EXER-GENIE is an adjustable and variable resistance training tool that allows for a number of applications for all age groups, skill levels and development levels. The EXER-GENIE setup and attachments dictate the applications and you as the trainer, athlete, or fitness enthusiast dictate the place and the how the EXER-GENIE is used in a Rehab or Training routine, Circuit Training Program or Sport Specific Movement. The science of the EXER-GENIE with the 10' training line is to use an isometric contraction (60-70% max effort) at the beginning of the movement to recruit the muscle fibers, like the first 9 reps of an weight lifting movement, then to use variable resistance to maintain the (60-70%)muscle contraction intensity level through the range of motion. Making the Primary, Secondary and Tertiary Muscle Fibers familiar with demand in only 3 reps.The EXER-GENIE Speedline Setup is safer than bands, more versatile than chutes and more convenient than sleds. www.exergenie.com