My little and now old girl cat, Binnie, can still jump, when she puts her mind to it. However, it's not that far. She has lost a lot of her jumping power and walks a little stiffly - all to be expected as she is about 14 years old.
As jumping is more difficult for her she has to think about a jump more. She also has to concentrate more and this shows. She sways her head from side to side a lot and for longer before making a jump.
She moves her head from side to side to use her binocular vision to maximum effect in judging the distance accurately. When the head is moved the eyes see the target object from a different angle allowing the brain to better compute the distance and the force required to jump to the exact spot.
For a predator inch perfect precision in required as she is in fact pouncing on prey. The African Serval is particularly adept at this as she leaps into the air and drops onto small prey such as rodents, stunning them on impact with her front paws.
For Binnie, life is less exciting but instinctively she measures the distance with the same radar like precision. That's me girl Binnie you show 'em how clever you are...
The cat in the top photograph is not mine but a cat about to jump - reproduced under creative commons (Flickr) copyright danilou
The picture on the right is my Binnie taken about 5 years ago.>>>>>
This is her more usual position :)