It is never too young to start exercising but most of us, unless actively involved in sport, don’t really bother until we see or feel the signs that our bodies are deteriorating. 
And our bodies are deteriorating at an accelerated rate at each passing year. Research shows that men and women lose more than five pounds of muscle every decade of life due to disuse (Evans and Rosenberg 1992). So, if you gain an average of 10 pounds a decade while losing 5 pounds in muscle mass, you are gaining 15 pounds of fat every decade.
All that fat has great negative impacts on your heart health, your metabolism, your endurance, and your ability to turn it around.
So it is simply not good enough to think that a weekend round of golf, an hour of tennis, or a brisk walk to the office each morning will keep a trim body. Everyone needs to retain muscle mass through strength training. No matter how you feel about resistance bands, dumbbells, or weight machines, building muscle provides overall tone, increased metabolism, maintained or improved bone density, more energy, and overall better health.
How do some people seem to stay young and fit while others seemingly age faster than their years?
