Please excuse if this has shades of the "snob" factor, but I practiced and then taught Pilates from 1978 until 1989, and also practiced various other specialized training methods, such as Rommet Floor Barre, Alexander Technique, Feldenkrais, and various methods of strength training, ie, machines, free weights, isokinetic resistance, and pool training. IMO, if you limit yourself to one type of training, such as Pilates, your body adapts so that certain muscle groups become developed and others don't. There is no one kind of training that is the magic bullet of training. Pilates has a lot of advantages, it's not particularly good for strengthening the back and abdominals because it doesn't provide enouogh resistance plus the resistance for the abdominals tends to be isometric, which doesn't translate to what a skater needs.
Also, Sasha may have changed to swimming to take some of the pressure off her back while it's healing. Not knowing the exact nature of her reinjury, I can only speculate, but I do know that pool work is usually the first type of training recommended after a lot of injuries, but especially back injuries.
I do recall reading Robin Wagner say last spring that she would have Sasha doing quads and even quints by mid-summer. Although I have no idea if Sasha took an extended period of time off or exactly what her training schedule was, wasn't she touring with COI from June through the beginning of August or thereabouts? I know show skating only requires a few triples, but it's not exactly time off. Anyway, by my way of thinking, concentrating on quads even without much time off for a skater who has a history of serious back injury and just recently made some improvements in her triples is asking for trouble.
If 4/3, 3/3/3, etc. are expected as part of champion skaters' jump repertoires with virtually year-round training, IMO, they and their coaches are going to have to take a whole new approach to training. Because no single method of training is going to keep a skater in peak condition without resulting in overtraining, a method called "training periodization" is what I'd like to see more skaters use. Without going into detail, training periodization is a method whereby different methods of training are used throughout the year so that the body and mind neither become overtrained nor stale, including periods where the skater doesn't even skate at all, but stays in shape by doing other activities. Unfortunately, the demand for jumps has increased so quickly that coaches and skaters are basically guessing at what to do.
BTW, this goes for all skaters if they want to have a competitive career that lasts more than two or three seasons. Also, unless you've treated a lot of back patients or been through it, you can't imagine how strong and invincible you can feel for years only to one day do your regular training and a few hours later feel more back pain than you ever thought possible

, which makes sense given how chuggy-jam the spine is with muscle, nerve, tendon, nerve, ligament, nerve, bone, and nerve, nerve, nerve. The real spine looks so unlike those clean plastic models in doctors' offices, it's no wonder people are so confused as to what to do when they have a back injury

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Good luck to all the skaters pushing the inside of the jump envelope. IMO, these next 10 years of jump evolution are going to be tough and frustrating :banging:.
Rgirl