Perhaps watch The Great Sperm Race – BBC doco . .
Look also to ROS – Reactive Oxidative Stress
If you did not a few pages ago please download this eBook on ‘Research into Improving Sperm Quality” research into sperm improvement (2017)
It explains how you may have ended up with less than you want (optimal sperm, and general health)
The second half talks you through what you can do about it..