davidji
Taylor's Version
+1 on Potassium. Dried banana chips are a good source.
Also, Amazon has an assortment of electrolyte powders where you're not getting sugar with it, like you do with sports drinks.
I forgot the specific items that were recommended here, but I remembered potassium & bananas, and had some bananas this week including one this morning.
My other calf (left gastroc) locked up hard during my workout tonight.
A few years ago an alternative health practitioner prescribed me a few things for this. a mineral supplement and two foods (both greens). It worked then. The supplement was discontinued and I started using the replacement, and that seems OK, but I haven't been eating the foods regularly lately, and I think next step is go back to that.
A lot of these occur the next day after my calves got worked, and most occur after maybe 2 1/2 hrs of motorcycling that day. Maybe I need a geezer glide with floorboards.
Next I think is add in the two greens that helped before, and maybe coconut water. The Geezer Glide can wait.
FWIW it happened 10 years ago when I was free soloing a relatively easy route. Both calves simultaneously. Thought I was minutes from a death fall. I was wrong...