Let's see: I hour spin on Monday, 34 miles with some serious climbing on Sunday, and today I'll run 5 miles. I've discovered when on the spin bike I don't know how much resistance to add when the instructor tells us to "add a little!". I'm always adding too much, and when she says "back off light to moderate" I don't back off enough. Consequently, my leg speed is always low - but I am getting stronger (that's relative, guys!). I've found the size the sweat puddle on the floor and all over the bike is NOT directly proportional to heart rate!