Many people have tried to explain Crossfit to you. The workout is posted each day on a three day on, 1 day off schedule on http://www.crossfit.com
(wfs) What you see posted each is the workout that you do that day, after an appropriate warm, usually about 10-20 or so. From the Crossfit FAQ page:
The "official" CrossFit Warm-up is in the April 2003 CrossFit Journal.
3 rounds of 10-15 reps of
Samson Stretch (do the Samson Stretch once each round for 15-30 seconds)
Overhead Squat with broomstick
Note that for a workout that's dip or pullup-centric, you might want to do something else in the warmup.
I like to work on double unders as part of my warm. That is a good cardio pump for me.
If you are not able to do the WOD (workout of the day) as posted on the website, you should scale to your ability.
This website: http://www.crossfitbrandx.com/index..../viewforum/16/
wfs has each day's WOD scaled for "Big Dawgs", "Pack" or "Puppies". Pick a scaling level and do the WOD with good form and as intense as you are able. If you are unable to do 3 days on, 1 off then start with 1 day on, 3 off but give that one day your most intense effort. Work to 2 on, 2 off, then to 3:1.
IF YOU DO THE ABOVE, YOU WILL GET THE BENEFITS OF "30-60 MINUTES PER DAY" OF CARDIO EXERCISE AS RECOMMENDED BY YOUR DOCTOR. IT MAY NOT BE EXACTLY 30 TO 60 MINUTES, BUT YOU WILL GET THE PHYSIOLOGIC BENEFIT THAT YOUR DOCTOR RECOMMENDS. (Caps added for emphasis, pardon the "shouting")
The program will be different EACH WORKOUT. That is the benefit of the program is that you are CONSTANTLY VARYING your exercise regimen with FUNCTIONAL EXERCISE that you perform AT HIGH INTENSITY.
I know that this next suggestion will not be "free"....find a Crossfit affiliate in your area and follow their programming.