Just to make sure that everybody is on the same page...
The dolicomorph, brachiomorĥ and mesomorph body type classification was drawn up by A.I. Mulchin in 1972.
Accordning to him :
Dolichomorphs: individuals with long upper and lower extremities and a relatively short and wide torso.
Brachiomorphs: individuals with shorther upper and lower extremities and a relatively long, narrow torso.
Mesomorphs: individuals with a proportional extremities-torso ratio.
In these individuals the arm and leg length as well as shoulder width come up to:
arm = 45-46% of height
leg = 54-55% of height
shoulder = 23% of height
arm = 42-43% of height
leg = 50-51% of height
shoulder = 25% of height
arm = 43-44% of height
leg = 52-53% of height
shoulder = 24% of height
Brachiomorphs are structurally built to lift a lot of weight on movements such as the bench press and squat.
Their upper body push workouts should revolve around a small selection of movements, mostly big pressing exercises like the bench press, decline press and push press/military press.
Same thing could be said for their lower body training, they could only perform squats (front and back) and gorw big legs.
On the other hand they will need more exercise variation for the upper body pulling muscles. Various types of pulls should be used.
They will also have problems building-up their deadlift so they should include more posterior chain exercises.
So to recap:
Few pushing movements (but more sets per exercises). Best to train these exercises in the 3-5 and 6-8 rep ranges
Few leg exercises (but more sets per exercises). Also in the 3-5 and 6-8 rep ranges
More pulling exercises variety. Perform exercises in the 6-8, 8-10 and 10-12 rep ranges. You will need to use advanced techniques such as iso-dynamic contrast and tempo contrast.
More posterior chain exercises (read coach Poliquin's article on hamstring for a few good ideas).