As we get older, our bodies start changing.  We’re not able to do all the things we could do when we were in our twenties.  When we’re in our thirties, human growth hormones start declining to a considerable degree and diminish throughout the rest of our lives, so that by the time we’re in our forties and fifties, these hormones are greatly reduced.  That’s just one of the reasons we should develop healthy habits while we’re young to help get us through the years to come.