Our bodies can lie to us. For example, when you first start serious strength training, almost any program will produce dramatic results. It is possible to gain 10-20 pounds of pure muscle during your first year of training, depending on your genetics.
These rapid gains might lead you to believe that the program you followed was optimal, but newbie gains are always the easiest and most rapid gains we will ever make. We can make good progress on even a mediocre program. What you make progress on after your first year is a much better indication of what is effective for you.
We can develop a hard-lean physique in our teens and early twenties focusing exclusively on cardio based activities like running. This might lead us to believe that we don’t need strength training, but this is another trick of the body. The physique will not last if we don’t begin to include strength training into our routine. As we age our hormone profile changes; after the age of 28, our body begins to lose muscle mass if we don’t engage in strength training. The condition, Sarcopenia, results in approximately 3 to 5% loss in muscle mass each decade. The average male can lose about 30% of their muscle mass during their lifetime.
Cardio training might produce a pump in our muscles, but it doesn’t sufficiently tax our muscles, if it did, we wouldn’t be able to sustain it very long. Much of the weight gain we experience as we age is due to sarcopenia. Muscle is active tissue. When you allow your muscle mass to decrease, you will reduce your metabolism. You will burn fewer calories all day long, whether you are sitting on the couch or running through the park. If you allow the condition to go unchecked, you will end up with a skinny fat body.