I'm always looking for ways to make my Achilles a little happier. I've used Speedcross for years and that probably helps.
I grab a 40 lb kettle bell. Use 2 feet to stand up on your toes on the edge of a stair and then lower yourself with one leg. I do 20 reps for each leg of this.
Got it. I’m allowed to go up on one foot but I had to start by doing it with two feet. I’m not allowed to drop off a step because my problem is at the tendon insertion.