gland = special tissue that secretes a hormone or other bodily fluid
glans = head of the penis
In spite of what you hear, or read, it’s difficult to enlarge the glans. The main erectile chambers of the penis, the corpora cavernosa (CC), are surrounded by the tunica albuginea. The tunica is a resistant tissue that is strong enough to contain the blood under pressure that creates an erection. PE exercises for the tunica work because the put greater than normal pressure on the tunica causing it to stretch or have micro-damage. It repairs itself to accommodate the greater pressure and thus becomes larger.
The glans has no tunica. It’s just spongy tissue that easily expands, you can make it bigger with a Kegel squeeze (contraction of the BC muscle), but it also easily returns to its original shape and size. Some have been able to make it larger, but it requires dangerous levels of pressure (search for Uli’s exercise). Vacuum pumping, on the other hand, lowers the pressure surrounding the glans and relies on your internal blood pressure to expand it. The more the outside pressure is reduced, the larger the glans becomes. But it’s never expanded by more than your normal blood pressure unlike the manual exercises (like the Uli) which put greater than normal pressure on it.
The extreme pumpers you see on sites like tigerpumping.com may have lymph fluid buildup that usually doesn’t last long. Pumping for hours isn’t going to help.
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