  Cellular senescence is thought to play a major role in age-related diseases,
which cause nearly 67% of all human deaths worldwide. Recent research in mice
showed that exercising mice had higher levels of telomerase, an enzyme that
helps maintain telomere length, than non-exercising mice. A commonly used model
for biological aging was proposed by Penna. I propose two modifications of the
Penna model that incorporate senescence and find analytical steady state
solutions following Coe, Mao and Cates. I find that models corresponding to
delayed senescence have younger populations that live longer.
