When the weather is cold, the testicular contraction actually moves up and down, and it feels awkward. How come...

This is a very normal phenomenon, because the testis needs a relatively stable low temperature environment (so as to maintain the normal vitality of sperm), and this function is completed through the scrotum.

When the ambient temperature is high, the scrotum expands, which increases the contact area with the ambient air, but heat dissipation and testicular reduction are more conducive to cooling.

When the ambient temperature decreases, the testicular temperature decreases. For example, when the ambient temperature is lower than normal, the scrotum contracts and hugs, and the testicles are raised, as close as possible to a small part of the lower abdomen to maintain the normal temperature and avoid catching cold. The scrotum, which regulates the temperature, moves the testis up and down, so this is a normal protective effect on the testis.