It might be painful, but easy-paced running when you're sore is one of the best things you can do to recover — as long as you're not injured. That soreness is caused by micro-tears in your muscles, and doing an easy run as a recovery increases the circulation, reducing the soreness.
However, if what you're considering "soreness" is more like a sharp pain, then it's time to take a time-out and possibly see a physician.
Read More: How to Ease Muscle Soreness After a Workout
Sore but Safe
The type of soreness you typically experience after a hard workout is known as delayed onset muscle soreness, or DOMS. It's caused by small tears in your muscle fibers, typically occurring about 24 to 48 hours after you do a new or more intense workout. It won't damage you further if you do an easy run, despite the soreness.
There are a few things you can do to reduce DOMS, such as taking an anti-inflammatory, icing the sore muscles — up to 20 minutes at a time, around three times a day — and massage, whether going to a professional masseuse or using a foam roller to soothe the aches.
Just because it's not harmful to run when you're sore doesn't mean you have to go out and do sprints. It's perfectly OK to modify your running workout to do a flatter course, slower pace or less mileage.
Take a Break
Sometimes it's hard to differentiate between painful soreness and an actual injury. A few ways to know if it's an injury:
- If the pain shows up in less than 24 hours, it's probably not DOMS.
- If the pain is sharp rather than sore, it's probably injured.
- If one leg, foot or knee hurts more than the other one, be cautious.
Err on the side of caution. If you have pain that could be an overuse injury, take a couple days off and let it heal up. If you do a warm-up later in the week, and it still hurts, then see a doctor. If the pain lessens as your muscles warm, then you're probably just a little sore.
At the end of the run, spend as much time as you can stretching. The more stretching you do, the better you'll recover and the less sore you'll be. When you wake up in the morning, even if you're feeling sore, do a few shoulder rolls, quad stretches and other dynamic movements to get your blood circulating.
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