500 jumps with a jump rope

Got halfway there, and then re-injured my knee. Now my main activity is Xi-gong and bicycling (which surprisingly doesn’t tax the knee). It would be nice to have it accomplished before mid 2012.

I’m trying to condition myself to go above 300 in a week or two. My difficulty is not the heart or the lungs, but tight muscles. So I stretch before and after.

Doing 275 jumps in about 10-15 min wasn’t difficult. My heart rate wasn’t excessive, and I felt I could go on for longer. But after a few hours I felt my legs where excessively tired and stiff.
I should stay below this number for a while and keep practicing.

Half way there—255.
I’m practicing every other day. My technique is getting better. Usually the first 30 jumps are painful, but it gets easier until the last 30 or so, when my legs give up. Surprisingly, I’m no longer out of breath at the end.

I started jump rope (could never to id well in my youth). Got to a 100+, but it’s getting difficult. My muscles get tired, and do n’t recover fast. 500 is over two humps. 00.