Do three sets of 10 to 12 reps. Bent-over dumbbell rows target your posterior deltoids and actively engage your back muscles. This compound exercise improves muscle coordination and strength.

In this introductory guide, we outline the form and function of the avian respiratory system ... Before oxygen is absorbed in the lungs, air flows into posterior air sacs, which collect air as it is ...

Counterintuitively, the (posterior) air sacs behind the lungs fill first ... Avian air sacs have evolved to fit within the coelom (body cavity) without obstructing the flight muscles or vital organs.