Hey I am looking for new ways for cardio I swim, run, and ride my bike; but I really enjoying boxing and punching the bag. Yesterday I just rolled with my buddy for about 15 minutes then we spared for another 20 minutes and after all that I hit the bag for 5 3 min rounds. When I was done I felt very tried and my shirt was very wet. So is that a good cardio?

Also how many meters should I swim for a good work out
How many miles is good for a run
And how many miles for a good bike ride

I am 5'8 150lbs

Whatever you do if you are pushing yourself, exhausted or achy the next day you over did it.

It is also important to relax whatever muscles you worked out for 24 hours before exercising them again.

Like nohelp said, it really depends on the person. If you ask lance armstrong to bike 10 miles, he'll just laugh it off... meanwhile, if you tell average joe to bike 10 miles... well, he'll laugh at you too.

Usually, running 2 - 3 miles a day seems relatively sufficient for those who have a full time job. It's good exercise, and is very good cardio. If you can run 2 - 3 miles a day, and have more time/energy, push yourself more... try to run uphill, or beat your prev time.

Great you like sparring and bags... people often forget about this and it's a great way to hit your body in areas you often don't naturally do.

It's a little cheesy, but in addition to the normal gym or trail time, ill do 3-4 billy blanks tae bo dvds a week. Its easy to do at home when you have 40 min to kill, you can vary the routine easily by doing more or less footwork and using small hand weights for punching... and honestly, there are a couple of his vids that I still cannot to full time, as he does, all the way through. I can tell you which dvds I have if you are interested.

Also, jump rope. It seriously sucks. Try to do it for 15 minutes at a moderate pace. You'll be surprised at how good a workout you can get with a rope in a very short time.

Calories burned for it are in the list below, under rope jumping

Calories Burned During Exercise (http://www.nutristrategy.com/activitylist4.htm)

Dancing!! You don't have to be really good just move. It burns a lot of calories and it's really fun, I look forward to it. Look at it as fun not a cardio workout exercise