As most of my friends know, one of my favorite phrases is "If you're not sore the next day, you didn't go hard enough." When I was younger, my dad used to ask me the day after a long weekend of softball games if I was sore. If the I said yes, he would say, "Good, that just means you played hard." If the answer was no, his reply would always be, "Well, you must not have played hard enough." Now, you might not have ever heard my phrase before, but I can almost guarantee that at one point in your life you've heard the phrases "Pain is weakness leaving the body" or "Whatever doesn't kill you makes you stronger." I am here to completely discredit both of those phrases.
I like being sore. Soreness is a common result of working out, and it's a sign you're building muscle. If you work out at the same pace day after day without being sore, you really aren't doing anything productive. When your muscles burn during a workout, that is a sign that the little bitty fibers that make up your muscles are stretching and tearing, and that is what causes the next-day soreness. That sounds bad, right? Well it's not! Whenever these fibers tear, they come back stronger and that's how you build muscles (but you need to give your muscles 24-48 hours to do this repair). Now, you might've heard that lactic acid is the main cause of soreness (like I've heard before), but that's not the case. However, lactic acid does have an effect on the way you feel the next day. Lactic acid is a waste product from energy conversion (You can read about it here) that will build up in your muscles, and if you don't give your body a chance to rid it, it will become painful! The best way to keep from getting a build up is to make sure you cool down after your workout. I had a severe build up my senior year in high school, and trust me, you don't want this to happen to you!
So, moving on to discrediting those phrases. There is a big, big difference between soreness and pain (if you're just starting out soreness might feel like pain but I promise it's not). Now, pain is not weakness leaving the body - pain is your body's way of telling you something is wrong. We are given this sense so that we will listen to it! And, though "what doensn't kill you will only make you stronger" might hold true in a psychological or emotional sense, it definitely doesn't in a physiological sense. If you tear your ACL, it will not kill you (though it might make you wish you were dead), and it will definitely won't make you stronger.
So, to wrap up this discussion - soreness is good, pain is bad. If you're sore, give that muscle group a good 24-48 hours to repair those little tears, then work those (now bigger and stronger) muscles out again! If you're in pain, stop exercising, give yourself a good, long break and go see a doctor. Working out while you're in pain is not only a bad idea, but it could make what would have been a quick-healing injury something serious. So - listen to your body!
Tomorrow, I'm going to try to talk about listening to your body in regards to your diet so make sure to check back in! Thanks for reading y'all, and I hope you have a great rest of the day!