Sex secrets that every man needs to know

　　18 years old, yes male The "peak" age of sexual function, because the secretion of male hormones is strongest at this time. But due to lack of experience, men of this age may not have the best sexual performance.
　　
　　15cm. After 90% of men have an erection, their penis length is about 14-16 cm, with the majority being 15 cm. However, if a man is obese or overweight, his penis will be much shorter.
　　
　　45 kilometers/hour refers to men ejaculation time speed. sperm From the vas deferens to the glans, it rushes forward at a "medium speed". However, once it enters the vagina, it slows down sharply, as if thousands of troops are driving from four lanes onto a one-way lane at the same time. Generally, it takes sperm 5 minutes to crawl to arrive Uterus neck, and then it takes 72 hours to "meet" the egg.
　　
　　5 calories. The volume of a single ejaculate is equivalent to a mouthful of phlegm and contains approximately 5 calories. “This is considered high in calories because semen is rich in fructose and biological enzymes. ”Mark Goldstein, professor of reproductive and urology at Cornell University, said.
　　
　　64 liters. The volume of male ejaculation is about 2-7 ml each time, and 64 liters can be produced in a lifetime, much of which is prostate fluid.
　　
　　10 hours. Swiss research found that most men's body functions have been fully restored about 10 hours after sex. The so-called "you can't have sex before a competition" is a complete fallacy. Of course, as age increases, the recovery time for some men will be appropriately extended, taking about 12 hours.