Interval hill sprints
Ever noticed how sprinters are always lean and muscular? Take a page from their book, and hit those hills. Run as fast as you can while maintaining control of your speed up the steepest hill you can find. Walk down, then repeat one to three times. This will really build your leg power, and give those glutes a workout.
No hills in your park? Find a set of stairs or bleachers and as quickly as you can, run up the stairs. Walk back down and repeat two or three times.
Picnic table lift
Position yourself into a squat under one end of a picnic table with your hands on the underside of the table. In one clean movement, stand up, and press your end of the table into the air. Extend your arms. Slowly lower the table, and repeat for as many reps as you can do with good form. This exercise works just about every pushing muscle in your body, especially the legs and shoulders.
Picnic tables chained down or cemented to the ground at your park? Get a basketball, get into a squat position with the ball positioned between your knees, then stand raising the ball above your head. Repeat movement for 20 to 30 reps.
Monkey bar pull-ups
You knew it was coming. Good ol' pull-ups. Get positioned under the set of bars that you can reach on your tiptoes. Grab the bar with an under-handed grip, or with your palms facing each other. Pull yourself up to the bar, lower yourself slowly. Once again, do as many as you can with good form. If this is too difficult, try a few jumping pull-ups, still focusing on a slow descent.
Going through each of these exercises three times will give you an efficient, functional, and effective workout that will get you out of the gym, and into a previously untapped resource.
Have fun, and good luck.
Chad Smith is a local certified personal trainer and fitness expert. He can be reached via e-mail at firstname.lastname@example.org