Overload – How to Force Muscles to Grow

A muscle must be subjected to a stimulus that compels it to adapt and grow. If there is no reason for a muscle to grow, no hypertrophy will occur. Muscles increase their strength and size when they are forced to contract at levels close to their maximum. Much more weight can be lifted with compound exercises than isolation movements. More weight, more overload and in turn more muscle. A compound exercise is a movement that involves more than one major muscle group. It involves a primary muscle and one or more secondary muscles. An example of a compound exercise would be the barbell squat. The primary muscles are the quadriceps and the secondary muscles are the gluteus and hamstring muscles.

An isolation exercise targets just one muscle. Isolating a muscle during resistance training limits overload and muscle fiber stimulation, therefore it limits growth.

Dumbbell flyes are an isolation movement for the chest, removing the shoulders and triceps out of the movement. A common reason people do flyes is to shape the muscle. This is impossible to do- you cannot change the predetermined, genetic shape of your muscles. You can, however, make them bigger which may appear to change the shape. Isolation movements require less weight and limit overload. They have their place in any training regimen, but not to increase muscle size.

Overload is the primary objective when muscle hypertrophy is the goal. Going through the motions will not produce results, you have to push your body to new limits in order to see increased development. Since heavy weight is the most influential stimulus for muscle growth, you must continue to strive for greater overload. Light weight doesn’t do it, nor does moderate weight.

Maximum overload is the only method that will force a muscle to grow. The degree of this overload ultimately determines the degree of muscle growth.

Muscle “burn” does not stimulate growth, overload stimulates growth. The burning sensation that training brings on is believed by most to be a sign of a successful growth promoting workout. Many seek it out and strive to achieve this burning sensation as an indicator to building muscle. That muscle “burn” is not an indicator of an optimum workout. This burn is caused by infusion of lactic acid, a byproduct of glycogen metabolism in muscle tissue. Things like “feel the burn” are not really what building muscle is about. The burn is a good indicator of performing an exercise correctly and targeting the muscle properly. You can get a good “burn” by doing 20 repetitions. However, training at that rep range does not efficiently overload the muscle.

The muscle “pump” you experience when training is a result of blood actually being “trapped” in the muscles being trained. It is certainly a good psychological boost during training and accompanies just about all resistance exercise. The pump will become greater as your muscles grow larger. Now while this muscle pump is not really a bad thing, it is not necessarily an indicator of optimum muscle overload. Many people seek out the muscle “pump” by doing high repetition exercises. Numerous studies have shown that high-resistance, low-repetition exercises are more effective than low resistance, high-repetition exercises in promoting muscle hypertrophy.

The last point to consider is that muscles appear to have a memory effect that is significantly influenced by the last set that you did. If you finish each exercise with a heavy set, your muscles remember this and adapt accordingly. Many people decrease the weight on their last set and “rep out”. This is detrimental to what you are trying to accomplish and will impede muscle growth. The muscle memory effect is an important physiological phenomenon and should be used to your advantage in gaining muscle size and strength.