--- For what it's worth, here is a thread I posted in the Fifty Plus forum entitled "How I Cured Leg Cramps" that talks about pedals:
Originally Posted by Sir Lunch-a-lot
I had been bothered by leg cramps after my commutes and finally tracked down the cause. It was the cheap brands of platform pedals I was using. I have trashed two pairs of platform pedals in the past five years. The cheap ones are not rigid enough; they flex under pressure. This flexing causes strains in the ankle and leg muscles which have a cumulative effect over time and cause leg cramps.
On the advice of my LBS, I finally bought some Redline Alloy Platform Pedals which are a solid one-piece construction plus they're wider and provide a solid foundation for my feet. The leg cramps have totally disappeared since I installed the Redlines on my bicycle.