Incidentally, Dimitrov ran a personal record [time not known] and received praise from the Bulgarian Federation for the effort. Clearly, Dimitrov's shape is pretty good and he is currently working on some new routines and balancing those out with heavy training sessions.
The 28-year-old Bulgarian had a strong finish to the 2019 season - climbing from No. 78 in August to No. 20 at the end of the season, mostly due to the US Open result where he beat Roger Federer, only to go down to Medvedev in the Semi-Finals.
Dimitrov was ranked as high as No. 3 in the world in 2017.
He will kick-off the new season at the ATP Cup in January in Australia. He'll be the leader for the Bulgarian team in the first edition of the new competition. Bulgaria is drawn in group C with Belgium, Great Britain and Moldova. Sydney will be their home in the group-phase.
https://twitter.com/GrigorDimitrov/status/1169231377331642368