I haven't been here in awhile, but I found no posts on the Masai tribe... well some of them could be high jumpers.
Note that they do not use much arm swing. In fact, any arm swing they do use goes in the opposite direction of what we think of as an arm swing; they swing thair arms slightly back and up, shrugging the shoulders a bit. Some get pretty high!
http://www.youtube.com/watch?v=WJElkJNZnY4Guy at 00:27 looks pretty nimble - more so than any one else in the other vids on youtube. I'm sure there are many more specimens like him
Compare with Ced Norman, masai descendant (just kidding), i'm sure many have seen this video
http://www.youtube.com/watch?v=HcCSKHgLykQWith proper arm swing that guy at 00:27 maybe jump just as high as Ced?
Also, notice some of them bend their knees inward a bit to jump higher