I had a dream once about someone cutting vertical pipes just for giggles, and he would always press against the pipe with a gloved hand (gloved for safety reasons), or have a friend do it (also gloved). Dream person told me the force on the pole was to keep the metal pole from biting down on the blade causing binding.

They said they also prefer a circular saw, but aluminum is pretty soft so you could even cut it with a hand saw if being quiet is more important to you than being quick.