If you don't feel particularly fit during menstruation, then listen to your body by scaling back on training or foregoing it altogether. — dpa
On some days your runs fly by easily, on others every kilometre is a struggle.
Anyone who regularly does sport knows that performance has its ups and downs.
For women of child-bearing age, the menstrual cycle factors into the fluctuations.
How exactly?
And how can they use this knowledge to better plan their sport activities?
Let it be noted at the outset that still little is known about the menstrual cycle’s impact on sport performance, training effects and injury risk.
But an increasing number of studies suggest that even recreational female athletes can benefit by gearing their training to their body’s needs.
There are no tips that work for everyone though.
”Everything having to do with the female menstrual cycle is very individual,” says biochemist and endocrinologist Dr Patrick Diel, a professor at the Cologne-based German Sport University (DSHS).
“In addition, the database is still too thin to allow evidence-based assertions on the subject of sport training and menstrual cycle.”
This is due in part to the myriad factors affecting the cycle, which can vary from woman to woman. Dr Petra Platen, a sports medicine specialist at Ruhr University in Bochum, Germany, gives a few examples:
“Some women have bleeding without ovulating. Others take the pill or use another contraceptive. Hormone fluctuations during the menstrual cycle vary widely as well.
”What’s more, sports disciplines and training intensities can be very different from each other, making generalisations difficult.
”On the first days of their period – the onset of bleeding, in other words – most women are typically less keen on sport, finding it harder to rouse themselves," remarks Dr Platen.
Studies also show, according to her, that women’s performance capability – with respect to strength as well as endurance and speed – is in fact somewhat lower for one to three days after bleeding begins compared with other phases of their menstrual cycle.
”How they feel physically can fluctuate during the course of their cycle too,” Dr Platen says.
They may experience breast pain, an achy lower abdomen and/or heaviness in their legs, which can blunt their keenness to do sport.
Blame it on the hormones
Despite subjective discomfort, their objective performance may remain unaffected though.
Most women feel fittest toward the end of the first half of their menstrual cycle, as ovulation approaches.
“Oestrogen levels are elevated in this phase,” notes Dr Platen.
Oestrogen, the primary “female” hormone, is an anabolic hormone, and as such plays a role in muscle building.
Levels of the principally male sex hormones are also somewhat higher in women around the time of ovulation.
Citing a study of female recreational athletes in which she participated, Dr Platen says there are indications that strength training is more effective in the first half of the menstrual cycle – known as the follicular phase – and around ovulation than in the second half.
The rise of oestrogen levels around ovulation doesn’t only bring advantages. In one study, women who had sustained cruciate ligament damage were asked when their injury occurred.
For most of them, it was shortly before or around ovulation.
To put it simply, Dr Diel explains, oestrogen and progesterone, a hormone that supports menstruation, cause a loosening of body tissues.
”Ligaments, including in the knees, become looser, meaning joints are less stable and the knees buckle more easily, for example while running,” he says.
This occurs in the second half of the menstrual cycle, the luteal phase, which starts when an egg begins its journey to the uterus.
This is all circumstantial evidence, however, not hard facts, and women can be very different from each other.
How can the scientific findings, such as they are, be applied in practice?
Although fact-based recommendations can hardly be made, a few pointers are possible nonetheless.
”With regards to performance capability, I’d advise women to engage in sports in every phase of the menstrual cycle so long as they want to and feel fit,” Dr Diel says.
Those who do strength training should do it around ovulation, which could produce better results.
”And women who know they may be more susceptible to ligament or tendon injuries, or who have had a previous such injury, shouldn’t necessarily do running training in the time just prior to their period,” he adds.
In phases when female athletes don’t feel particularly fit, they should listen to their body – in other words, not train as hard as usual or not train altogether.
”If you’re aware of these motivation swings, you can acknowledge them without getting upset,” says Dr Platen.
“Then you’ll also know that in a few days you’ll be full of energy again and keen on sport.
”So at the end of the day it’s about understanding your body better and organising your training accordingly.
"First and foremost, it’s important that women have a menstrual cycle at all, and that it occurs as regularly as possible and with ovulation,” Dr Platen says.
The absence of menstrual periods when no gynaecological disorders are present is definitely a sign of insufficient calorie intake, in which case female athletes should either eat more or train less – or both.
”A normal menstrual cycle is important for every woman’s health,” Dr Platen says, so female athletes should be sure to take care of it. – dpa
