What happens to my body when running?

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Runny noses, itches and needing the loo – the weird and wonderful side effects of running

Ever wondered ‘What happens to my body when running?’. There are so many benefits to be gained from running – in fact, we’ve got a whole article about them here . But while there’s plenty of positives that come from pounding the pavements, there are also a few strange side effects. From runny noses and mysterious itches to a sudden urge to ‘go’, we’re here to tell you what’s normal and why it happens.

Ready for a rundown of running weirdness? Let’s go!

Twitchy muscles

Ever get a sensation of spasming muscles post-run? If your legs start to twitch it could be a sign that you need to up your hydration levels. A tough run can cause you to lose electrolytes – which help your body to balance fluids and manage chemical reactions – quicker than you can replace them. Hydrating before and during your workout will help, or you could try a sports drink – there are so many different brands and types available that you’re bound to find one to suit. Just make sure you don’t wait until event day to try them out!

Mad itchiness

As you probably know, running pushes your heart and lungs into overtime to make sure all those working muscles have the oxygen-rich blood they need to do their job. But as the capillaries around your muscles full up with blood, it can stimulate your nerves – a signal that your brain can interpret as an itch. Although it can feel a little alarming, it’s nothing to worry about – and nothing a good scratch won’t solve. Ready, steady, itch!

Runny nose and eyes

It’s not just the capillaries around your muscles that are affected by running; the blood vessels in your eyes and nose can also end up overstimulated. And as those vessels dilate and then constrict, you might start to notice a steady drip, drip, drip. Exercise-induced rhinitis as it’s known can affect anyone – although if you suffer from allergies or live in an area with more air pollution, you might find that you’re more susceptible to suffering from The Snot.

Brain fog or dizziness

While most of the weird side effects of running are nothing to be concerned about, brain fog or dizziness is one to keep an eye on. It’s perfectly normal to feel light-headed after a long run – after all, your body has used up lots of glycogen and, if you’ve stopped suddenly, blood might be pooling in your lower limbs rather than heading up to your brain. The remedy? Flex your muscles, have a seat, refuel with a drink and a light snack. You’ll be back to full speed in no time.

Runner’s Trots

Picture the scene: you’re out for a run, you’re getting into your stride and feeling great…when you get an urge to go. And we don’t just mean a number 1, oh no. However embarrassing it might seem though, feeling a sudden need to go to the loo is perfectly normal. And, for those interested in the science, it’s most often down to a combination of your stomach being shaken about, blood rushing around your abdomen and perhaps even a few nerves – explaining why so many of us feel the urge on big race days. Let’s hope there’s a portaloo nearby, eh?

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