"You who are young, be happy while you are young, and let your heart give you joy in the days of your youth. Follow the ways of your heart and whatever your eyes see, but know that for all these things God will bring judgment." NIV translation
We all have done things and chalked it up to our youthful foolishness and this verse speaks to that. We can follow our own ways and have a good time. God sees all things and those days will end soon enough so it is best to accept Jesus and the wisdom of God at an early age.
"So then, banish anxiety from your heart and cast off the troubles of your body, for youth and vigor are meaningless." NIV translation
We can grow old and strong in the Lord or we can try to resist both time and God.
It seems that many people chase after their youth and will spare no expense in trying to cheat time.
In the end that is futile because God has decreed a day to judge all men and an end to this time.