Some testimonies I've found so far:
-Programdude, who gained 3 inches with Paley in 2014, wrote in 2019 "As for sports, personally I've got to advise against LL if you have serious sports interest. Although I might currently be biased since I need to get the irritating hardware out of my leg from my fracture, I can say with confidence that if I had been serious about sports, my running/ movements would be a good deal away from 100%."
http://www.limblengtheningforum.com/index.php?topic=285.31-pharmacology, a professional MMA fighter and former collegiate wrestler, posted a few times in 2022 during his lengthening, unknown doctor, and then disappeared without reporting on the results.
http://www.limblengtheningforum.com/index.php?action=profile;area=showposts;u=11132-C4LLvet is more optimistic: "I did 8 cm lengthening in my femurs with Stryde nail back in 2019. I can tell you that, within the 1st year into recovery (so by the end of 2020), I was able to fully run/ sprint. I was not as fast of a runner as I had been pre-surgery, but I also did not actively train/ work hard to regain this pre-surgery speed. Frankly, I didn't care that I couldn't run quite as quickly (the height gain was much more valuable for me).
However, I could and did engage in athletic activities (running, basketball, etc) and participate in them to about the same extent as I had previously. And I found that if I trained hard at it, my gains improved.
So long story short, I think it would be difficult (perhaps impossible) to become a professional athlete after a surgery like this. But you could regain your prior levels of physical conditioning with time, energy, and determination. I'm thinking 2 years post-surgery, you could be very close to your athleticism prior to surgery, even if you lengthen a lot (like I did). It is not easy, but an achievable goal."
http://www.limblengtheningforum.com/index.php?topic=84854.0-In 2014 Sweden said "You won't recover fully.
You can do sports some days but never like before."
http://www.limblengtheningforum.com/index.php?topic=285.0Interestingly, ReadRothbard responded "Keep in mind that last we heard from Sweden, he was going to a national full-contact martial arts championship. I would personally consider that fully recovered."
By 2022, Sweden had made a full recovery minus jumping ability:
"I’m 40+ years old now and I qualified to compete at the highest level in Taekwondo.
Yes I’m proud of my achievement!
Knees hurt some days and some days they don’t. I can walk and run and jump(but not as high as before).
Last year I broke my knee from doing a jump kick and it hurt like hell.
6 months later I won the championship. It was a pain, but I’m still competitive.
I can’t recommend doing more than 5cm and definitely not passing 6cm. The down time is too much from doing more cm.
I was a pro athlete when I went to India and it took me 6 loooong years to get my professional athlete card back again. Some months I trained 3 times/day - and having a full time job."
http://www.limblengtheningforum.com/index.php?action=profile;area=showposts;u=7Sweden agrees with this comment by LLPrime3: "That is why the response "You won't reach your pre LL atheltic level after LL" is a message from average people directed to other average people who check out from the responsibility to recover fully and beyond by labeling it as an impossiblity. You should know yourself in which category you fall."
-MediumDrinkofWater had lengthening in 2007 at the Beijing Institute of External Fixation and wrote in 2014 "I consider myself pretty much fully recovered. I can walk normally and run almost as fast as I used to be able to, but my balance and agility aren't what they used to be. The longer legs are just harder to move quickly.
I'm never was an athlete, so I don't know about playing sports after LL. Your performance would be reduced, but I'm not sure by how much."
http://www.limblengtheningforum.com/index.php?topic=285.0-Smallguy claimed in 2014 to be doing MMA, but not clear when he had his lengthening.
http://www.limblengtheningforum.com/index.php?topic=285.0