By Mallika Marshall, MDBOSTON - Local researchers have found that men who lift heavy objects may have higher sperm counts. found that among couples seeking treatment for infertility, men who frequently lifted or moved heavy objects at work had 46 percent higher sperm concentration and 44 percent higher total sperm count compared to men with less physical jobs. found that among couples seeking treatment for infertility, men who frequently lifted or moved heavy objects at work had 46 percent higher sperm concentration and 44 percent higher total sperm count compared to men with less physical jobs