One hand backhand is probably the most difficult shot to understand besides serve because the entry threshold is so high.
The force isn't shoulder, isn't chest, isn't arm. The force is actually hips, and the muscle right on the top of thigh and that's it.
To understand how to use it takes a lot of understanding of what doesn't work.
I think I have mastered it, it feels so good hitting like this
I look at high speed videos of ATP players and Justine Henin for the 1HBH. I have presented a lot of evidence here and identified many other sub-motions used by the majority of current 1HBHs in the ATP. You can look at the videos I showed and described and disagree or agree and point out in the videos, what you see.
I don't say where the forces come from, all the body parts involved, unless there is evidence, as there is with the '
chest press'. The upper arm (Humerus) initially accelerates in sync with the chest or a line between the 2 shoulders.
'chest press'
There are forces there and at many other places. There are also forces in the trunk that I cannot see well in videos. I just say "twist" and "untwist". And forces to the hip joints from the leg bones. And forces in the length of the legs in muscles to push at the hip joints. Forces are at many joints, there are 600 muscles in the body and a few of them can be seen doing their thing, and many others cannot be easily seen.
Separation deals with the trunk twisting and untwisting and its forces and the
stretch shorten cycle. If you look at a tennis tournament, you will see that the hips turn some and the line between the 2 shoulders turns more and faster, that's
separation. It's untwisting of the trunk. When the first phase happens, the shoulder mass and upper arm are accelerated before the shoulder joint itself has been used, to add acceleration to the upper arm, two phase stroke....
If you look at Federer's 1HBH analysis, he does not use the
chest press because you can see air between his upper arm and chest at a much earlier time. Posted. F. Lopez is the same. When I first viewed Lopez, I was surprised that he hit more backhand slices than drives. This was well over 5 years ago and he may have changed more recently.
If the uppermost body were accelerated enough & longer by the trunk untwisting, the upper arm would still be pressed by the chest.
In fact, the forehand also uses the uppermost body forces first rather than the shoulder joint, which is used later before impact. Djokovic shows 2 phases in his forehand drive if you look at his video from the side. Consider the line between his 2 shoulders and the line of the upper arm at his shoulder joint and watch what starts it forward and later the shoulder joint motion. Both 1HBH drives and forehand drives use a two phase use of muscles to accelerate the racket mainly 1) the trunk untwisting (plus hip turn, plus legs pushing) and then 2) the shoulder joint is used.
To single frame in Youtube, stop video, go full screen, and use the
period & comma keys. A trick is to use the
period and
comma keys held briefly, alternately, to go forward and back repeatedly. It sometimes shows things that you can miss, like the direction of travel of hand, racket and stuck ball. Especially good from behind a server.
The running foot can be planted and that can be used to suddenly slow/stop one side of the body and cause the hips to rapidly turn - not much muscle use....... It seems reasonable if your are observing the videos presented as you read each point of what I said above. Gasquet ran and appeared to plant his foot for body rotation for a 1HBH.
You can think about what I said above and check it out in high speed videos. Criticize each video observation.