The lumen of the trachea is lined by pseudostratified columnar epithelium. Note that all the surface cells have cilia at their free (apical) surface. (What function do these cilia serve in the trachea?) Mucus-secreting unicellular gland cells (goblet cells) are interspersed among the ciliated cells.
Donât think you need to be able to do the modified version perfectly before you try theseâyou just need to feel brave enough to go upside down. To complete a handstand push up: 1  Face a wall in a standing position.  Kick your feet up so youâre in a handstand position against a wall.
If it bothers you to do a set of push-ups to the point where you canât perform them correctly, then no biggie. Start off by placing your hands on a bench, chair, or even on the wall (walk feet about 3-fee away). By having your body at an angle, you will be placing less weight (and pressure) on the wrist.