Flexibility is one of those aspects of your training that you oversee when you are a beginner. You know it is there, you know it is important, you know you are not very good at it, but you look to the other way. Finally you reach a point when you have to train it, specially when it works for a trick or exercise that you want to achieve.
Of course the ideal would be that you train it from the beginning, because it will keep you from getting injured and you wont have mobility problems when you want to do advanced movements.
When we think about flexibility we normally are thinking about pasive flexibility, where you use gravity or any external help to maintain the strech.
But you can also work in an active way, where you use your own muscles to extend or flex your joint to the max.
The ideal would be to use both types. Pasive flexibility is better to improve your range of movement, but active flexibility will give you mobility, that will allow you to use your flexibility consciously in your tricks or exercises.
For example in an straddle planche (legs spread), you use the muscles around your waist and hips to open your legs to the max, so it is active flexibility, and the better trained you have it, the more you can spread your legs, which will make your planche easier to do.
When we train static flexibility, we stay in one stretch, but when we train dynamic flexibility, you stretch and the relax, doing repetitions.
It is usually recommended to do dynamic flexibility before your regular training, and static after your training (leaving around 30 minutes for you to cool down). If one day you are training only flexibility, it is better to do static.
1º Use it as a warm up. Personally I always do flexibility before training, as part of my warm up.
Using the exercises we are going to see next, I do 3 short sets of each one (6 seconds each set). I try to avoid longer stretches because it seems that they make you lose some strength in the moment.
2º Some days do it after your regular training. When you have some spare time, wait 20 or 30 minutes after you finish your regular routine and then do flexbility. Use also the exercises that we are going to see next and do 4 sets of 35" each one.
3º Some days train only flexibility. When you have a rest day, or maybe you have your calluses hurting, use that day to train only flexibility, do 4 sets of 45" of each exercise.
As a reference to know how much to strech each joint, my recommendation is to always train without pain. Imagine a pain scale from 1 to 10, you should never go past 3 or 4. If it hurts, go back a little and hold where it is pain free.
Very useful for a lot of movements and tricks. Having a good shoulder extension will allow you to do: full range dips, muscle up, skin the cat, back lever, hefesto, korean dips and some freestyle tricks.
Very effective for handstand mainly.
They make you open your legs to the max. Very useful for straddle planche and Maltese planche, the more you can open your legs, the easier those exercises will be.
With this exercises you mobilize all the back part of our body: calves, femoral biceps, glutes, back... And it is really useful for exercises like leg raises, V sit, press to handstand and some freestyle tricks.
When I started training I was very rigid, not flexible at all, and I think that working on my flexibility has been very important, first to avoid injuries, and also to be able to do a lot of tricks.
My recommendation is that you use flexibility exercises in short sets in your warm up, because it won't take you more than 5 minutes and with time you will feel the difference. In the warm up routine you have here in Calisteniapp, those exercises are included you you can follow that.
Also if you have a rest day because you have trained hard or your calluses hurt do a full session of flexibility, with the exercises we saw but in long sets and it will make a great difference.