What should you do when calf cramps stymie your runs? Our expert PT explains possible causes of one runner’s painful muscle cramps.
Q. “My calves tend to lock up when I’m running 5 to 7 miles at a 6:30 pace (three times a week) or at any distance more than 7 miles at any pace. When I slow it down to 7:30 to 8 minute miles, they’re fine for 5 miles, but when I run anything over 5 miles then they lock and cramp up again. It’s not a sharp shooting pain, but more of a dull ache — almost like a Charley-horse feel. It’s not that I have to stop in the middle of a run, but more that I have to hobble around for a few days after a run. It also switches from one calf to the other. I’m not sure what to make of it. Any ideas?”
— Rich, Denver
Dull, cramping symptoms like you describe that appear over time and at a certain running pace can suggest any of the following:
- a nerve compression (do you have a back injury history at L4, 5 or S1?)
- a circulatory compromise (anywhere from your abdominal aorta down into the local circulation such as a blockage or a weakening in a vessel wall)
- the beginnings of a compartment syndrome
In an acute or chronic situation, normal muscle (in this case, your calf) expansion is limited by the restrictions of its non-elastic fascial “covering.” This can be because of inflammation or injury within the muscle itself and a subsequent pressure build up in this finite space. It can become a life-threatening situation if the pressure continues to build and circulation and or neural tissue becomes severely compromised — tissue death can occur at this stage.
Most runners seem to remain in the chronic stage, when pressure temporarily builds up with activity, and once the activity is stopped, so do the symptoms; or, in your case, you wind up with a decent amount of post exercise soreness.
All of the above scenarios and diagnoses would involve an evaluation by a doctor. Tests include imaging studies for nerve and circulation issues; and compartment syndrome tests are unreliable at best – so you’d need to have internal pressure testing done when the symptoms are brought on, and even then there is no concrete data on what pressures are considered “normal.” So this leaves you with a range of possibilities.
I’d have it checked out by a sports physician MD.