Even in the most urban environments, there is usually at least a park or two where you can bang out a great outdoor workout. This time around, however, I'm not talking about taking the proverbial walk in the park. No, I'm getting downright torturous with the outdoor workout I'm about to send you on.

You may want to send me hate mail after doing this workout, but start now and you'll be thanking me when Memorial Day rolls around and you're looking lean and fit for summer.

Warm-Up. Fill a backpack full of heavy items and wrap them in clothes or a few towels. You'll probably want to include a water bottle in that pack somewhere, too. Next, strap that backpack on and start jogging! Complete at least one full circle around the predetermined path.

Pull-Ups. Find a nice, solid tree that has a fairly even branch from which you can safely hang. Keep your hands just slightly wider than shoulder-width apart and perform as many pull-ups as you can. If you're really feeling strong, keep that backpack on and do them.

Hill Runs. Drop that backpack in a safe place (not that anyone is going to steal a backpack full of weights, but just in case) and sprint up a hillside. Once you get to the top, take a five second break and then amble back down. Give yourself a 30-second breather and then sprint back up. Do this a total of five times.