Why tummy time for babies? AAP says it can help babies train their neck and upper body muscles to prepare for sitting, crawling and standing. Tummy time advice Babies need to lie on their stomachs the first day home for 10 to 15 times per day, several minutes each time, which can gradually increase. Babies do not like tummy time after trying some many methods? Try tummy time mat! Feedbacks from moms: Babies dislike tummy time and always cry. Nothing worked, until this mat made them fall in love with the tummy time. Tummy time increased from 5 minutes to 20 minutes.