Im very satisfied with my fitness. I can do a 10k in about 41 minutes when i have been running regularly and i can play 2 hours + without feeling sluggish generally.
My gym work outs are becoming more frequent though i dont really like to do indoor gym work that much , i prefer to do stuff outdoors.
I do hills every once in a while and feel that does great in a short time for the explosivitiy and metabolism.
I do downhill skiing in the winter but dont feel it does a whole lot for my tennis.
Want to do some more swimming and or some yoga but GF and kid limit my time .