According to my Body by Science book, the body takes five to fifteen days to fully recover from a high intensity session. So it's obviously a personal thing. When starting out, if one does not improve at the next session, the likelihood is that the muscles may not have recovered.
Originally Posted by ShannonCC
At present I've been OK with 7 or 8 days. When I get back from vacation in two weeks time, I'll try decreasing recovery time to five days and see how I get on. I have also been HIT rowing after three days rest so at an eight day interval I do the strength training and two rowing sessions as I do the second rowing one after two days, leaving me two days before the next strength training bout. This is working for me, but may not for others.
Why use a sledge hammer to crack a nut when a steam roller is even more effective, and, is fun to drive.