Here's a new term for you to throw around in the weight room: Muscle fever. Though you may not have heard this particular name for it, we're betting you've definitely experienced it after you hit it hard at the gym or went extra-long on your last run or ride. You felt like a beast in the moment, but now simply grabbing things off high shelves or going downstairs has you grimacing. Less awesome. What you’re experiencing is muscle fever, or as it’s known more technically, delayed onset muscle soreness (DOMS). “The jury’s still out as to exactly why it happens,” says Lance Dalleck, Ph.D., assistant professor of exercise science at Western State Colorado University. “But the leading candidate is that excessive eccentric contraction causes muscle damage, inflammation, and stress that trigger the pain receptors.” Eccentric muscle action refers to movements that have you releasing load, such as the lowering portion of a bench press, the release portion of a row, the action of starting and stopping a lot (such as in intervals), or even a lot of running downhill. “Most people who’ve done some activity will know after what workouts they can expect it,” Dalleck says.
Muscle fever isn’t necessarily as bad as it sounds or an indication that you totally overdid it (with some exceptions.) “It’s a sign that your body is on the move to improvements in strength,” says Michele Olson, Ph.D., professor at Auburn University Montgomery. “You overloaded the muscles, which is important for your body to adapt upwards and get fitter and stronger.”
That said, muscle fever really doesn’t feel so hot (at least figuratively.) Here’s what you can do to bring it down.