First, let me say I'm 65. I've got mild angina though I've never had an attack, and also AF (atrial fibrillation), which comes and goes infrequently and usually hits when I get dehydrated.

I've been a cyclist most of my life starting with a club and racing when I was young and then commuting and I've always been interested in what's going on in the cycling world. I'm also a potholer/caverand therein lies one of my problems.

First, here's the cycling bit: when I've been out for a longish ride of 50 miles or more I quite often get excruciating cramp down the inside of my thigh when relaxing; it's so bad that I finish up jumping around like a marionette with a puppeteer who is having a seizure.

There's no amount of stretching that can relieve it and no massage I can do to stop it. Is there anything you can suggest? The doctor sent me to a physio, but they didn't sort it out at all.

Now the potholing bit: after climbing out of a pothole hundreds of feet below ground using the Single Rope Technique which looks a bit like a ‘monkey on a stick' movement using the legs to propel one upward, I get the same thing happening. I did Alpe d'Huez, Grand Colombier, Mont Cenis and Télégraphe this year, so I'm not that unfit. Any ideas?

Ray Duffy

There are two main schools of thought as to what causes exercise-induced muscle cramps: one being that the cause is muscular tiredness, and the other that dehydration is the culprit.

A study undertaken by the Medical College of Georgia, Augusta, USA, identified that both muscular fatigue and a sodium deficiency are the most probable causes of muscle cramps during and after exercise. So in your case, it could well be a combination of both of these things.

You already do lots of stretching, which is great, because shortened muscles with sustained contraction may be particularly vulnerable to cramping. Ensure that you are doing appropriate stretches which specifically target the adductors and associated muscles. Don't forget to finish each ride with 10-20 minutes of gentle riding as a cool down and ensure you take adequate rest periods to enable your muscles to recover on a regular basis.

To combat the risk of losing valuable sodium and chloride through dehydration, take on a minimum of 500ml of water, which includes an additive containing electrolytes and minerals before exercise, and again for every hour of exercise thereafter. Use this strategy for both cycling and potholing.

Rob Mortlock is a British Cycling coach

This article was first published in the November 21 issue of Cycling Weekly. Read Cycling Weekly magazine on the day of release where ever you are in the world International digital edition, UK digital edition. And if you like us, rate us!