The biggest obstacle: Muscle Cramps

Race time predictors extrapolate from previous races to predict future times. Plugging in my half marathon time, the resulting race predictions are accurate — the mile time is exactly my personal best, in fact. The predicted marathon time is 2:39:30, or a pace of 6:05.

My best marathon time, however is 2:50:10, a pace of 6:30 minutes per mile. So why is it 10 minutes off the prediction? The biggest reason is muscle cramps. In every marathon I’ve ever run, muscle cramps have made a show-stopping appearance late race.

Over time, I’ve lasted longer before that inevitable feeling of rubber-band muscles. In 2014, cramps hit at mile 19 (2 hours 21 minutes) in the Pittsburgh Marathon. I delayed them until mile 21 in my next two marathons: The Woodlands Marathon in 2015, where cramps set in after 2 hours and 19 minutes, and the California International Marathon, where they occurred at 2:13. I ran Boston on a warm day in 2017, and signs of cramping struck at mile 13 — a clue in their cause. And most recently, I got up to mile 24 (2:25) in The Woodlands Marathon until cramps hit, costing me third place.

While scientists don’t fully understand the causes of muscle cramps, there are two major theories:

1. Nutrition, including dehydration and depleted electrolyte levels
2. Muscle fatigue

In my personal experience, there is evidence for each of these causes. It does appear that cramping appears more often on warm days, suggesting dehydration or an electrolyte imbalance. The Boston Marathon stands out as an anomaly in my marathons, as cramps set in at an early mile 13. I ran it on a hot day, with temperatures in the low 70s and a humidity level of about 30%. During a training run on a warm (low 70s, 90% humidity) day in Miami, I felt signs of cramping at mile 17, the only time I’ve experienced cramping during training.

Cramps are also not limited to my legs. I often get bicep and tricep cramps, suggesting that the problem is nutritional, rather than a muscular problem which would only affect my legs.

There’s also evidence for the theory that accumulated muscle fatigue is causing cramping. I don’t experience muscle cramps during long training runs, even those reaching 24 miles — past the point where I cramp in races. This is likely because my training runs are slower than race pace, leading to less muscular fatigue. And I’ve been putting off cramps for longer as I’ve gotten fitter, without making significant changes to my race or pre-race nutrition plan.

Cramping is the biggest roadblock to running a 2:37 marathon. My goal is to finish a race-effort marathon without experiencing muscle cramps.

To accomplish this goal, I must experimenting with a number of strategies to prevent muscle cramps. First, I need a baseline. I’m going to run until I get muscle cramps, or hit 26.2 miles. I’ll then try out each of the following techniques on similar runs, noting when and whether I get muscle cramps.

1. Increased sodium, via high-sodium GU gels
2. Pickle Juice — for reasons unknown, pickle juice reduces the duration of muscle cramps
3. Higher volume of sports drink intake during the run

If one of these strategies works, I’ll add it to my race arsenal. If none do, then these long cramp-inducing runs will serve to strengthen my muscles, preventing the second cause of cramps, muscle fatigue.

Have a story on how you overcame muscle cramps? Leave a comment!