If they are having you do "jumps" and it is not comfortable for any reason, just don't do them. I detest jumps and just stay seated. I do like longer climbs out of the saddle, but the jumps are not very useful in my opinion.

Also check your seat height. That could affect your circulation to your feet if it's too high, or if the saddle hits you wrong. Do you bounce when you spin very fast? If so, increase the resistance and slow down until you stop bouncing. Bouncing can cause problems, too, and I imagine it could affect the feet.

If you find relief, let us know what you did. I'm sure other people have the same problem.