There is an art to years long practice of yoga asana. It's finding the balance of breath and movement in ways that stretch, open, strengthen and renew without causing unintended injury.
As with any exercise there run risks of injuries. When practiced over time there is a particular type of injury known as repetitive use injury. An example of a common known repetitive use injury is carpel tunnel syndrome. When we repeat the same motions time and again there is a risk of aggravating tendons, ligaments, etc.
I know this first hand! After years of a strong practice I began to feel a constant sore hamstring insertion point high in the back of my left leg. I began wondering if I pulled something? I couldn't remember ever feeling a moment where I thought "OH that's gonna leave a mark!" In other words, no noticeable instant injury to my hamstring. Through investigation and research I learned that I likely had what's called a repetitive use injury. All of my years of forward folds both standing and seated somehow over time aggravated the insertion point interestingly just on my left leg. At this time, I had developed really long hamstrings! Able to touch the floor with flat palms and straight legs no problem! Yay! ...right?
When we practice length or flexibility there is also a need for the strength component. Holding integrity within the joints at times is a way to use strength while working the length (perhaps another blog on this topic soon!). Another way that is more instantly (for most) applicable is not always going as deep as one is able in the pose. Just because we can does not mean we always should.
To help heal this very aggravating deep tissue injury I began to fold with less length and depth, not stretching as far as I could go. I keep a soft bend to my knees rather than straighten my legs in my forward fold. I do this more often than not and only really extend to my full flexibility point after I know I'm very warmed up and then just for a couple of times during my practice verses every time I fold. My left hamstring insertion point is now much happier!
A lot of our most valuable lessons are learned from personal experience! However, I write this in hopes that it may help some of you who plan to practice yoga for life. You don't always have to go as deep as you can! Be good with half way for several times during a practice, be good with half way a lot of the time in every practice! After all, our yoga asana is to benefit our wholeness. Wearing ourselves to an extreme point limits our ability to carry on in the healthiest ways possible. This is a lesson I feel we westerners learn time and again. We often want to be the best and push hard. Nothing wrong with being the best you can desire. It does though often need to be tempered with patience, slow and steady work and Not pushing hard. Being consistent and not insistent.
I like to practice what I call sustainable yoga. Yoga for life! When you go to any class give all poses and lengths of time the teacher calls for a try. And yet, listen to your body and be unafraid to take breaks, ease off and not press too far or too hard. You will be the expert in this knowledge as it is your body! Your teacher can't know because they don't feel what you feel.
This is yet just one of the amazing tools we can learn with our yoga practice that then translate to other areas in our daily lives, including our mental, emotional and spiritual bodies. Steady and consistent work and yet not pushing to far or too hard.