In this example from the 2005 World Championships in Montreal, you can see Kirsty Coventry completing her midway turn in the 200IM. One key thing to note are how well she spots the wall and finishes on a full stroke. Also she turns to almost 90 degrees so her shoulders are vertical before she touches, then as soon as the touch is made carried out a conventional forwards tumble turn. The most critical thing is not to go past the 90 degree position before you touch the wall. This turn is high risk, because at speed it can look like you are on your front before you turn (you might even think that Kirsty is on her front watching in super slow motion), and is still rare even at international level; the adjacent lanes use a conventional push turn. It is the turn used by Michael Phelps however.