, balanced diet. (I’m not talking about the takeaways you treat yourself to with your family at the weekend here, more the ones you quickly pick up because you don’t have the energy to cook).
If you want to start tracking your fitness read Should I Track My Fitness
Even if you’re not tracking your food, you might want to try eating a little more before or after your workouts during the Luteal stage to help fuel your workouts and aid your recovery. As I mentioned above energy and recovery time tends to decrease in this stage so anything you can do to help it will be a positive.
As with everything in your cycle, it’s unique to you. So don’t take what I’ve said as gospel. Instead, take some time to learn about your cycle and go with what works for you.
Comments