Have you ever finished an exhausting workout and noticed that your leg or arm is twitching and won’t seem to stop? You wait and wait and it’s still there! At that point, you become concerned. Could it be a sign of something serious?
You might be surprised to learn that muscle twitches after exercise are common and tend to show up after a long or grueling workout. The scientific term for them is benign fasciculations, another name for a twitchy muscle. Most often, these twitches are in the arms, hands, feet, or legs, although they can affect other muscles too.
Benign fasciculations are an annoyance, but they strike fear in some people who worry it’s a sign they have a serious neurological problem, like multiple sclerosis or ALS (Lou Gehrig’s disease) Although people with both conditions can have fasciculations, it’s usually not the first or only symptom they have.
For example, people with ALS may have twitches, but they usually have significant muscle weakness too and may have difficulty grasping items and holding them in their hands. ALS sufferers may also have problems talking or swallowing. Usually, the twitches that people with ALS experience get worse when moving the muscle. With benign fasciculations, movement usually stops the twitching.
Benign Fasciculations Are More Common in Athletes
Fasciculations can occur in healthy people and exercise is a powerful trigger. In one study, researchers used ultrasound to look at fasciculations in 50 athletes (male and female) after they played handball for 90 minute or ran 5,000 meters.
Their findings? All the men and women in this group had fasciculations in their thighs after working out. Twitching was four times more common in the runners than the handball players. The researchers concluded fasciculations can occur in healthy individuals after exercise and occur in the muscles that worked the hardest, usually the legs.
What Causes Muscle Twitches After Exercise?
When you exercise, your brain signals your muscles to contract. If you exercise too long or too hard, the nerves that trigger the muscles can become overly excitable and keep sending messages to contract. The twitches are repeated muscle contractions occurring at a rapid pace. If you look closely at the affected muscle, you can see it moving rhythmically.
There’s another type of contraction called a fibrillation where the muscle twitches, but you can’t see it. Stress, particularly anxiety, and too much caffeine are other triggers for fasciculations because they overexcite the nervous system and send it into overdrive.
Another common type of fasciculation is eyelid twitches, where the corner of the eyelid repeatedly contracts. You may have experienced one after staring at a computer monitor all day or after drinking too much coffee. They usually stick around for a few days and then disappear. Fatigue and allergies can also cause annoying eyelid fasciculations. Like fasciculations brought on by exercise, eyelid fasciculations are usually benign and disappear on their own.
Are There Ways to Prevent Muscle Twitches Triggered By Exercise?
Since fasciculations are more common when you overfatigue your muscles, scaling back on the intensity or length of your workouts will help your nervous system calm down. There’s also some evidence that dehydration and electrolytes imbalances are a factor. Fasciculations are more common during the summer months when people sweat a lot and lose more water and electrolytes.
Remember to hydrate before, during, and after workouts. A few hours before a sweat session, drink 20 ounces of water, and keep a water bottle close by to sip on throughout your workout. Afterward, weigh yourself and rehydrate with at least 16 ounces of water for every pound you’re down.
If you’re exercising for longer than an hour, an electrolyte-rich beverage is a better choice. If you take certain medications, like a diuretic for blood pressure control, you’re at greater risk of dehydration and electrolyte imbalances. Other medications that can trigger fasciculations include corticosteroids, like prednisone and hormone replacement therapy.
Watch Out for Caffeine!
Also, cut back on caffeine and make sure you’re getting at least 7 hours of sleep per night and have ways to manage stress. Remember, caffeine isn’t just in coffee and many people load up on less obvious sources of caffeine such as tea, energy drinks, soft drinks, cocoa, and analgesic medications that contain caffeine.
Although there isn’t a study proving it, some experts believe doing dynamic stretches before working out may prevent those pesky twitches. It’s important to warm up a cold muscle before hitting it hard, however there’s no solid proof that stretching prevents fasciculations. Also, make sure you aren’t training the same muscles intensely two days in a row. Give the muscle you hit hard at least 48 hours of rest before working them hard again.
Make sure you’re eating a nutritionally balanced diet and getting enough sunlight. Deficiency of vitamin D and some B-vitamins can trigger muscle twitches if severe. If you eat a vegetarian or vegan diet, you’re at greater risk of vitamin B12 deficiency. Vitamin B12 deficiency can cause other neurological symptoms too, including numbness in the hands and feet, tingling, weakness, brain fog, and problems with balance.
When to See a Doctor
If muscle twitches persist for more than a few days and if they keep coming back, see your physician. Also, you should see your physician if you have muscle weakness, headaches, balance problems, dizziness, difficulty swallowing, or visual problems.
The Bottom Line
Most of the time, muscle twitches after exercise are benign and go away on their own. They’re usually nothing to worry about unless they become a frequent problem or occur with other symptoms, like muscle weakness, but if they don’t go away in a few days, it’s best to get an evaluation. Now you have a better idea of what causes them.
References:
- Czell D, Goldman B, Weber M. Distribution Of fasciculations in healthy adults after exercise: An ultrasound study. Muscle Nerve. 2016 Jun;54(1):132-5. doi: 10.1002/mus.25034. Epub 2016 May 19. PMID: 26789013.
- “Fasciculation – an overview | ScienceDirect Topics.” https://www.sciencedirect.com/topics/neuroscience/fasciculation.
- “Benign Fasciculation Syndrome: Symptoms and Treatment.” 22 Jun. 2017, https://www.healthline.com/health/benign-fasciculation-syndrome.
- “Benign fasciculation syndrome: Causes and symptoms.” 21 Dec. 2017, https://www.medicalnewstoday.com/articles/320388.
- “What is Benign Fasciculation Syndrome? Causes, Symptoms ….” https://benignfasciculationsyndrome.org/.
- “Another Perspective on Fasciculations: When is it not ….” 05 Aug. 2014, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4192433/.
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