feet cramps while running long distance race

[hiltonspt]

I have been racing for 15 years or more. The last couple of years I have been getting feet cramps towards the end of the half marathons I've been doing. It started out after the race was finished, just slight cramping and over the last couple of years has progressed to the last 4 miles of the race. In practice, I do not have issues with this. I do drink water before a race and eat a Cliff bar. During the race I do some type of electrolyte replacement and water. I tried a daily potassium supplement a couple of weeks before my most recent race, to no avail. I teach yoga 3 times a week, so I get plenty of stretching with that. My training runs are slightly slower than race pace. I tapper the week before the race.
Any ideas of what I could do differently?

[Heidi]

It's a tricky one as the cause of cramp isn't entirely known and may be dehydration related, but is more likely fatigue. I take it you wear the same running shoes for training and racing? Maybe running slightly faster in races affects your gait and so puts different stresses on your foot muscles? Just a thought?