later years,or the beginning of the aging process ,occur at different times in different people. people who have exercised regularly and eaten a balanced diet all of their lives may stay active into their late 70s or early 80s. the later years of a person's life are usually marked by a decline in muscle strength. people may move more slowly than before or may need help moving. sense organs such as the eyes and ears may not work as well. the bones of older adults may become brittle and can break more easily. despite these developmental changes, people are living longer today than ever before. this is probably due to a greater awareness of exercise and nutrition, and also to advances in medicine.