Across the board, fitness and exercise should be regularly implemented by every able-bodied person in the world regardless of age, race, gender, religion, etc. As a human being with skeletal system, a muscular system, a central nervous system (and more) it is essential to stay active through different means of activity be it swimming, jogging, rock climbing, biking, lifting or even simply just walking. However, there are a few things to take into consideration when it comes to working out for different age groups.
For a young lifter, particularly a beginner just starting out, calisthenics will yield the best results without the risk of injury or growth stunting. Going overly heavy would result in either injuries or slightly stunted growth. As a teenage lifter approaches 18 years old, they can begin to challenge themselves and start to lift a bit heavier. This can continue until a surprisingly older age. People above the age of 65 (retired people, seniors, etc.) have been increasingly competing in physique competitions to prove their ability to stay in exceptional shape despite their age. Therefore, once a person reaches the age of 18, they can basically lift as intensely as they want to and can continue to work in their own abilities unless age deters them from doing so.
Check out an in-depth guide from USN! [HERE]
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