It used to be that age 55 to 60 would be considered old age for a man or for anyone.
But now with the life expectancy increasing and advances in medicine old age is usually considered to be 80 or above for a man.
Some 70 year old men feel pretty young and do not feel as old as they are.
Even though 70 is not really young anymore it's still not that old for a man or even a woman as long as you stay very active.