[4] Nadal- Loss of footspeed - Explosive first step/acceleration -Agility -Stamina - Shot tolerence Diagnosis- Sarcopenia(muscle wasting due to aging)
I would say nadal is the most declined out of the rest of the big 4 because of his loss of speed is the most evident from looking at old videos of him. His physicality and what he could do to outlast opponents is also gone and he has offset this by playing super aggressive. In recent times he has become increasingly injure prone due to physical style and aging. Remarkably he still managed to accomplish alot since his sharp decline this is a result of how strong the rest of his game is. Particularly his forehand and his lion heart to keep fighting. With the addition of Carlos Moya who has strengthened his backhand.
--------------------------------------------------------------------- [3] Federer - Loss of footspeed - Explosive first step/acceleration -Agility - Footwork due to decline in agility(see above) -Stamina -Mental fragileness Diagnosis- Sarcopenia(muscle wasting due to aging) ----------------------------------------------------------------- Although retired now we can still talk about him and what led to his decline. As stated across MTF the major decline happened on post AO 2010 where his movement sharply declined, federer became olderer. He had trouble covering the court as players started to target his backhand to get a weak reply and send a hard shot to the forehand side open court where federer was unable to cover anymore. Through the mid 2010s he made some adjustments to the decline by getting a bigger racket and unlocking his Neo backhand which has given him some amazing results at the twilight of his career.
[2] Murray - Loss of footspeed - Explosive first step/acceleration --Agility -Stamina Diagnosis- Sarcopenia(muscle wasting due to aging) - Metal Hip
Murray's decline happened obviously from the well documented hip injury. His speed and agility around the court is nowhere near his prime due to the hip surgery and the Sarcopenia , muscle wasting obviously going to happen with a long layoff and aging. He has tried to implement an aggressive game to offset his decline but he has struggled due to never really having a killer forehand. He has managed to remarkably improve his fitness recently and has managed to recover a good fraction of what his stamina used to be. His anticipation ability one of the prominent feature in his prime is still in tact and his still able to utilize this to predict opponent shots and counter them accordingly. He maybe able to post some decent results in 2023 with his improved fitness.
---------------------------------------------- [1] Djokovic - Shot tolerance - Stamina -Loss in power
Diagnosis - Decline in short term lung capacity is pretty evident now with his loss in shot tolerance, functional decline to be able to take in a lower amount of oxygen with the decline of cardio and lung volume. The loss in power is evident from 2017-2020 seasons as he is struggling to hit through slower surfaces like clay and the US open which has being his poorest results in recent memory, this maybe due to the elbow injury causing his strokes to be less penetrating. I would say although djoker has done well to take care of his lower body by stretching regularly as he still able to retain relatively the same footspeed as his prime years in contrast to the rest of the big 4 , his upper body however has evidently declined, this maybe due to Sarcopenia in the upper body as well as loss in bone density because he never really had big muscles to begin with, as well as again with the elbow injury causing him to have weakened strength.