These fins are described by TYR as “intermediate” in terms of length and flexibility and I have to agree. They are nicely balanced in that they work your legs without sacrificing technique. I found they encouraged me to kick from the hip with flexible knees and ankles. For fly kick, I found you can take the lazy option of flicking your feet and relaxing your core to allow your body to follow through, thus not working your upper legs or core as much. In terms of helping with my technique for flutter/frontcrawl kick, I found that I could gauge my technique depending on what parts of the leg were being worked and incorrect technique (such as kicking from the knees) resulted in a loss of power. It was almost as if the stiffness was forcing my kick into the correct technique.
For anaerobic sprint sets these kicks were great for speed and for working my legs to exhaustion, they are definitely the fastest pair of fins that I have. However, it did take a few goes before I was able to get used to them for sprint kick sets and I’m still not too happy with the tempo I achieve. I would prefer to get a higher one to better match my sprint kick without fins, but this seems to be the payoff for speed and it really helps to burn the muscles, which is my goal for anaerobic sets so I guess it balances out.
When I tried sprinting full stroke with these fins on I found it very difficult to get my balance and my arms in sync. I know it’s a difficult thing to do regardless when wearing fins, but my arms were trying to go all out in terms of stroke rate while my legs weren’t getting close to my kick tempo for sprinting. In reality, this isn’t a huge issue, most people (including myself) will probably use these for support when doing drills or to build/improve their kick.
The only real downside I find with these fins is that they were very tough on my joints the first few times I did sprint kick sets and it was tempting to compensate by allowing my technique to lax a little. However I didn’t find this the last time I did one of these sets so either I’m getting used to them or there were some small flaws in my technique that have fixed themselves. – Mike