I saw this article here about yoga teachers, especially those who have taught for many years, & their own practice.
I have been living the yoga life for decades now, & along the way, have learnt a thing or two. I have seen yoga teachers shrink in height as they get older, & I am sure that this is due, not only to their diet, but also to their non-practice of physical yoga. When I hear someone say that they "do yoga all day long", I know that this is supposed to mean that the teacher is immersed in witnessing/drastha bhav, detachment/vairagya, constant practice with this/abhyasa. But it is not always the case.
Sure, one can float around in lovely states of mind, from the energy generated by teaching classes, & of course, we are meant to develop drastha, vairagya, abhyasa, as a direct result from our own practice. Note, that it is from our own practice, that the fruits of yoga emerge within us & our lives, & it is our own practice which not only maintains them but also keeps them developing. Teaching alone will not do this. And if we are relying on an outside (yet, internal) source of energy & consciousness during our teaching...this is transitory, & can end at any time, whereas the fruits of one's own practice, remain.
The article that I read, talked about how the yoga teacher's practice does change as one gets older, & that they should not try to keep up with a 20 year old whom they are teaching. Which, of course, is quite logical. You can bet that most 20 year olds are not going to be turning up every day for 60 - 90 minutes of hard asanas. And neither should the yoga teacher. Practising hard yoga every day can be stressful & can cause inflammation, bad back, or joint problems, in some people. But, without the strong poses to build strength, the body can deteriorate.
Not all of the poses build strength. The more strenuous asanas such as warriors, trikonasanas (triangle), wide legged forward bend, planks, chaturanga (like an elevated push up...the downward phase), down dog/mountain, updog/cobra, locust with head & legs raised, chair pose, arm balances...they do indeed all build strength. Especially when held for 5-8 deep breaths. Body builders do not do strength poses every day. They often do strength training on alternate days, giving the muscles time to repair, & whilst yoga purists might disagree, I think that this is excellent. If you are holding these strengthening poses & are time crunched...think about doing them 2 -3 times a week, as in a series. Yoga teachers do need to practice what they preach, & if we are teaching these poses, it will not hurt to do them ourselves. But it need not be everyday. Strength training of any sort is excellent for bone health, & for muscle tone.
When I 1st started yoga, we didn't do down nor up, dog, warriors, chaturanga, planks, etc, as difficult poses which we held. And I do know that yoga is not about the body beautiful. And I am quite familiar with the frustration that we older yoga teachers can have, when we know that people come to yoga for their fitness. Yoga does give fitness, definitely. But it is done through just doing the poses, regularly, without holding poses. Just doing them.
I have seen older yoga teachers get unwell from practising too strenuous yoga everyday, & others losing muscle & bone thickness from just doing a bit of wimpy stuff here & there. For most of us teachers, time & space for ourselves is difficult, so I recommend doing a basic everyday routine for suppleness & also for hormonal health. Do the harder poses a few times a week. If you do some morning sun salutes, you can do just a few with excellent posture, or do a few more, but a wee bit faster, without being so fussy about correct form. Of course you can do more asanas than this...but make it doable & easy to maintain.
Go upside down in the evening...1/2 shoulderstand is excellent. Do a few poses in a restorative way, on the floor.
It's not just the physical that we need to do. Do some pranayama. To do advanced pranayamas, & a lot of it, regularly, seems to produce another sort of imbalance, different from not doing any poses. I have seen a few older people get a bit batty, by just emphasising advanced pranayama with mudras, without doing much in the way of asanas. And too much meditation....(I should be so lucky.....) ...a yoga teacher of long duration doesn't require much effort to enter into a meditative state quite quickly. But we do need to balance it with some physical activity.
I also do a couple of sessions a week, of joint loosening exercises. My 1st yoga teacher was 78 when I met him. No-one in the class had his stamina nor suppleness. He did the same set of flexibility movements, every morning. Not the pawanmuktasana series, it is a bit different. I often think that these sort of movements are like a "missing link" with asanas. If you do them a few times a week, your whole body will respond quite dramatically & you won't have to try so hard with the poses.
Teaching a lot of yoga, & maintaining your own wellbeing at the same time, is a question of balance. But above all, it should suit you & your life.