Warming up improperly will impede your ability to maximize muscle growth.  Some people do not warm-up properly and risk injuries as a consequence.  Like the sang goes, “an ounce of prevention is worth a pound of cure.”  Others warm-up at the expense of strength and overload. The goal is to introduce blood into the muscle group and progressively acclimate the muscle and soft tissue for the heavier weights.  The warm-up process should not fatigue the muscle.  You want to save your energy for the muscle building sets.

In essence there are three types of sets- warm-up sets, acclimation sets, and muscle building sets.  No other set should exist if you want to build muscle using maximum efficiency.  Each set you perform should be clearly defined.  You do not want to do what is called pyramid training, an out dated training strategy.  This is where you gradually add small increments of weight with each set while decreasing the reps.  You go to failure each set until you get to your heaviest set.  By doing this you will weaken your muscle considerably before getting to the heavier weights and you won’t be able to maximize the overload.  Overload on the muscle is needed to stimulate muscle growth.  All other sets besides these are merely preludes to the muscle-building sets.

The first thing you should do before starting with the weights each day is perform a 5-10 minute light warm-up on a cardio machine.  You don’t want to burn yourself out here, just enough of an intensity to get the blood flowing throughout your body and raise your body’s temperature.  This is an important step; it prepares your body for muscle overload.  After this, the body becomes less stiff and functions at the optimal level.

Now you can begin with the weights and do warm-up sets.  A muscle not equipped for heavy weight is an injury prone muscle.  Don’t count warm-up sets as part of the number of sets you are doing per exercise for that body part.  The key is to increase blood flow and get the feel of the movement and the weight.  A warm-up set pumps blood into the muscle and surrounding and supporting soft tissue.  This enhances flexibility and elasticity of the muscle.

You want to warm-up the muscle being trained so it can handle maximum overload without risking injury, while at the same time not fatiguing the muscle in the process.  Use a weight that feels light and you can easily do 15 reps with.  Let’s say your 1RM is 405 pounds.  Your warm-up set should be about 135 pounds, 33% of your 1RM.  These should be good smooth reps at a moderate tempo.  After this first set you should rest about 1-2 minutes.  After the warm-up set move on to the weight acclimation set(s).  This is called an acclimation set because you acclimatize your muscle to the weight.

Weight acclimation sets are very important in preventing injury.  You shouldn’t just jump right up to your muscle-building sets without allowing your body to adjust to the heavy overload. However, you do not want to fatigue yourself on these sets either.  A fatigued muscle is a weak muscle.  The goal is to perform each exercise with maximum efficiency; you do not want to expend precious energy.  If you fatigue your muscle prematurely, it will result in poor or inadequate muscle fiber stimulation and overload.

Neither warm-up sets nor weight acclimation sets build muscle, but they are integral to building muscle by conditioning the muscle and supporting soft tissue for the heavy weight.  Weight acclimation sets are a form of warm-up sets that are done to allow your muscles, tendons, joints, and ligaments to become accustom to the increasing weight overload.  They should be done progressively in preparation for the high-intensity; heavy sets (muscle-building sets).  Proper warm-up techniques utilizing weight acclimation sets will enhance your muscle's ability to maximize nerve-muscle contraction and lift heavier weights for maximum overload generation.

Using the 1RM of 405 pounds, your acclimation set could be 225 pounds.  Here you would only perform 5-8 reps, where you probably could get over 15 reps.  This will allow your body to get accustomed to the weight without fatiguing your pectorals.  Rest about another 1-2 minutes after the acclimation set(s) and then move onto the muscle building sets.  All the sets leading up to these heavy sets are merely warm-up sets and are treated as just that and nothing more.  These heavy sets are the only sets that produce muscle growth.  These sets should be done with high-intensity and you should go to failure.

If your acclimation set was 225 pounds, you could now jump to around 315 pounds for your first muscle building set.  Here you could get more reps with 315 than if you had pyramided up in weight.  If you warmed-up and then did 225 to failure, then did 275 to failure and then tried to do 315– you probably would only get 3-4 reps.  However, if you warmed-up and did an acclimation set at 225 and perhaps one at 275 (without going to failure), you would more likely be able to press 315 for 7-8 reps.  Being able to perform 315 for more reps will stimulate more muscle growth.  Save your energy for the heavier overloads and take precaution in the warm-up process.

There is no need for repetitive warm-up sets for the same muscle group within different exercises.  This only adds further fatigue and depletes muscle energy substrates that ultimately rob your muscle's ability to handle maximum overload.  When moving onto the next exercise, start with your muscle-building sets immediately.  For example, if you just finished doing bench presses on a flat bench, there would be no need to go through the entire warm-up process again on incline presses.  There is no need to try and warm-up a muscle again that is already warmed- up.