When discussing resistance exercise (i.e., lifting weights), you routinely hear the term "proper or strict form." Most who exercise are familiar with the term, yet few truly apply the principle to their fitness routine. How can it be that we consistently leave out such a critical element? Simply put: it goes against our basic design.
When you perform a physical task - let's say, pick up a box - your body recruits every available muscle for the job. This "division of labor" keeps one particular area of the body from being overworked. Resistance training is the EXACT opposite! Each exercise is designed to fatigue one area of the body and practicing proper form (in theory) keeps other muscles from helping. In essence: we are naturally inclined to cheat or exhibit poor form when we lift weights.
The key to overcoming this dilemma is through movement analysis. I'll use the bicep curl as an example: When I do a bicep curl, the only part of my body that should move is my forearm. Once my elbow moves either forwards or backwards, the angle of resistance is changed and my bicep gets relief. This is why you see people arching their back or throwing their elbows forward while performing this exercise. Their body is simply looking for the most efficient way to complete the movement. Keeping those elbows along the sides of the body and not swaying the torso effectively removes any assitance leverage might provide.
Proper form dramatically affects the amount of weight you can lift. You must understand, however, that you lifted more because you used other muscles (or leverage) to complete the movement. Although you are moving fewer pounds, you are actually making greater use of your energy by focusing on an specific area.
Through concentration and adjusted resistance, one can go against our basic design and focus on a particular area while resistance training. The benefit is more effective use of your energy towards reaching your fitness goals.
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