@skaarperformance: This has been the most effective exercise I’ve seen for Achilles issues recently. I’ve had people basically get rid of tendinosis with plans based around these and plenty of tendinopathy successes. There may be reasons why a 3-5 second higher force iso would be “more” effective, and while I do use those, I think the instant feedback of whether or not you can hold the weight and the contraction you get in your calf with these make a huge difference. I’ve been using them for probably over 2 years now and haven’t found anything better