These videos emphasize FRC principles: progressive (PAIL) and regressive angular isometric loading (RAIL). These techniques help teach the central nervous system (CNS) how to control and function in newly acquired ranges. Utilizing isometric contraction teaches the nervous system to have ACTIVE control over a particular range (i.e. shortened or lengthened positions). These techniques help expand USABLE range of motion. In addition, PAILs and RAILs will help build strength and tissue adaptation in both the shortened and lengthened ranges of motion. A key component while performing PAILs and RAILs is to irradiate (create tension) throughout the body.
In order to perform PAILs and RAILs, statically hold a 90-90 hip position for 2 minutes. After the 2 minutes, you irradiate throughout the entire body and perform a PAIL contraction with the right leg by driving the leg into the ground, ramping tension up to 100% effort by the end of the 10 second count. After the PAIL contraction you reverse into a RAIL contraction--again, ramping tension up to 100% effort within the 10 second count--whereby you ACTIVELY bring myself further into a new range. After completing that cycle (Hold position: 2 minutes, then PAIL/RAIL contraction) you are in a newly acquired range and you should repeat the sequence. These techniques are very taxing to the body and should be performed with 100% focus!