Questions about P.A.I.L.s and R.A.I.L.s are common with Kinstretch and Functional Range Conditioning. We will explain what are P.A.I.L.s and R.A.I.L.s and how to progress them. In the end, we want you to be feeling what are you supposed to be feeling.
As part of our Kinstretch Pro Tips in our Elite Video Membership, Ian breaks down all the concepts of Kinstretch in detail in a series of videos.
Major Keys
1. P.A.I.L.’s/ R.A.I.L.’s can be applied to any stretch.
2. This is how we EXPAND range of motion.
3. Time under tension matters. This is not meant to be a quick process.
4. The L stands for LOADING. When people think of stretching they rarely consider that we are applying force to the tissue internally and as a progression externally.
5. Lastly, Do not get lost in the acronyms and science. You can be very successful in class just knowing what lines of tissue to contract.
P.A.I.L.’s/ R.A.I.L.’s is an isometric loading protocol created by Dr. Andreo Spina. In other words, this is when we are stretching and contracting the muscles that are being lengthened/ stretched followed by the opposing muscles to pull us deeper into the stretch.
P.A.I.L.’s = Progressive Angular Isometric Loading
This is the first contraction in the sequence in which we tension the muscle that is being loaded/ stretching.
R.A.I.L.’s = Regressive Angular Isometric Loading
This is the second contraction of the antagonist or tissue that is shortening to achieve a new range of motion. You can think of this as actively pulling yourself into the new range of motion.
The active component of P.A.I.L.’s/ R.A.I.L.’s ensures we are achieving USABLE range of motion.

P.A.I.L.’s/ R.A.I.L.’s can be added to any progression or regression with the right cues and intentions.
How Do I Progress My P.A.I.L.’s/ R.A.I.L.’s?
Let’s lay out some examples and guidelines.
1. Own two minutes of just being able to breathe in for 4 and out for 4 exploring lines of tension. Firstly, before anything let’s make sure we can achieve the position and breathe.
2. Let’s add some specific tension implementing low-level PAILs. After step 1, perform 1-3 sets of 30-second low level 0-30% Max Voluntary Contractions. In between rounds take 3-5 quality breaths sinking into the stretch.
3. Now let’s show how strong we are at getting out of this position by ramping our PAILs to a full 100% MVC. This goes far beyond pushing down as hard as you can. Pick an increment of 1-10 % and meticulously control the ramping of tension.
Visualize someone slowly turning the volume knob up. What you will discover is maintaining continuity is very difficult where you might go from 75 to 65 and then jump to 90 percent of your max.
When you are a real Jedi…… reverse this and work on slowly turning the volume down with precision.
Aim for 10-20 seconds to get to 100% and 10 maintaining the max effort.
This is an application of Dr. Andreo Spina’s Isometric ramping which trains the nervous system for both up and down-regulation.
4. The next addition is the one and only RAILs. We contract the other side of the joint to ACTIVELY pull us deeper into the position.
By doing this we are creating a ROM that will be useful in the future. This contraction is after your max PAILS and lasts 10-30 seconds.
5. Lastly, we take a few breaths and sink back into the stretch. This concludes one official round of Level 3 PAILS/RAILs. This is training. This is what leads to some of the most intense soreness.
For an example of P.A.I.L.s and R.A.I.L.s in action, here is the classic couch stretch.
We hope that helps you wrap your head around P.A.I.L.s and R.A.I.L.s and always if you have any questions drop a comment below.
For more Kinstretch Pro Tips you can visit our Elite Video Membership and take a free Kinstretch class on us!