不要对自己将来的能力过于乐观 否则害人害己

WebMD: Erectile Dysfunction Common With Age

http://www.webmd.com/sexual-conditions/guide/20061101/erectile-dysfunction-common-with-age

 A new study shows that as men age they eventually will come face to face with erectile dysfunction (ED), commonly known as impotence.

The research, published in the August 2003 issue of Annals of Internal Medicine, shows that ED is common among older men and sexual function sharply decreases after age 50.

...

The majority of younger men (74%) rated sexual function as good or very good; only 10% of men older than 80 rated sexual function the same.