Does yer micky shrink after exercise

[meath chap]

I just ran 12k and my micky has shrunk to half the size is any one else the same.

yep that happens me only with running or long strenous walks,it just goes into cave man mode... cycling on the other hand makes it numb as fuck,when i get off the bike i get this awful tingling sensation in that department

[Jetstream]

All down to blood supply... blood supply enables erection... exercise increases heart beat in order to pump oxyginated blood through the body... which reduces pooling effect in blood vessels of the penis. As regards numbness due to cycling... your saddle is evidently the wrong type....