This sequence is also taken from a video produced by Speedo, the swimmer is Jessica Hardy, US Olympian and gold medalist in the 4 x 100 Medley relay.
1-) On the first picture we see the starting position for every stroke, notice the arms stretched out till the elbows are locked, and the feet together. The whole body is lined up right under the surface in a horizontal line; remember you want to move forwards not downwards.
2-) With the feet still together you initiate the out sweep with the hands. Notice the head position, still looking down, it is important not to initiate the breathing at this point, you are squeezing through the “whole” being opened up by your arms. Also notice the arms straightened out, there is no bend in the elbow, they are locked and as straight as they could be.
3-) This is the catch. Just as in every other stroke the catch is done by bending the elbow. Notice how close the elbows are to the surface. The angle created at the elbow should be about 90 degrees, not much wider and definitely not less, don’t bring your hands inside in between your elbows and your shoulder. With the catch you can see the head is starting to come up, notice how she is squeezing her abs (you can see it through her suit!) and she is using her core (abs and back) to help get that head up.
4-) Number 4 is a sequence of pictures meant to show the pull. First of all notice how the elbows always stay right under the surface. Use the forearm and hands as a paddle and squeeze in right under the surface, once your arms are close to each other you can start to drive them forwards to extend. Notice also how the legs have started to bend through the pull, as you squeeze in and get ready to extend your arms, your legs are starting to bend.
5-) This picture shows the elbows under the shoulders. Notice how throughout the pull (seen on picture 4) the elbows never went behind the shoulder, the most they went back is right under the shoulder. Some swimmers do end up getting their elbows behind their shoulders, but it is much better to just think about keeping them under the shoulder and go from there.
6-) Here we can see the extension of the arms. Right under the surface, the legs are now bent almost to its max point of flexion.
7,8, & 9 -) On these pictures we see the kick getting set up as the pull is being executed. They can be cross-referenced as follows: Pictures 7 and 8 correspond to the same moment as the sequence on 4. Picture 9 corresponds to picture 6. Notice on 9 how high the heels come up, and how close they are to the hips. Also notice through 7 & 8 how the toes are pointing back, and the sole of the feet is facing up. On 9 you can see that the toes are starting to point to the side. The toes turn to the side when the legs are at the max point of flexion.
10-) On picture 10 you see now the toes pointing sideways, and the soles pushing facing the end of the pool as they push the water back.
11-) This picture is meant to show how the knees always stay shoulder width apart. If you go back to all the previous pictures you can see that the knees never popped outside the body width.
12-) back to the starting position, arms extended, head facing down and feet together.
Note: you can’t see it too clearly in this sequence of pictures, but remember that the head is always in line with the spine, don’t bend your neck!