Have you heard about avoiding high intensity exercises if you have polycystic ovary syndrome (PCOS)? The thought is that these activities increase cortisol levels, which can negatively affect hormone balance. In fact, there is a lot of online discussion these days about modifying your movement depending on where you are in your menstrual cycle, for a variety of different hormonal concerns, including PCOS. While it makes sense to tune into your body, and honor what you need, sometimes this conversation is filled with misinformation and can become another barrier to regular movement. So, I want to take some time to talk about recent research into the benefits of high intensity interval training (HIIT) for those with PCOS.

What is PCOS?

PCOS is a common hormonal disorder that can cause irregular periods resulting in fertility difficulty, elevated androgens (ex. testosterone) and associated symptoms (ex. acne, hair growth on the face), and cardiometabolic concerns (ex. Insulin resistance, diabetes, elevated cholesterol). It is diagnosed when people meet two of the three following criteria:

1. Irregular or absent menstrual cycle

2. Elevated androgens on blood work, or physical signs of elevated androgens (ex. Acne, hirsutism)

3. Polycystic ovaries found on pelvic ultrasound

What is HIIT?

HIIT is a type of exercise that involves short bursts (ex. 30-60 seconds) of high intensity exercise, followed by a rest or low intensity exercise interval. This pattern is repeated for a few rounds. In the research, HIIT was often done 3 times per week, and included exercises like outdoor running/walking, running on the treadmill and using the stationary bike.

Exercise & PCOS

There has been a lot of positive research on the benefits of exercise for PCOS. At the same time, online discussions can feed into fear about the potential harms of high intensity cardio in particular for those with PCOS. Many people already struggle with prioritizing regular movement  for a variety of reasons, so it is important to not create more barriers to exercise by sharing inaccurate information.

HIIT (ex. Sprinting intervals on a stationary bike) and moderate intensity continuous training (MICT; ex. Continuous pedaling on a stationary bike) helped to improve physical fitness and lower testosterone in those with PCOS.[1] In another study, running & walking HIIT improved many parameters of PCOS, and actually lowered cortisol levels after 8 weeks of training.[2] This is contrary to the narrative that strenuous exercise raises cortisol for those with PCOS. Yet another study compared HIIT to moderate intensity exercise (ie. sprints on a stationary bike versus continuous peddling) in those with PCOS and found a greater improvement in menstrual cycle regularity in the HIIT group.[3] The big takeaway from all of these studies is that high intensity exercise is helpful for PCOS, and you don’t have to avoid cardio if you have PCOS.

Don’t let people scare you from doing more strenuous exercise, especially if that is what you enjoy. If you are new to exercise, start by exploring what you like or are curious about. If you have PCOS, remember that HIIT was accomplished through many different types of exercise in these studies, and benefits were often noticed within a few months of regular movement.

While this article is about exercise for PCOS in particular, I think it is important for you to understand that you can likely safely continue whatever movement you enjoy at any time of your cycle, even if it is more strenuous. In fact, it is likely beneficial. At the same time, it is OK to modify your routine to better support what you need when experiencing period pain, premenstrual syndrome (PMS), recovering from period loss due to hypothalamic amenorrhea (HA) etc. If you are concerned about your period, and whether you should modify your activity, schedule an appointment to get the individualized support you deserve.

In health and happiness,

Dr. Chelsea Cole, ND | Naturopath Victoria BC

References:

[1] Philbois S. et al. Cardiovascular autonomic modulation differences between moderate-intensity continuous and high-intensity interval aerobic training in women with PCOS: A randomized trial. Front. Endocrinol. (2022) 13:1024844.

[2] Mohammadi, S. et at. Effects of eight-week high-intensity interval training on some metabolic, hormonal, and cardiovascular indices in women with PCOS: a randomized control trial. BMC Sports Science, Medicine and Rehabilitation (2023) 15:47

[3] Patten R. K., et al. High-intensity training elicits greater improvements in cardio-metabolic and reproductive outcomes than moderate-intensity training in women with polycystic ovary syndrome: a randomized clinical trial, Human Reproduction, Volume 37, Issue 5, May 2022, Pages 1018–1029