Ask the Celeb Trainer: Are Sore Muscles a Sign of a Good Workout?

If your New Year's resolution to get in shape stalled out fast, you might be panicking right about now since bikini season is right around the bend. Making up for lost time with an aggressive workout routine will likely leave you sore, but begging for more once you see your thighs trim down and take form.

That burn you feel 24 to 48 hours after an intense workout is called delayed onset muscle soreness (DOMS), and it's enough to make you want to put down the Kettlebell and pick up a cocktail. But press on! We talked to fitness and nutrition expert Harley Pasternak, M.Sc., author of The 5-Factor World Diet, and trainer to celebrities like Lady Gaga, Megan Fox, and Halle Berry, about why (some) pain is good.

"The idea behind resistance training is that you're basically tearing something and creating a micro trauma in the muscle," Pasternak says. "When the muscle recovers, it's going to recover stronger and denser than it was before." So that soreness you feel the day after an upper-body workout-when you're hauling groceries into your car and you can hardly lift your arms-is good.

Just make sure what you're suffering from is DOMS and not an injury. "A good way to tell the difference is if the pain is bilateral," Pasternak says. Having one very sore shoulder after you've worked both shoulders could spell injury.

Related: Get Strong Sexy Arms in 30 Days

If you feel normal soreness in a muscle, ligament, or tendon, it's DOMS and you can continue working out around it, Pasternak says. In the case of arms and shoulders, you can work your quads, abs, or glutes and then move back to your upper body in a few days.

To avoid feeling the pain of DOMS the next time around, Pasternak suggests starting your exercise routine slow. "Increase your resistance gradually so that your muscles adapt to your new workout plan." He also shared his top four tips to relieve (or avoid) sore muscles, so pain will never be an excuse to skip your workout again-and that's a good thing!

Harley Pasternak Top 4 Tips to Reducing DOMS
1. Warm Up. "Increase body temperature to help prepare your muscles for the shock of an intense workout," Pasternak says.

2. Stay Hydrated. "A lack of electrolytes can make muscles sore," Pasternak says, who recommends drinking easily digested fluids so you can power up and avoid an upset stomach. "Look for beverages with no protein or stimulants like Powerade Zero." (And steer clear of these 10 worst drinks for your body!)

3. Ice Sore Muscles. "Have a cold pack handy to reduce pain and inflammation," Pasternak says. ACE has an Instant Cold Compress that's super convenient. "Give it a twist and you've got instant ice."

4. Do Cardio. "A cardio workout increases blood flow and acts as a filter system. It brings nutrients like oxygen, protein, and iron to the muscles that you've been training and helps them recover faster. As the blood leaves the muscles, it takes some of the metabolic bi-products with it (like carbon dioxide and lactic acid) that may be causing DOMS."

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