How Muscles Grow
After you finish an exercise, your muscle needs to repair itself. To do this, satellite cells that surround the muscle fiber fuse, forming a larger, stronger muscle. The more muscles repair themselves, the more visible the muscle growth. To gain muscle as fast as possible, you must cause the right amount of muscle damage, eat the correct nutrients and allow enough time for the muscle to repair itself.
According to the University of New Mexico, growth factors are any hormones or hormone-like compounds that speed up muscle growth. For example, the release of the growth factor "growth hormone" is triggered by the intensity of the exercise you perform. Growth hormone causes more fat to be metabolized for muscle growth and increases the uptake of amino acids, the building blocks of cell repair.
The type and intensity of your exercises affect your rate of muscle growth. Northwestern Health Sciences University (NHSU) recommends high weights and low repetition. Use weights that are heavy enough for just a few repetitions. NHSU suggests four to eight sets of an exercise that you are only able to perform one to four times. Be aware that heavy resistance training is more likely to cause injuries. Also, allow your muscles a day or two to repair themselves between workout sessions.
Your body will quickly recover from an exercise if the nutrients it needs are readily available. To gain half a pound to a pound a week, UCLA recommends adding up to 500 extra calories a day. Because your body needs protein to build muscle, 15 to 20 percent of your total calories should be from healthy protein sources, such as eggs, lean meats, soy products and nonfat dairy. A balanced diet, such as the one the U.S. recommends, supplies all the nutrients you need for rapid muscle growth.
Creatine supplements claim to speed up the muscle growth process. However, UCLA cautions people to learn the facts before using creatine. While there does appear to be evidence for the benefits of creatine, there is no long-term safety data. They advise creatine users to stick to the recommended dosages, drink plenty of water and keep an eye out for detrimental body changes.