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Muscle cramp can cause serious problems for runners, from slowing us down to preventing us running at all! Our expert gives his advice on dealing with this frustrating problem


Q: I have been running for two years and have finished two marathons, Leicester and London, but both times I suffered from leg cramps from 23 miles. This problem is costing me time as I still have plenty of energy and the pace to run but the cramping slows me down.

For example, I finished London in 3.15.05, missing a good for age time (I’m 43) by 5 seconds and looking at my Garmin splits I was down for 3.05 so you can see my frustration. I am part of a running club so I train and race regularly. I have no diet or hydration problems. How can I cure this problem?

Stephen Penney

A: Great question and well done on achieving such great times despite your cramping problems. The truth is, cramping is a problem we do not fully understand but some individuals are clearly predisposed to get them. The good news is there are plenty of things you can try.

The two key areas you need to focus on are:

  • Hydration and electrolyte intake
  • Training, fitness and race pacing

Dehydration and electrolyte disturbances have been the traditional explanation for muscle cramps for 100 years, despite a lack of hard evidence. The problem is that studies looking at large groups of people during marathons fail to find any correlation between hydration status and cramping.

Despite this, we know that for cramp-prone individuals, supplementing with electrolytes during a race does help and proper hydration with adequate electrolytes is essential for peak performance. Use a hydration-specific drink such as OSMO active hydration with at least 300mg sodium per 500ml. If you can’t get that during your race, then electrolyte supplements such as salt sticks have also been shown to be effective.

More recently, fatigue-related disturbances in muscle reflexes have been thought to be the real cause of cramps. When we run, tendons are loaded and to prevent overloading, negative signals are sent back to the muscle via the spine to stop muscle contraction. At the same time, to prevent muscles becoming overstretched, positive signals are sent again via the spine make it contract. As we get more fatigued there is a decrease in the negative signals and increase in the positive signals, leading to cramps.

Regular stretching is essential and will help prevent cramping if done regularly. To address the issue of fatigue, you need to look at your training and racing strategy. Are you really doing the right training for a 3:05 marathon or are you training with slower club mates or skipping the hard tempo runs?

Ensure you have the mileage and intensity of training at the right speed to support your time goals. Finally, work out a pacing plan for race day and stick to it; if you set off too fast you are far more likely to cramp than if you start at your target pace.

Take these steps and you should see some improvement – happy cramp-free running!

Graeme Stewart is a professional triathlete and coach with 10 years experience in medical research, Graeme is a UK ambassador for OSMO nutrition and Enhanced Nation. graemestewart.com