The hallmarks of protein and amino acid restriction in aging and longevity

But does such longevity equate to an strong, energetic life? Considering how protein intake relates to muscle and bone mass, wouldn't one rather live a little less, yet strong and kicking, rather than longer, yet thin and frail?

Important:"...those who are exercising may have higher protein needs or at least be able to consume higher levels of protein or specific amino acids without metabolic risk."