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The Difference is RESULTS

Because I SAID So…

The Specific Adaptation to Imposed Demands (SAID) principle, also known as the law of specificity, states that our bodies will adapt specifically to the stresses we regularly place on them. With this basic principle of training we know that in order to improve a certain component of physical fitness, we must train specifically for that component. For example, exercises for strength may do little to improve flexibility, and exercises designed to improve the endurance of arm muscles may do little for the legs. The principle applies to muscle groups, movement patterns, and type of contraction. This is the concept behind cross training; doing a variety of modes of exercise. The best illustration of the SAID principle is seeing it in reverse. The law of reversibility is the opposite of the law of specificity. If we are not training regularly, there is no need for our bodies to adapt. You’ve heard the saying “if you do not use it, you lose it.” Observe the atrophy of muscle of someone with a broken arm or leg once the cast has been removed. If not used, we lose the muscle and the resulting functional ability. I’m often amazed at witnessing this as people age. A very good illustration of the SAID principle is to observe older adults that get very little activity and began to lose functional ability in activities of daily living we take for granted. This process is often blamed on the ‘aging process’ but is in reality the SAID principle in reverse. Our bodies will not allow us to have abilities that we do not regularly and progressively perform.

The SAID principle correlates closely with the progressive overload principle. If you want to improve in those activities you need to perform them at a progressively more intense level as your muscles adapt. An example being if you want to be a better runner, you need to run. If you want to be a better biker you need to bike. And if you want to sit and stand and climb up and down stairs easily as you age, you need to perform those activities, and do exercise that mimic those movements. I see people in their 80’s and even 90’s that have the functional ability of a healthy individual 20 years or more their junior. You probably know of someone in their 60’s or even younger who is already losing functional ability in common activities of daily living, like the simple act of sitting and standing up from a chair. Take note of this and do appropriate exercises that will bode well for you later in life.