One of my main principles of focus for strength and movement is Range of Motion. Your body is designed in a specific way for you to function healthy, freely, and without pain, in life. Over time without regular dynamic activity and constant static positioning (sitting, sleeping), our range of motion decreases as our muscle mass and memory decline. Also excessive repetitive movement such as cycling and running, tend to hold joints in specific patterns and limit range of motion as well. So no matter what your conditioning level is, it's always important to devote time and energy to your body's flexibility in order to live with ease and comfort throughout life.
Here's a basic stretch routine. I love to stretch out after a nice intense workout. My muscles are warm and heated and I'm ready to relax and focus inward on my breath and flexibility. Practice regularly :)