Pec spasm WTF!

March 3, 2008 8:13 PM

What could be causing mild but annoying pectoral spasms?

My left pectoral muscle was twitching involuntarily and intermittently for about an hour yesterday. It's doing it again now, after not happening all day. It's not painful at all, just weird. At first I thought it was my heart, but it's definitely not. It twitches at a rate of about 120 bpm or so.

Physically, I haven't done anything really out of the ordinary. Last Thursday, I did two hours of judo and felt fine afterward. Saturday and Sunday, I was a little sick (cough, lower energy, stiffness in my wrists), and I did relatively light workouts that lasted about twenty minutes each. They consisted of pull-ups, push-ups, squats, and burpees on Saturday, and dumbbell snatches and swings and burpees on Sunday. Saturday's draining was a little more draining than usual, but nothing made me feel like, "Whoa! I can't handle this!" Sunday's workout felt like no problem. Certainly, nothing felt like it taxed my chest.

I might not be searching for the right things, so the only thing I can find that's somewhat useful is this, which says it's probably ignorable. It's still weirding me out, so I'd like to know more about it if possible. I'd like to know why it's happening, what I can do to make it go away, and how soon I can expect it to cease.

I'm 31, in reasonable shape, and was told I had no medical problems after a physical exam last year.

posted by ignignokt to health (8 comments total)

It happens to me (and in different muscles, too) pretty randomly. It goes away. Having a sports drink helps sometimes.
posted by porpoise at 8:29 PM on March 3

Oh, sorry, I'm speculating here but new motorneuron synapsing with muscles (especially developing ones) happens. During the initial stage, there are more than one neuron competing to be the one that makes the synapse with the muscle.

The nerves will 'randomly' fire and the muscle side of the synapse chooses which one to keep and which one to reject. Firing usually come in the form of bursts of high frequency spikes.

This could just be a violent version of this tug-of-war or it could just be a muscle that induces nearby muscle bundles to contract, upon contracting itself, and the normally unnoticeable effect is amplified. Again, just speculating, here.
posted by porpoise at 8:33 PM on March 3 [1 favorite]

I've had muscle spasms in the same place for as long as three days straight. It'll go away... eventually.
posted by crunch buttsteak at 8:57 PM on March 3

I get these in my legs fairly regularly. Sometimes in different places as well, like my pecs or hands. I'm not dead yet, if that's any comfort.
posted by SlyBevel at 11:03 PM on March 3

The twitch could be your body's friendly heads-up to a Thiamin deficiency. I suggest looking into that (sorry--no links handy) to see whether the other symptoms line up with your own.

If they do, a B-complex vitamin supplement might be a good idea, even if the spasms stop before you start taking it (which I suspect they will).
posted by whoiam at 12:01 AM on March 4

Fasciculation
posted by fire&wings at 2:30 AM on March 4

Eat a banana.
posted by dendrite at 4:06 AM on March 4 [1 favorite]

The nutrient deficiency ideas are good, but in my case, I get a lot of thiamin from a multivitamin I take, and I eat a lot of almonds, so I probably get enough magnesium. I also eat a banana every day, although I haven't eaten one at the moment I get the spasm. I'll try that.

It's also good to know that there's a term for it, and that other people have had them without incident.
posted by ignignokt at 11:18 AM on March 4