Why Working Out is Harder Before Your Period (and What to Do About It)

Feel more sluggish in your workouts the week before your period? It’s not just you. It’s biological!

The changes across your menstrual cycle affect the way your body responds to workouts.

Quick biology reminder: the “follicular phase” describes the part of your cycle that’s before you ovulate (release an egg). The “luteal phase” describes the part of your cycle that’s after you ovulate.

You likely feel quite a difference in energy and mood between those two phases!

Progesterone is the luteal phase’s dominant hormone, and it’s a key factor when looking at your workouts. If you boil it down to evolution, your body is trying to protect itself and keep you calm and rested just in case you could possibly be pregnant— even if you’re definitely not pregnant.

So, the presence of progesterone chills you out energy-wise, and makes you seek out relaxation and extra sleep. That response rolls over into your fitness plans and has the following effects.

Luteal phase effects on exercise:

• The rise in progesterone elevates body temperature, and plasma volume drops.

• Your blood is thicker (due to lower plasma volume), so oxygen takes longer to travel among your muscles.

• Metabolism is higher (so you eat more during this phase).

• Energy dips due to the drop from pre-ovulatory levels of testosterone and estrogen.

• It’s harder to burn carbs (so low-intensity endurance is fine, but high-intensity workouts require eating more carbs beforehand).

• Heart rate and respiratory rate increase.

What all that might feel like:

• You feel hotter, but it’s harder to sweat and cool off.

• You feel hungrier before/after working out.

• You struggle to hit the fast paces or lift the same weight as you could in the past weeks.

• Breathing is more labored.

• It takes longer to recover between sets/repeats.

• It takes longer to recover between workouts.

• Motivation decreases.

How you can deal:

• Prioritize protein within 30 minutes after exercise to prevent muscle breakdown.

• You might need to eat a bigger pre-workout snack than usual. (Even if you work out right after waking up, at least eat something small first.)

• Do lower-intensity workouts leading up to your period (e.g. long runs are fine, but high-intensity interval training is counterproductive).

• Modify your training plans as needed. Plan your hardest workouts for the follicular phase (before ovulation) and keep recovery and taper weeks in the luteal phase (after ovulation). Your training cut-back week can perfectly fit with the last week of your menstrual cycle.

• Take a sodium-based electrolyte drink/tablet before exercising.

• Make sure you recover fully between workouts with proper rest and refueling.

• Ensure you eat enough healthy fat, vitamins and magnesium.

• Schedule exercise with a friend when motivation is low but you feel like moving.

• Get a handle on PMS symptoms (which might make exercise feel worse).

• TRACK YOUR CYCLES so you can predict when these changes will occur!

The good news:

• Your cycle keeps your body balanced by ensuring you get a variety of movement and workouts over the weeks and months.

• By loading up your follicular phase calendar with your tough workouts, you’ll get fitter.

• By using your luteal phase as a chance to focus on lower impact endurance, injury rehabilitation and recovery, you’ll ensure your body is healthy and ready to go next cycle. It’s intuitive and strategic!