It’s common for even the fittest of women to hold back on their exercise routine when that time of the month rolls around.
Giving into chocolate cravings and binge-watching Netflix series seems like a much better option than a sweat session.
But it turns out, when you have your period is actually a great time of the month to work-out. Your pain tolerance is higher, you take longer to get tired and you recover faster.
Why? Exercise physiologist and human performance researcher Dr Stacy Sims explained, your hormones are “most like a guy” during this stage.
In an interview with The Sydney Morning Herald, Dr Sims explained that at this time of our menstrual cycle, our hormone levels drop and this affects everything from how cool you feel to how easily you access energy stores.
"Pain tolerance is increased; time to fatigue is increased; she has a lower core temperature and greater plasma volume, so she can sweat more and stay cool longer, and from a metabolic state, a woman's body can tap into more carbohydrate stores and recover faster, as compared to the high hormone phase that leads into her period," Dr Sims explained.
So how exactly do you make the most of this, ahem, period?
Dr Sims said that this is the perfect time to be heading to the slightly intimidating-sounding HIIT classes at the gym or to try for your personal best time on the treadmill or at a running event.
Our favourite celebrities work out - and they aren't afraid to brag about it with the odd gym selfie or two. (Post continues after gallery.)
"It's during this low-hormone phase that women should aim to hit high-intensity training sessions hard, try for PRs in power and speed activities, and optimise recovery through nutrition," she said.
However, personal trainer Nardia Norman added that pushing yourself to exercise intensely when you don't feel up to it, isn't a good idea.
"Women are already hard enough on themselves," Norman said.