The Ready State Virtual Mobility Coach is like having a virtual Kelly Starrett in your pocket.
One cause or impacting factor can be the shoes you are wearing.
If the heel is elevated this shortens the heel cord.
See if any of these help.
Why Put Your Kid at A Movement Disadvantage?
Introducing the Bone Saw: Calf Smash Redux
Episode 350: Tack And Floss: Heel Cord Edition
Episode 337: Long Ruck Feet Or Ultra Marathon Feet?
Episode 319: Protect Those Heel Cords Man!
Episode 167: Unglue That Heel Cord
Episode 30: Partner Heelcords–Safeword? Part 1
Episode 30: Partner Heelcords–Safeword? Part 2