Hi Robin and welcome to the Forum. While this is a Yin Yoga forum, and your question revolves around how to develop more yang stamina, it is a good question, so I will take a stab at offering some thoughts.
Like you, I too notice that I am getting older! I don’t have the abilities to do what I once did with ease, but that doesn’t mean we can’t maintain a good deal of stamina and endurance as we gracefully age. I believe there are 3 keys to growing old fit and hale: flexibility, strength and endurance. Yin Yoga certainly is my key to maintaining flexibility, but I also rely on resistance training to maintain my strength and other aerobic activities to maintain stamina.
These days I rely both on my yang yoga practice and weight training to maintain strength. In my yang practice I work with down dog, planks, pushups and handstands to build upper body strength but I also swing kettle bells. As we work with weights (both our body weight and free weights) our muscles release various hormones and chemical messengers, like growth hormones, that help all our tissues stay young and vibrant. We need weight training, especially in the upper body, as we age. It also helps the heart.
For stamina, I do sprints as well as my active vinyasas yoga practice. I love the way Dr John Douillard explains the benefits of sprinting in his video
Be Calm, Fit and Lose Weight in 12 Minutes. He notes that it is more natural for us to sprint than to run long distances at a time. His method is to sprint (or jog, or just walk fast --- depending on what you can do) for 1 minute maximum, then walk for 2 minutes, then repeat this 3 more times. That will be 4 sprints in 12 minutes. It certainly works for me, and you might find it magic too.
Good luck!
Bernie
