Dads have a big influence on the future happiness and accomplishments of their children. We usually think that comes from their being involved in day-to-day parenting with joy, interest, and interaction.

But it turns out that there are also powerful biological influences that are passed from father to child at conception, and play out for the rest of the child's life.

A study in the journal Cell Metabolism shows that future dads who exercise regularly pass along microRNA in their sperm that gives their children intrinsic exercise adaptability, greater strength, and metabolic health.

The bottom line: A physically fit dad transmits endurance and athleticism genetically, not just by example.

And Dad's hidden influences don't stop there.

Another study, presented at the European Respiratory Society Congress, finds that if a dad smoked at age 15 or younger, his children age faster as they grow up, putting them at risk for premature health problems.

That's because the smoking causes epigenetic changes to sperm that permanently damage its quality.

Listen up, guys: Your health today matters not just for your happiness. Your children's future is affected by the lifestyle choices you make now.

To improve your exercise habits, nutrition, stress management, sleep routine, and more, dive into the great information on the newest ways to maximize your health in my book, "The Great Age Reboot."

And make sure (both partners) to take a daily prenatal multivitamin for at least six months before conception.