Bodybuilding and race

Has anyone noticed the differences in muscle bellies betweeen the races? It seems blacks tend to have muscle bellies that are further towards the insertion of the muscle compared to whites. This is an obvious advantage in bodybuilding competition, but does muscle belly location correspond to increased muscular performance in any way? I have noticed that open-chained and closed chained exercises seem to place the load on different ends of the muscle when I am performing them. Open-chained exercise such as bench or legpress seem to cause more stimulation near my insertions or on my outer chest and lower vastus muscles. The opposite is true for pushups and squats which seem to place most of the stress over my orgins or inner chest and upper rectus femoris. I have heard the arguments against muscle shaping but can the ratio of open and closed chained exercises in ones routine effect the location of the muscle bellies?

whats a muscle belly? sorry maybe its a stupid question.

Take your biceps for instance. The part where the cross-sectional diameter is the largest or the “peak” is the belly. If your bis and tris have belly’s more toward the forearm the more pleasing your arms will look. You will also have a more distinct transition from shoulder to upper arm.