Woman stretching
Credit: Getty Images

You know that feeling you get when you hop out of bed the morning after a serious sweat session only to find that you can barely, well, walk? We've been there, and we know how brutal it can be. Here's a little encouragement for the days when it takes all of your effort not to crawl back under the covers with an ice pack: according to celebrity fitness trainer Lacey Stone, those aching muscles are actually a really good thing.

"The idea behind getting more physically fit is that you're doing exercises that test your limits, so during resistance training your basically tearing micro muscle fibers," says Stone. "When your muscle recovers, it’s going to be stronger and denser than before, which will create a leaner look if you have a healthy diet." Plus, those aches and pains also serve as a reminder of just how important it is to do regular physical activity. "Oftentimes people don’t workout often enough, in which case being sore is your body's way of telling you that you need to get back into a routine."

On the flip side, if you're super active, tender muscles can be a sign that you're working your body in new ways. "Being sore from doing different styles of workouts is also good because it means you are training your body in different ways, which helps because your body has a more well-rounded fitness routine. Yoga, spin, it all," advises Stone. "Never let your workouts get stale."

In fact, Stone suggest shaking up your activity on a day you're feeling sore rather than skipping a workout all together while you're muscles recover. "Just because you’re sore should not mean you’re not going to work out the next day, just do something different," she says. "If bootcamp made you ache, then do yoga. If yoga made you sore, go spinning. If spinning made you sore, go for a swim."

Watch: I'm Obsessed: Chantelle Sports Bras