A study showed that 6 months of exercise can bring a 50-year-old back to the level of fitness he had at 20.
After 6 months of walking, jogging, and cycling, which started slowly and gradually increased to 4.5 hours a week, the subjects in the study had the same aerobic capacity as they had 30 years earlier.
So, in 6 months they reversed 30 years of sedentary lifestyle.
That same study 30 years earlier included a 3-week bed rest. The bed rest was more detrimental to cardiovascular fitness than 30 years of aging.
In other words, move it or lose it. And if you lost it, you can get it back.
Personal Trainer, Fitness Instructor since 1998.