Last Saturday, I did a 67-mile, 5,800-foot ride in 90F heat. Not the hardest ride I've done, but it was up there.

At the 47-mile mark, I stopped at a farmers market for 30+ minutes, rehydrated with water and fresh-squeezed OJ, and ate a fig bar. Five minutes after restarting, the inside tops of my legs began to cramp and spasm. The pain came and went, and I was able to finish the ride, but with great difficulty.

Any idea why this happened, and how to avoid it next time?