Some scriptures about aging (paraphrased)....
God heals us of every disease and our youths are renewed like the eagle (Psalm 103)
God carries us, even unto old age, when our hairs are grey (Isiah 46)
Those planted in the house of the Lord shall still bear fruit even in old age (Psalm 92)
Caleb said to Joshua, when he was already 80 years old - I am as strong now as I was 40. Therefore give me this mountain! Joshua 14.