The question: I went to the gym yesterday and now I have sore muscles. That means I had a great workout, right?
The answer: Not really. While working your muscles until they’re achy means you technically did tax your muscles, which helps them get stronger, it’s actually not beneficial work in the long run.
The reason? Pushing it to the max one day means you’re going to be too sore to hit the gym the next day, or the day after that. And that’s a serious issue, because consistency is the ultimate goal here. “It’s way more important to be able to exercise every day or every other day than to just kill it one day and not be able to move for four or five days after that,” explains Feldman.
In other words, it all comes down to the basic fact that moving more often is better for you than going all gung-ho for a bit, and then proceeding to kick it on the couch while muttering all sorts of FML, dear-muscles-I-hate-you lines. “You can't just say, 'I went hard a few days ago so I've done my time for the week,' because your muscles don't operate like that. They respond better when they’re being constantly worked—that prevents them from becoming weak and inactive,” Feldman continues.
So how can you tell when you’re about to overdo it? Well, if you start shaking or twitching during your reps, that’s a sure sign that you’re going to feel it big time tomorrow—so do yourself a favor and step awaaay from the weights. But even something as simple as feeling more tired halfway through your second set than you did at the end of the first means it’s time to stop, too.
Your sore-muscle Rx, then, is this: As soon as you start feeling noticeably exhausted, end the session. "That way, you’ll be able to come back the next day or the day after and therefore keep the muscles moving more consistently overall,” concludes Feldman.