So, the differences are compared to Freestyle rotation is that during Freestyle rotation, you’re contracting your pecs your shoulders and your chest muscles, so basically everything on the front side of your body. While you’re elongating you’re stretching your back muscles, but in Backstroke, it’s obviously opposite because you flipped a swimmer on the back, so you’re going to be elongating the pecs shoulders and chest muscles while contracting the back muscles to get the hand through that pull. The main, main point of this is that your scapula, that nice little weight boat on your back which you can see down here in the diagram where those red lines are gets in the way of your ability to really actually pull Well, and that’s just anatomically we all have scapula, so we can’t just stick our arms straight behind our back, it doesn’t come out straight whereas we can stick our arm straight in front of our body and not have that rigidity or constriction essentially from the scapula bone getting in the way. So, with that because you have a scapula, and we all do, you have to rotate more than you do in Freestyle, to actually clear the water. Why, because if you go ahead and try to stick your arm out behind you as much as you can. Okay, there’s a restriction where the hand will actually be able to go straight back out of your back which is due to your scapula. So if you think about that, if we were to just swim Backstroke without rotating and pull down, you would pull down with about half of the hand above the surface of the water and half the hand below the surface of the water which is essentially skimming. And as we’ve talked about in every stroke, it’s the amount of water or leverage you can get on the water to move yourself. And so if you’re not really pushing against any water or you’re pushing half water, half air, you’re not really going anywhere. So that extra rotation ensures that the hand and arm itself gets under the water to actually be able to pull water.