Period and watts

I’ve been riding for a few years, however this is my first season training with power… so I’m learning a lot of new things about my body. I’m currently in SS 1 and I’m on my first regeneration week which also is about to coincide with my period.
I’ve been strong through all my SS intervals except the days leading up to and the first few days of my period. These few days I can not sustain watts and energy by drastic amounts. My z2 is hard to muster and forget about sustaining SS intervals for longer than 3-5 minutes… which still takes way more mental and physical strength than normal.
Yesterday’s regeneration plan was hold 180 for 9 minutes with 4.3 minutes at 118 recovery x 4.
Instead of continuing to push through frustration and impossible physical ability, I decided to just do what felt best or felt closest to z2 which was around 80-90 watts, but my normal z2 is 118-147 and I normally feel good riding just a few watts in the 150’s as well.
I’m very interested in learning more about this trend where my watts and power just drop for a few days leading to and the day(s) of period. Do other women experience this? Is it as extreme as my power weakness? How do women race “A” races if that day coincides with their weakest power output?


Hey @lindsay.marx !
I can absolutely promise you that you are not alone here and I am very glad that you brought this up as it is something we need normalize talking about. As Stacy Sim’s says… “Women are not small men, stop eating and training like one.” That is a bold statement, but it is true. Your diet and training plan need to be tailored to your cycle to use your hormones to your benefit, not your detriment.

Its great that your rest week falls on the week of your period, but even then you may need to adjust your plan some. If you are having pms really bad, it is unlikely that you will be able to put out any power. So if your plan calls for intervals, reduce them by either intensity (e.g. do tempo instead of SS) or simply stick to zone 2/3 and add in a little time if you can to achieve a similar TSS score. Ideally you do not want to be racing during this phase when your progesterone and estrogen are high, as this has many impacts on performance which I will include details on below… but one of them is lower pain tolerance. If you are racing during this time (also known as the luteal phase), know that mental toughness will go a long way! You can also improve performance by consuming more carbs during and immediately after training , increasing protein intake both before and after training, increasing fluid/electrolytes and using caffeine to improve focus/reaction time and to reduce RPE.

I am so passionate about educating our Lady FasCats on this and showing them that they CAN perform well despite their cycles… that I stayed up late last night to make a chart to share with you all that will help you understand your cycle and can be used to tailor your training so that you take advantage of when you are at your best :slight_smile:


Thank you @Lacey_Rivette amazing chart! On my educational journey yesterday, I found an app sponsored or created by Stacy Sims called Wild AI

And I’ve been super engrossed with it. I can’t believe it’s a free app because there’s so much info.

I’m so glad to know it’s normal too! Seeing watts drops like Tuesday can be bummer, but it’s something I’ll start to plan for.
Today I upped my caffeine to help with my session and I got it done, it was definitely tougher than normal. I really challenged and pushed my mental toughness and I’m really proud of that.
I’m gonna try more carbs and caffeine for tomorrow and see what I can achieve. I’m looking forward to next week and seeing a bit of new life in my body again.
I find this stuff so so interesting! If you have any other books or sources i can read, I’d really appreciate it!
And thank you so much for the amazing chart! I’m gonna print it out and put it with my training books to refer to.


@Lacey_Rivette Well, my body threw me a curve ball and period is non existent and late. Not pregnant. I’m frustrated because I’m still under performing and I have team camp this weekend, so I’m anxious for my body to perform as I know it can.
I’ve worked so hard and have seen so much progress until last week and now I’m flat and legs are toast :sob:.

Hey @lindsay.marx , sorry to hear about the suboptimal performance you have been having. I think we have all been there and it is extremely frustrating, especially when you do not know the cause. There are a lot of factors that could be at play here and without having access to your TrainingPeaks, it is hard to say whether or not your training load is too heavy or not (or too heavy at the wrong times).

I do wonder though, have you lost a significant amount of weight recently, have you increased your training volume over the past few months/done so without increasing your calorie intake and have you had more stress than usual outside of training?

All of these could be playing a role in throwing off your body’s hormones and as a result, causing irregularities in your cycle and reduced performance.

Love this thread. Stacy Sims is a great resource and I highly recommend her book for specifics on tweaks for the time leading up to a period (Magnesium, aspirin and others) that can help with changes that we can experience. Sounds like I need to check out the app too!

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