A reader struggles with an unexplained issue after a series of long runs.
Q: I picked up running in my mid-forties, and have run two marathons over the past two years. The first went great. I’m not super-fast, but I was thrilled to finish in 3:49. Then my second…not so much. I started getting cramps at the 35th kilometre, hobbled over the finish line, and then horrendous cramps took over both legs, and I had pretty significant tingling over my entire body, especially my hands, arms and face. It felt like if the tingling had progressed, I would have fainted, but thankfully I didn’t.
I was in the medical tent during this episode. I had my vitals checked, and according to the doctors, they were all fine (aside from a moderately elevated heart rate). I took a GU pack every 10 kilometres, drank at just about every aid station, though I didn’t have a ton of water before the race started (maybe something like 350ml).
I have never had cramping before, though I did have some of that whole-body tingling after some of my longer training runs (25+ km). I asked my doctor about the tingling, and he sort of shrugged. I’ve Googled this a ton, but haven’t found anything definitive.
Then, over the weekend, about 15 minutes after a 24-kilometre run, I got really bad leg cramps and had the tingling sensation again. Just to be safe, I had my wife call the paramedics (mostly so she wouldn’t have to deal with me writhing in pain all by herself). They showed up, and said all of my vitals were fine: Blood pressure, O2 levels, heart rate. They left about ten minutes after they arrived, as I had recovered by then. During the run itself, my pulse was in the 120-130 range, which seems totally acceptable.
The cramping I sort of understand: I’m either not drinking enough (or not taking enough salts), or it’s just plain-old overuse. I’m sort of stiff, so perhaps my gait is bad and puts extra pressure on my calf muscles.
But the tingling…what is going on? Is this my body telling me to just stop distance running? Could this be corrected by a different training regimen? I’d like to run another marathon later this year, but I don’t want to risk my health.
This is an interesting problem. I will have to admit that your whole body tingling has me stumped. I usually associate tingling in the hands, feet, and lips with something called hyperventilation syndrome. I have seen people with tingling in their arms, legs, and perioral region of the face (around the mouth); but not in a person’s whole body.
That doesn’t mean it can’t occur, just that it has not occurred when I have been on site.
Hyperventilation syndrome is caused when a person’s rapid breathing blows off more CO2 than their body is producing, setting up an imbalance called respiratory alkalosis.
Usually this is caused by anxiety, stress, or a panic attack, though some severe medical conditions can also cause this.
Running obviously involves rapid breathing, which increases oxygen to (and gets rid of the CO2 produced by) your muscles. This exchange is usually well balanced during exercise.
I have seen runners experience hyperventilation after a race when the high respiratory rate persists after a person has stopped exercising. This is often related to stress and anxiety, though it seems to occur without perceived stress or anxiety on the part of the athlete.
Hyperventilation can also be associated with exertional heat stroke and hyponatraemia (low sodium levels). But your story does not fit with heat stroke and you do not seem to be stressed or anxious about your performance.
Since you drank fluids at nearly every station, it is likely that you were not dehydrated. It’s possible that you had too much fluid on board. It is possible to drink more than you should, and end up with low sodium levels. This is called dilutional hyponatraemia, and is usually associated with an inappropriate level of the anti-diuretic hormone vasopressin that keeps your kidney from getting rid of extra water.
One solution is to weigh yourself pre- and postrun to get an estimate of your sweat-related fluid losses. (Your body weight loss + fluid intake = sweat losses.) This will help optimise your fluid replacement.
It is important not to drink more than you lose. If you drink a lot of fluid during the day, you might try cutting back the volume for a few days to see if that changes your cramping. You likely get adequate electrolytes in your daily diet. If you do not know your sweat rate, drinking when you feel thirsty may reduce the risk for hyponatraemia.
Cramping is not well understood and there is controversy about its origins in athletes. The cause probably lies on a spectrum from some level of dehydration to overuse of the muscle. I generally consider cramping as a problem related to overuse of the muscle with the caveat that dehydration and heat can also stress the working muscle.
I have seen muscle cramps at the marathon finish in all race weather conditions and in football in early season games, especially when it is hot, and when the playing surface or environment temperature changes (such as when outdoor teams habituated to cold weather move indoors to artificial turf).
Hyperventilation can cause muscle cramps in the hands called “carpel spasm”, but your cramping sounds more extensive. Cramps can also occur in exercise associated hyponatraemia and in exertional heat stroke.
I think it would be worth a visit to your physician or a sports physician to assess your fluid and nutrition habits, your electrolytes and kidney function, your life stresses, and your training schedule and volume.
