Nothing in the nine years I've been practicing yoga has been as hard on my practice as chiropractic school. Seventh quarter was especially was hard on me, and hard on my practice. At the end of the quarter I went several weeks without so much as a surya namaskara. Now I'm trying to get back to practice. Besides the tigher hips and hamstrings, and maybe a slightly less tolerance for 10 surya namasakara that crept up while I was being lazy, the thing that prevents me from my pre-break practice habits is the wrists. It's not a pain that lasts after savasana, or even really a pain at all. But rather an ache that develops in my wrist a few asana into the primary series. When I experience this, I simply go on to finishing. In fact, instead of doing a proper bridge or upward-facing bow I will simply place a block under my pelvis and breathe for 25 breaths instead to avoid weight bearing on my wrists. What is going on?
Of all the things that yogis and non-yogis ask me about yoga, the wrists are number one on that list. Questions like: what do you do to ease the pressure on your wrists, my wrists are too bad to practice yoga, and do your wrists get messed up from yoga. All of these things and more come up. I even get questions about people wanting to do push-ups and think that the yogis have the answers.
The thing that many people don't think about is that your bones are living things. And as living things they change in response to stimuli. How often in your everyday life are you weight bearing on your wrists/hands...as much as your body weight? Not so much. In many yogasana you are supporting half to all of your weight with your arms. That's a lot for them. Bone remodels according to the stress it regularly experiences. This is why astronauts will come back to earth after living without gravity and have bone loss. It's why your bones are not perfect lines and cylinders, the muscles create stresses on the bones at different points when you're growing and the bone grows to accommodate that. This is also why weight-bearing exercise is recommended for those with, and at risk for osteoporosis, it can give the bones strength where it's needed.
Your body can change a lot in a few weeks. It takes 120 days for cortical bone to fully remodel against a new stress and about a year for the medulary bone to accomodate that same stress. A study monitoring bone strength in patients on bed-rest found that their skeleton changed it's strong parts from places like the heel to the new weight bearing places like the back of the head in a course of 17 weeks. All of this makes me think that it is likely that my body started to change during that break in my practice schedule. During that period of practically no weight bearing on my arms, I likely lost some of the strength there. I can no longer tolerate nearly 50 vinyasas in a practice. The way to get back that strength. Practice. Repeat. The science says at least 3 times a week will do you.
As a yoga teacher I think this is a valuable lesson learned. There is a reason to focus on the standing and seated asana with beginners and especially so with elderly students new to yoga. Let their bones get stronger. Encourage regular practice, at least 3x a week. Build them up from just one or two vinyasas and one short inversion. Take the pressure off the arms and let them grow gradually. Let these students know that if it hurts in their wrists, it's okay to ease up. Teach the very valuable half-sun salute as an alternative in beginners classes. Let them insert this variation as needed. Gradually increase the amount of weight bearing in the arms. In time, a hand stand and vinyasas will be much more tolerable.