No kick

I hate to say this, but... Without increasing ankle flexibility......... Well, I for one am glad you did! Not sure why you said you hated to say it (other than repeating the other thread, but as someone who wasn't around back then, I like seeing things that may be "old news" to some folks. That said, I noticed that when I went from lap swimming to following the posted workouts, swimming with fins (UDK sets) KILLED my ankles. Part of that was kicking with my legs, but another part was lack of ankle flexibility. Granted, I'm an odd case in that I quit swimming for exercise over 20 years ago when I broke my ankle (took me 12 years to have it surgically repaired) because I lost all flexibility in it, and the pain was overbearing. It is still not quite as flexible as the other, but it is much better. I mention all this to say that I honestly believe that doing the UDK sets with fins has been a big component in increasing my ankle flexibility. I'll let you more knowledgeable people opine on my anecdote, but since some have argued against fins, I thought I'd bring up a counterpoint. Have you seen anyone in Olympic 10 km open water swimming without a strong kick? Actually, many of the distance swimmers like Ledecky and Yang use very little kick for the first 1/2 to 2/3rds of the events. I believe it is because kicking uses a disproportionate amount of oxygen, relative to benefit. Not a problem for short races, but a notable one for purely aerobic events.

I hate to say this, but... Without increasing ankle flexibility......... Well, I for one am glad you did! Not sure why you said you hated to say it (other than repeating the other thread, but as someone who wasn't around back then, I like seeing things that may be "old news" to some folks. That said, I noticed that when I went from lap swimming to following the posted workouts, swimming with fins (UDK sets) KILLED my ankles. Part of that was kicking with my legs, but another part was lack of ankle flexibility. Granted, I'm an odd case in that I quit swimming for exercise over 20 years ago when I broke my ankle (took me 12 years to have it surgically repaired) because I lost all flexibility in it, and the pain was overbearing. It is still not quite as flexible as the other, but it is much better. I mention all this to say that I honestly believe that doing the UDK sets with fins has been a big component in increasing my ankle flexibility. I'll let you more knowledgeable people opine on my anecdote, but since some have argued against fins, I thought I'd bring up a counterpoint. Have you seen anyone in Olympic 10 km open water swimming without a strong kick? Actually, many of the distance swimmers like Ledecky and Yang use very little kick for the first 1/2 to 2/3rds of the events. I believe it is because kicking uses a disproportionate amount of oxygen, relative to benefit. Not a problem for short races, but a notable one for purely aerobic events.