Why a New Exercise Routine Gives You Cramps, Itches, and Side Stitches

You know you should probably exercise, but starting a new workout habit is just so hard. It's tough enough to get up early to go to the gym without enduring painful side aches and uncomfortable itching through your workout. Why does a new workout routine feel so awful? Science doesn't have all the answers, but it does have one piece of good news: The more you exercise, the less uncomfortable you'll feel.

Why Do My Muscles Cramp?

As long as humans have had muscles, they've had cramps, so it may surprise you to know that scientists still can't really explain why muscles cramp. Theories abound: not drinking enough water, not consuming enough electrolytes, not stretching, and hot weather have all been blamed for that fearsome charley horse. But none of those reasons are supported by scientific evidence. Cramping athletes don't show any difference in electrolyte or hydration levels than non-cramping athletes. While stretching (or more specifically, contracting the opposite muscle) helps relieve cramps, there's no evidence that it prevents them from happening.

What's most likely is that when muscles fatigue, their reflexes start to misfire, causing an uncontrolled contraction. That's not as easy to prevent as something like dehydration, but there are some things you can do to help. Pace yourself, and rest when you need to. Research shows that massage and light stretching can help when a cramp strikes. A study also suggests that pickle juice can help relieve cramps — not because of the electrolytes, but just because of the taste, strangely. That means that anything that tastes comparably salty and acidic would probably do the same thing.

But yet again, exercising more is a good fix. The fitter you get, the longer it takes your muscles to fatigue.

Why Do I Get Side Aches?

Most experts agree that a side ache, or side stitch, is just a cramp in your diaphragm, the parachute-shaped muscle that helps your lungs fill with air. It may be that constant bouncing, like when you run or ride a horse, can cause spasms in your diaphragm. But another hypothesis is that it's caused by irritation of a membrane called the parietal peritoneum, which lines your abdominal and pelvic cavity. The idea is that excessive movement, a full belly after a large meal, or slouching when you're fatigued can all irritate this membrane. In that case, dehydration could play a role, since that could lead there to be less fluid in the layers of the peritoneum, and therefore more irritation. Slowing down and regulating your breathing can also help.

In this case, experience only helps a little — even elite athletes get side aches from time to time. They just become better equipped to handle the pain. The best way to figure out how to get past a side stitch may just be trial and error. You just have to figure out what works for you.

Why Do My Legs Itch?

On your first run in a few months (or years, we won't judge), you may feel an unbearable itching in your thighs, chest, or abdomen. There are a few possible causes for that sensation, but the most likely culprit is blood flow. As blood rushes to fill previously idle capillaries and arteries, they expand. That stimulates the surrounding nerve cells, which transmit signals that your brain interprets as itching. That sensation should subside as you build up stamina over time.

There are a few other reasons exercise might be making you itchy, however. Sometimes friction from your clothes or heat from physical activity can make your body release histamines, the same things that cause rashes and runny noses during allergy season. Antihistamines like Benadryl can help with that. Least likely, but most serious, is a condition called exercise-induced urticaria. You know that when you see it: Red bumps crop up all over your skin. The worst cases can even lead to a life-threatening allergic reaction, so you may want to consult a doctor if you suspect you have this condition.

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Written by Ashley Hamer September 15, 2017

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