Time to train aside, another huge barrier to running and racing is our periods. There’s nothing like the threat of coming on just before a marathon to double the mental load. On the other hand, the idea of losing your cycle to overtraining is a terrifying one. Power doesn’t just train for marathons – she runs several marathons back-to-back. How does she manage to look after her cycle when tackling so many miles?

“The most important thing is tracking,” she says. “I look at everything. I live my life by my heart rate variability (HRV – tells you about fitness and recovery) and heart rate. Both of those play into your hormones in terms of your body’s stress and functioning. I really value my period and the knowledge it gives me as to whether I’m in balance. If I’m training more than usual, my period tends to get a bit longer. But I also mess around with my cycle for races – I’ll change my cycle. I use a progesterone role.”

Because she’s so rigorous about tracking her period, Power says she knows that she needs to eat more in the luteal phase. “This is fine for a four-hour run, but often when doing a long ultra, how much you’re able to eat and drink becomes a limiting factor. I don’t want to run a race in the second half of my cycle because I don’t want to try to eat and drink more. And the first three days of my period are really heavy, so I don’t want to run on those days. I’d happily do a marathon then but I don’t want to be bothered with changing tampons and cups every few hours.”

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