A long-term Swedish study spanning 47 years tracked the development of physical fitness and strength in adults over nearly five decades. Research has revealed that fitness and strength begin to decline around age 35, with this decline getting progressively worse with age. A positive finding of the study is that adults who decided to start exercising even at a later age achieved an improvement in their physical capacity of up to 10 percent. This finding indicates that physical activity has a positive effect on fitness, regardless of the age at which a person starts exercising. The results highlight the importance of maintaining physical activity throughout life, as regular exercise can slow physical decline and improve physical capacity even in the elderly.