"The key to the glide is really quite simple.
When looking from the side or the rear, the shot must stay in a straight path from the low point to the high point.
This sounds simple, but that is the key.
The body must move around the shot to allow it to stay in line.
First you pull it to middle, then you move around shot to get behind it, and then you push it to finish.
Don't move the shot around you, you move around the shot."
Ulf Timmerman