6 Possible Reasons Why You Experience Muscle Twitching After a Workout

At the end of your workout, you’re sweaty, you’re thirsty… and your muscles are twitching? If your muscles feel like they’re moving on their own after getting active, there may be a good reason why. In fact, it may offer insight into your lifestyle or exercise habits and motivate you to make a healthy routine shift.

Read on to learn about what muscle twitches are, whether or not they’re normal, and if there’s anything you can do to calm them down in the moment—plus prevent them in the future.

What Are Muscle Twitches?

When your muscles are jumping, what’s really going on? “A muscle twitch is a short contraction of the muscle,” explains Jenna Bendio, DPT, a physical therapist and certified athletic trainer with Peak Physical Therapy. 

Technically, muscle twitches are known as fasciculations, which are rapid, involuntary muscle twitches that aren’t strong enough to move your arms or legs, yet are still easy to feel, as defined by Stephen McGee, MD, an internal medicine physician. (One commonly felt muscle twitch is in the eyelid, which you might notice if you were up late last night and are grappling with fatigue now.)

Your peripheral nervous system (the part of your nervous system that's outside of the brain and spinal cord) powers the muscles. As these nerves activate, you might feel a twitch, which you may or may not be able to see happen under your skin, explains Leada Malek, DPT, a board-certified sports physical therapist. 

What’s the Difference Between Muscle Twitches, Spasms, and Cramps?

While muscle twitches, muscle spasms, and muscle cramps might understandably sound like the same thing, they’re all a bit different. As mentioned, muscle twitching is when your muscles involuntarily twitch. You may experience muscle twitching after exercise in one of the muscle groups you’ve just worked hard in said exercise or sport, such as your quads or calves.

Meanwhile, muscle spasms are full muscle contractions that can be painful. Muscle spasms are often referred to as muscle cramps, but cramps can last longer. Like muscle twitches, cramps and spasms are unexpected and involuntary.

What Causes Muscle Twitching?

Muscle twitches are incredibly common: About 70 percent of healthy people experience them at some point, according to the Cleveland Clinic. 

That said, you might be more prone to muscle twitches due to a specific lifestyle or exercise habit. “Muscle twitching provides some interesting feedback for someone who is improving their body awareness,” Malek says. If you’re wondering why your muscles twitch after working out, here’s what might be triggering those micro movements:

New or Difficult Exercise

Are you trying a new exercise that’s particularly difficult? “If it’s something new and hard for the body to figure out, your brain may essentially tell your muscles to jump in,” Malek says. Plus, that ramped-up nervous system could lead to a twitch. “Sometimes you’ll see twitching last only during the exercise. One example is while holding a leg press, you look down at your quad and see all this stuff happening in the muscle,” she explains. This twitch may last only momentarily, but go away when you stop moving.

Too Much Exercise

Although muscle twitching can be a rather random occurrence, another possible cause is overtraining. “Doing too much exercise can often lead to a twitching sensation,” Bendio says. In fact, muscle twitching can be one indication of where your threshold is. So, if your muscles are twitching after a workout, you may want to continue to stay at that level until you build strength or stamina before moving on in duration, speed, or weight. 

And by the way, this muscle twitching can happen whether you’re performing a one-rep max deadlift (where you lift as heavy of a weight as you can for one rep) or racing in a marathon, she says. In both scenarios, you’re pushing yourself to do your best, which requires working your muscles extra hard—leading to some potential twitches post-workout.

Fatigue

How have you been sleeping lately? Sleep is important for proper neuromuscular function. If you’ve been skimping on shut-eye lately, muscle twitching after a workout may be your signal to start prioritizing better sleep hygiene habits and a solid snooze routine.  

Dehydration

Your hydration status affects your electrolyte balance (such as how much sodium you have in your body), and electrolytes are key for proper muscle contraction. So, when you’re dehydrated, your muscles might twitch as a result. To know if you’re properly hydrated, Bendio suggests using the pee test: If your urine is a pale yellow color, you’re hydrated. Bright yellow or darker? Drink up.

Caffeine

Caffeine is a stimulant that affects your nervous system, and drinking too much of it may also contribute to muscle twitches, Bendio says. The U.S. Food & Drug Administration recommends sticking to 400 milligrams of caffeine per day, or about four or five cups of coffee. Other tell-tale symptoms of consuming too much caffeine include jitters, anxiousness, a fast heart rate, and insomnia. Keep in mind that a lack of sleep can cause fatigue and may lead you to reach for more caffeinated beverages, creating a cycle that’s tough to escape.

Stress and Anxiety

When you’re stressed or anxious, there’s a tendency to tense up (or contract) your muscles. This makes them more prone to twitching or spasming, Bendio says. Stress triggers other changes in your body and lifestyle as well, like altering your breathing (making it faster and shallower) and possibly affecting your sleep habits. 

How to Stop Muscle Twitching

Muscle twitching after a workout will likely go away on its own. “If you worked out and your muscles twitched, I wouldn’t worry too much about it,” Malek says. “Go about your routine, and it will go away eventually.”

That said, there are some action items you can take to help stop muscle twitching after a workout:

If your muscle is in a full spasm (rather than just a twitch), you should take a different course of action. First, stop and take a few deep breaths to calm your nervous system, followed by light movement of the muscle. Then stand up, walk, and finally, stop to stretch, Bendio says. (“If you try to go straight into stretching the muscle during a spasm, it will just tighten up again,” she explains.) 

Moving forward, it’s also important to make sure you’re warming up with some dynamic stretching and/or a light version of the activity ahead (like slow jogging if you’re running) in order to prep the muscle for the work ahead, Bendio adds. And as always, reach out to your doctor or physical therapist with any questions or concerns about muscle twitching after exercise.

Is it Normal for Muscles to Twitch After Exercise?

The good news is that most times, muscle twitches after a workout are benign. In fact, “many people will experience them,” Malek says. 

If you’re experiencing muscle twitches after a workout, there are a couple approaches you can take. The first approach is pretty simple: Notice the muscle twitch happening, wait for it to go away, and then move on with your day, as long as your muscles aren’t twitching all the time.

Another approach, especially if muscle twitching is a new experience or happening fairly regularly (but not bothersome or affecting your movements—more on that below), then you can use it to try and learn something about your body and mind. 

“I wouldn’t worry too much, but take it as a little sign that says your nervous system is really running right now,” Malek says. There could be a direct and identifiable cause—for instance, you’re in a time of deep stress right now—or it could be for no reason at all. 

That said, Malek says that if you have persistent muscle twitching along with changes in muscle function, such as weakness, it’s time to make an appointment with your doctor. Nervous system conditions such as amyotrophic lateral sclerosis (ALS) or neuropathy can also cause muscle twitching, according to the Icahn School of Medicine at Mount Sinai.

The Takeaway 

Muscle twitching is a fasciculation of the muscle, or a minor, involuntary movement in the muscle. Most often, it’s benign and you don't need to do anything to treat a twitch—notice the funky sensation, then let it go away. However, in certain instances, muscle twitching after a workout may be telling you something about your exercise routine (such as you’re overtraining without adequate recovery) or lifestyle habits (such as you’re not getting enough sleep or you're in a period of stress overload). Consider the muscle twitching prevention tips listed above, and as always, consult with your doctor if the muscle twitching is bothering you or isn’t stopping.

This content is for informational and educational purposes only and does not constitute individualized advice. It is not intended to replace professional medical evaluation, diagnosis, or treatment. Seek the advice of your physician for questions you may have regarding your health or a medical condition. If you are having a medical emergency, call your physician or 911 immediately.