I remember the old days when I took photos of sports with a camera where the frame rate was dependent on how fast I could flick my thumb to wind one frame on my Canon EF camera.
AF tracking dependent upon how quickly my brain could react and give instructions to my other hand, which was turning the focusing ring on the lens.
Increasing the focal length, what today often is called "zooming in", was dependent upon how fast I could grab the FD 300 mm f/5.6 S.C. in the bag, turn the classic breech-lock ring on the mounted FD 135 mm f/2.5 S.C., get it off the camera, put the 300 mm on and turn that breech-lock ring to get it to stay there.
Then I upgraded to the FDn 70-210 mm f/4, and boy, I could adjust focus and focal length at the same time! Unless I got too confused, that was a marvel.
Not to talk about when I used that same 70-210 mm lens, but got myself the Canon T90 camera behind it. Suddenly I was capable of wasting film at a rate of 4.5 frames/s, or even a tad more if using a trick. Focusing was still manual, of course.
I still got some good sports photos, or so I found out when the film was developed, but they were definitely fewer and longer apart than what I can accomplish with the 1DX combined with he amazing the EF 70-200 mm f/2.8L IS II USM lens.
With this I'm looking back at my own experience while trying to state that you can do sports with anything, but the success rate will usually be different.
Besides, I find it funnier to take crappy photos with the 1DX than with the 400D I also have, somewhere.