PAILs/RAILs - Progress/Regressive Angular Isometric Loading. This is a very important concept for the classes. Learn more about them here!

To put it short, PAILs/RAILs is just isometric loading. In traditional flexibility work, we go into a stretch, and we passively hang out there. When we do this, we develop better flexibility. Flexibility = the ability to passively achieve a range of motion. Though just because you do flexibility training, it doesn't mean you'll improve your active mobility, or your ability to actively achieve that same range of motion.

In PAILs/RAILs we essentially go into that same stretch, and while we still utilize a passive stretch element, we also add in isometrics (PAILs/RAILs) after to create stress on the lines of tissue that are at their end-ranges of motion. This is essentially end-range strength training. When we do this, we develop better Mobility. Mobility = the ability to actively achieve a range of motion. Good mobility work IS (end-range) strength training.

When we get into a certain base position for PAILs/RAILs. It's important to find the stretch. Just like we do in regular flexibility work when we utilize traditional stretches. We go into a range of motion that gives us that stretch sensation. We want to find those stretches in our PAILs/RAILs bases. It's important to note, everyone will find the stretch at different ranges of motion. Give yourself a little wiggle room to explore your body and to find the stretches in each base. Though never go into any stretch that creates any pain or a sharp pinch.

It's important to know - PAILs is one contraction, and RAILs is another. We always do our PAILs contraction first, and then RAILs. So PAILs/RAILs is two contractions total. When we utilize PAILs/RAILs, we're giving direction to the isometric force. This direction could be up, down, left, right, or rotational. The PAILs contraction will be in one direction, and the RAILs contraction will be in the opposite direction. In the classes I will give you cues to the direction of the PAILs/RAILs contractions for each base position.
The PAILs contraction is a slow build up to your greatest safest effort. It should take around 5-7 seconds to get up to your max effort. Think of it like a volume dial, and you're slowly turning up the music.

The RAILs contraction is a quick (but still controlled) transition to the opposite direction, while maintaining that same high effort you had at the end of your PAILs contraction. In RAILs, it's very common to cramp. If this continues to happen, you will have to lower the transition speed from PAILs to RAILs, and you may have to lower the intensity in which you RAILs. The goal is to produce as much force as you can without going into a full cramp - so if this continues to happen make those slight adjustments.

If you're new to PAILs/RAILs, your "max" effort should really max out around 40-50%. It's important to start off slow and go at your own pace. Listen to your body. For intermediate students they could be around 60-80%. For advanced around 75-100%. The goal is to start off slow, and progressively build up the intensity through weeks and months worth of training. Similar to conventional weight lifting. You initially start off at a lower weight, and after 2-3 weeks you gradually increase the weight a little bit. The same approach can be done here. If you're new, start off at lower intensities for the first few weeks. Once you feel comfortable, you can slowly increase it a little bit more. Progressive overload is the key, and always listen to your body. It's completely normal to feel sore and tender for 1-2 days after doing PAILs/RAILs. Though if you're super sore for 3-4+ days, you're probably giving too much effort too soon, and will need to back off just a little bit. On the flip side, if you barely feel anything for the next 2 days after PAILs/RAILs, you know you can push it a little bit more the next time.

At no point should you ever feel any pain during these movements. PAILs/RAILs is extremely challenging, and there will be lots of discomfort, but we never want that to increase to pain. If you feel pain or sharp pinch in a certain range of motion, back out of the range until you don't feel that pain anymore, and then try to get some good quality work in that range.
PAILs/RAILs is my favorite tool to develop end-range strength and expand mobility. This is a big part of operation buttery joints. Like anything new, it will take lots of practice to master. Stay consistent, and it will pay off in the long run. 
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*If you're Hypermobile!* 
Essentially you have a lot of passive flexibility, though you're likely to have a bigger gap between your passive vs active ranges of motion. When going into PAILs/RAILs bases, find the end of your ACTIVE range of motion, and then only go about 10-15 degrees further (not more) into your passive range. You may not feel a stretch sensation as much, and you'll likely be able to push further than that, but do not. Stay within 10-15 degrees of your active ranges. Typically hypermobile people will be able to push much further, but I want you to stay closer to your active range instead. Then we can create strength in those ranges, and slowly start increasing your active ranges through weeks and months of training. The goal being to minimize the gap between passive and active over time.