IMHO try working a heavy bag some. I can run miles and never work a sweat like hitting a heavy bag. Total body and fun too.. If nothing else you can relieve a little stress while your at it. The more affluent you become with the bag the more fun it becomes as well. If you feeling really froggy throw in some leg kicks if you have access to big enough bag. Great cardio.

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You come into the world weak, and you will leave the world weak. What you do in between is up to you!