hey...i dont wear shoes when i jump rope lol i jump inside lol...but yea i find my calves hurt afterwards...cuz i over did it...so yea lol...and i do it whenever i feel good enough to exercise...around 3 in the afternoon....i did it for 40 mins lol but not straight...1 minute then 10 secs rest and yea that was my routine but u burn alot of calories