FIG. 6.

Bioenergetic failure occurs when mitochondrial function declines below a functional threshold. (A) If mitochochondrial durability and functional decline rates are equivalent, the time required to fall below the disease threshold is determined by the baseline level of mitochondrial function. (B) Given equivalent baseline levels of mitochondrial function, more durable mitochondria with slower rates of age-related decline will remain above the disease threshold longer than less durable mitochondria with accelerated rates of age-related decline.