(I apologize to the vegetarians and vegans in advance)
Have you heard of the ITB (iliotibial band)?
It’s the tough tendinous/fascial aspect of the lateral/outside of the thighs/quads that can become tightened with internal rotation of the hip and knee.
Have you heard of plantar fasciitis?
It’s the tough tendinous/fascial aspect of the bottom of the feet that can become inflamed when the area becomes tightened by gastrocnemius/calf muscles that are flexed/constricted too frequently without rest.
Note the white is fascia connecting the tendons from the muscles to the bones.
These are only two aspects and areas of the continuous connective tissue called fascia.
The superficial or external fascia is essential for movement of the arms, legs, neck, fingers, toes, all of the extremities and the joints that assist with ROM and movement. This is essential to running, jumping, walking, lifting weights in a gym, riding a horse, playing piano, crocheting, building instruments, everything. If there isn’t fluid movement in the extremities, you can’t move very well. Fascia assists with movements, and tight, unhealthy fascia restricts flexibility of the joints and muscles throughout these movements. Putting it another way, if your connective tissue onesie is 4 sizes too small, you won’t be able to move very well, if at all!