Have you ever finished a workout, did your cooldown, and then noticed a muscle twitching non-stop? No doubt about it, a twitching muscle is irritating, and you might wonder how normal it is to have a muscle that keeps fluttering when you aren’t telling it to move! What causes a twitching muscle after a workout, and is it something you should worry about?
First, muscle spasm is not the same as a muscle cramp. A twitching muscle is a muscle spasm, in contrast to a cramp is where an entire muscle tightens up and holds the shortened position. Muscle cramps can be excruciatingly painful and sometimes awaken people from sleep at night. However, muscle cramps are short-lived and last from seconds to minutes. In contrast, muscle spasms are more irritating than they are painful. With a spasm, a small area of muscle contracts involuntarily and can last for minutes to hours.
What Causes Muscle Spasms?
Scientists don’t understand what causes muscle spasms. Since they’re more common after a workout, one theory is that muscle spasms are brought on by muscle fatigue. Therefore, it’s not surprising when a spasm hits you after an exhausting workout. They also appear to be more common when people try to challenge their muscles in a way they’re unaccustomed to. In other words, you ask your muscles to do more activity than they’re used to doing. It sometimes happens after taking a break from exercise and then jumping back in and trying to work out at the same intensity when you have deconditioned muscles.
Muscles prone to twitch and spasm when they’re tired include the biceps, quads, and calf muscles, but you can get a spasm of a smaller muscle that’s unrelated to exercise. You may be familiar with the annoying twitch some people get in their eyelids after sitting in front of a computer too long. It’s a similar phenomenon to a muscle spasm in a larger muscle. The muscle contracts erratically for hours. It certainly makes it harder to do computer work!
Blepharospasm can persist for days and sometimes a week or longer before going away on its own. You can develop blepharospasm due to too much caffeine, stress, eye fatigue, dry eyes, eye irritants, and other factors. Eyelid spasms are usually not serious or indicative of an underlying health problem.
Does Dehydration Play a Role in Muscle Spasms?
At one time, scientists thought dehydration was a factor in muscle cramps and spasms, but the link between twitching muscles and dehydration is indirect. When you sweat and lose fluid, you also lose electrolytes, including sodium and potassium. Losing electrolytes can cause a muscle to get the wrong electrical signals and either cramp or spasm.
One small study found that drinking water after a workout increases susceptibility to muscle cramps while drinking an electrolyte-rich solution reduces it. So, it would seem that electrolyte loss plays a bigger role in muscle cramps, but we’re talking about spasms and it’s not clear whether they have a similar etiology to cramps where the muscle shortens but doesn’t twitch.
Is a Muscle Spasm Serious?
When a muscle twitches for more than a few minutes, some people question whether they have a life-threatening neurological condition like Lou Gehrig’s disease, or ALS, a progressive condition that damages the lower motor neurons that carry information from the brain to the spinal cord and muscle that tells the muscle to move. Although people with Lou Gehrig’s disease often have muscle spasms, they almost always have muscle weakness too. If you don’t have muscle weakness, it’s unlikely that you have ALS. However, always investigate muscle spasms that persist for more than a few days by seeing a physician.
Can You Prevent Exercise-Induced Muscle Spasms?
One way to, possibly, lower your risk of muscle spasms is not to overfatigue your muscles when you train. But even doing this doesn’t guarantee you won’t get one since we don’t understand what causes them. But to lower your risk, don’t train the same muscle group again until at least 48 hours have elapsed. Give your muscles enough time to fully recover between workouts. Also, don’t train to failure every time you work out. Over fatiguing your muscles can predispose them to spasms. Make sure you’re giving your body enough relaxation and recovery time between workouts too.
If you’ve had muscle spasms in the past, sip an electrolyte-rich beverage rather than pure water when you train. Coconut water with a pinch of added salt is a good substitute for a sports drink. If you have frequent muscle spasms during or after training, see your physician for testing to make sure you don’t have a low potassium, sodium, magnesium, or calcium level. Imbalances in any of these electrolytes can cause muscle spasms or muscle cramps. Taking certain medications, like diuretics, can cause an imbalance in sodium, potassium, magnesium, or calcium too.
What about Stretching?
If you get a leg cramp, stretching the muscle can shorten its duration. There’s also some evidence that stretching before bedtime reduces the frequency of nighttime leg cramps. However, muscle cramps aren’t the same as muscle spasms and there’s no evidence that stretching shortens their duration, but there are few studies looking at this issue. It can’t hurt to stretch, but don’t be too aggressive! If you stretch a muscle too far, it may react by pulling back and this can cause the muscle to go into a spasm.
The Bottom Line
Muscle spasms are annoying and, sometimes, frightening to people who have never had one. In most cases, a muscle spasm that lasts for minutes to days isn’t a sign of a sinister disease involving your nervous system or muscles. If you have persistent or frequent ones, check with your doctor for blood work to rule out electrolyte imbalances or another cause of twitching muscles.
References:
· Mayo Clinic. “Eye Twitches”
· BMJ Open Sport Exerc Med. 2019; 5(1): e000478.
· Mayo Clinic. “Amyotrophic lateral sclerosis”
· Medical News Today. “Causes of muscle twitches and how to relieve them”
· Journal of Physiotherapy. Volume 58, Issue 1, March 2012, Pages 17-22.
Related Articles By Cathe:
Muscle Cramps vs. Muscle Spasms: What’s the Difference & What Causes Them?
Muscle Cramps Hurt! Here’s Why They Happen and How to Lower Your Risk
Should You Stretch Before a Workout and What Type Should You Do?
