There's two things I like about resistance training:
1). You only work with your own body weight, so there's less chance of injuring yourself by pushing your muscles beyond their limits. My freshman-year roommate was a body builder type, worked out every day, took a lot of supplements, etc. One day during supersets, he tried to lift an obscene amount of weight, and arrived at our dorm room with both rotator cuffs torn.
2). It improves your ligaments and flexibility along with your muscles. Back when I practiced TDK with my sister, our teacher tried to emphasize this by leaping in a very narrow arc over a kickboxing stand, safely rolling back to a standing position on the other side. Neither of us ever matched it, but it was impressive to see a physically strong man manage that kind of agility when the aforementioned roommate couldn't tie his shoes with any alacrity. >>
Anywho, just finished my set, so I'll try my best to describe the process. Maybe I'll sell some of you on it.
With the resistance straps, you don't perform sets of multiple motions. Instead, exercises are given in "start" and "end" positions. You go from start to end, hold the pose for thirty seconds at a time, and return to the start, to perform the exercise. The slower the action, the more the muscles strain. You keep tension by working with gravity and the resistance of an "anchor point," in my case a door frame. A simple workout looks like this:
Chest Fly: Standing away from the anchor point, you balance on your toes and stretch your arms outward. This makes your body lean forward, pulling the muscles towards the handles. You hold this pose for thirty seconds, return to start, and do this again twice more. Its basically like doing a push-up in the air.
Chest Row: Same as above, but facing the anchor point and leaning back.
Bicep Row: Same as the Chest Pull, but with your arms tucked in close.
Back Stretch: Imagine trying to sit down while keeping tension on those bands, and you have a basic idea of the stretch.
Rollout: Not gonna lie, this one really sucks. You face away from the anchor point, balance on your knees, and stretch as far outward as you can while keeping tension on the bands. I swear, it feels like your abs are splitting. @_@
In all it takes about eight minutes to do a simple workout. Stretches your muscles, pops your joints, and you feel pretty "worked out" at the end despite the minimal time spent.