Why stretching shouldn't feel painful?

Pain is a warning signal that our muscles may tear if stretched too far. When we start to feel pain, the body’s natural protective mechanism will contract the muscles to prevent them from being stretched further. If you try to force the stretch further, the body will keep fighting back to contract the muscles. This is a counter- productive approach to improving your flexibility.
For effective stretching, less is more and patience is key.

When you stretch, you simply need to come to a position where you feel a slight stretch in your muscles. This position will provide a signal for your mind to notice where the tight muscles are. When your mind notices, you simply breath and these muscles will naturally relax.

When these muscles are able relax, then they can stretch further with out causing pain. They no longer hold you back, so you’ll naturally be able to go deeper into the stretch without feeling pain. Then you come to a deeper position where again you feel just a slight stretch. It’s the same amount of stretch that you feel, but now you are engaging deeper layer of muscles. Your mind notices these tight muscles it hasn’t noticed before. You breath and relax these newly discovered muscles, then move naturally into another deeper position. In such cycles, you can go really deep into your stretch while staying very relaxed.

​Like peeling an onion, you relax the muscles one layer at a time, patiently. This way you’ll use less effort, feel no pain, but reap more results. The key is not forcing.