How important is recovering
 

After a tough/long ride, do you have to kind of let your heart rate drop while doing a little bit of easy riding, or can you just hope off the bike with your heart rate sky high and go and sit on the couch?

Hope that makes sense.

i do both

I dont know the reason but Ive heard that you should pedal easily or at least, walk.

Ricardo

I dunno, my heart rate drops pretty fast. Assuming I'm pedaling full tilt and slam on the brakes at my destination (which I don't usually do, I usually coast in the last little bit) with a heart rate of say 160, I'll be down under 100 within a minute or two.

I hit the shower, eat and then sit on the couch after a ride, which ends after an all out sprint to my front door.

i get light headed if i stop right after a sprint. i need to soft pedal for around 30 seconds or a minute to cool down a bit.

I think you want to separate your muscles from the cardio (heart & lungs) systems. For the heart/lungs, they operate based upon demand, so stress on them is highest under high work loads. As soon as you remove the demand for oxygen & bloodflow, they relax fairly quickly.

Your muscles on the other hand, get more damaged from work load more easily and quickly. I think that's the part that you're talking about right? After doing some 100% all-out screaming sprints, you really do want to ride easily for a couple of minutes to keep the blood flowing. The on/off muscle-contractions actualy help the veins pump blood back to the heart. The extra flow helps remove lactic-acid and start on the muscle rebuilding. Stretching and massage after the workout keeps this process going for a while after you get off the bike as well.

You should always keep riding to cool down your HR to a comfortable place before you stop.

Oh yeah, I stretch alot when Im done.