The rate of fat and skinny people gaining muscle differs.
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There is a widespread belief in the world of fitness that fatter people are physically able to gain muscle quicker and easier than their skinnier counterparts. However, this is not a rule set in stone. Muscle gain in individuals can depend on different factors since everybody's physiological chemistry is different.
A normal man of average weight and height can gain muscle mass of 0.25 to 0.5 pounds a week. An average woman can gain between 0.12 to 0.25 pounds per week. This is only achievable with a near-perfect workout schedule that includes strength training, diet, recovery and consistency. In addition to the workout routine a person may use as part of his muscle-building strategy, his rate of muscle gain will greatly depend on other factors.
Hormones That Help and Hinder
The common perception is that overweight individuals are able to turn their fat into muscle. While this is not exactly the case, there are hormonal processes that work to make it appear so. When a person has excess body fat, they can develop a condition called systemic insulin resistance. Insulin is a hormone required by cells to take in glucose for energy. This condition is correlated to excess body weight because cells can become insulin-resistant from a high-fat diet. The fat cells reject caloric storage because they have reached their caloric capacity. Instead of being stored in the fat cells, glucose, triglycerides and cholesterol are released into the bloodstream. Insulin also aids in muscle-building. Weight training exercises can improve insulin sensitivity, which occurs when the body cells require less insulin to lower blood glucose levels and their uptake of nutrients increases.
When a fat person weight-trains, they appear to gain muscle mass easily, giving the appearance of them turning muscle into fat. This effect is caused by the fact that their insulin-resistant cells are rejecting caloric energy, but their weight training is causing the muscle cells to increase their uptake of nutrients. Therefore, the energy from the fat cells are being used up by the muscles instead. This is a calorie-shunting effect, as your body is taking calories out of cells to build muscle. For skinnier people with lower amounts of body fat, this is different. They will not have enough excess energy from fat to be sent to the muscle cells. Fat cells have less stores of calories to release. Since skinnier people have less fat to begin with, they will not have the energy to shunt to the muscle cells. While they can still gain muscle, results will not be seen as rapidly as they could be observed in a fatter person.
Your ability to gain muscle can be predisposed by your body build. Dr. W.H. Sheldon coined the term somatotypes to describe the different types of bodies according to body type, size and composition. There are three categories of body types: ectomorph, endomorph and mesomorph. Endomorphs are people with a larger amount of body mass. They are generally larger built and can gain weight easily. For endomorphs, strength training can bring about great muscle gain, but that gain can quickly be lost if training halts. Mesomorphs have a broader shoulders and narrow hips. They are able to sustain low body fat and easily build lean muscle. Ectomorphs are what we think of as skinny people. They are slender in frame and have little body fat or muscle mass. According to Dr. Sheldon, ectomorphs are great for aerobic activity, but their lack of musculature makes it difficult for them to build bulky muscle mass. According to Sheldon's somatotypes, larger people gain muscle easier than skinnier people do.
We Are All Different
Fat or skinny, everyone's body is different. Some may be blessed with the genetics and the physiological chemistry to be able to achieve their dream physique, while others may have to struggle for it. These factors should be looked at as a reference instead of a guideline to muscle-building, as they are just biological predispositions that may not apply to everyone. Understanding your body is the best way to build muscle, as you will know what works best for your individual body.