So, how do you undulate well? Undulating, meaning a small wave-like motion, essentially, you’re going to be looking at your body as a seesaw. When one part of the body comes up the other part of the body goes down. Short-axis strokes, as we already said, that split or that axis that you’re rotating around is at the hips, it’s kind of towards the top of the hip towards the iliac crest. So, if your legs are kicking down your body is coming up and if your legs are coming up your body’s going down. And I picked these two pictures because they’re a great depiction of the transition points between undulating, so you have this girl’s head far out of the water, which means your hips are at the lowest point of the stroke. And then you have this girl who’s dropping the head down, and you can see that her hips are higher than her head in this photo, so she’s at the opposite transition point compared to the girl over here. The name of the game in Butterfly is when you undulate in fly you want to keep making sure that you’re moving forward. So, this position, you can see is less of an extreme angle, as far as if I were to draw a line for this girl’s body versus this girl’s body is, this one is a steeper angle compared to this one. So, if, as you get tired, the goal is to make sure that your angle here is always followed by a nice follow-through. So you really want to make sure that no matter how far you come up after you are when you’re breathing and fly that you can get the body back down to a decent body line because everyone eventually gets tired and fly, and I call that position when your heads up and your hips are sinking, even after you’ve taken a breath, you just don’t recover and get the head down far enough, but supine position, because if you look at all this water that’s running into her chest and her body down to her hips is a very very very high drag position, whereas this position yeah there’s a little bit of water hitting her upper back and all that jazz, but the majority of her body motion is still pushing her forward versus there being a lot of resistance as she’s trying to go forward as well. So the name of the game is how long can you avoid the snowplow position and then when you get there, how good can you recover from it each time after you go through your undulation, because it’s easy to come up, it’s hard to go down as you get tired.