Limiting Factors

The way you look depends a lot upon your genetic makeup, what you have inherited from your parents. Fitness isn't just a matter of following a certain exercise routine and following a specific diet. You have to consider several other elements, such as your inherent body type and body composition, your lifestyle and the sports you play.
Your body composition is determined by the percentages of lean body mass (the sum of our muscles, organs and bones), fat and water. When you gain weight, you can gain muscle, fat, water or all three. Also when you lose weight, you can lose muscle, fat, water or all three. The factor over here is to determine your body type, as this is very important in determining how much muscle you can gain as well as how much more you ought to fight to lose fat. Now genetics plays a big role in determining the degree to which you can change your body composition. There are 3 very highly simplified body types: ectomorph (long-boned, long-muscled, slender, with little body fat), mesomorph (heavily muscled, stocky build) and endomorph (round, soft, with relatively high body fat). Actually most people do not necessarily fit into only one of these categories, but are a mix of them. But you need not accept your body type as something that cannot be helped as you can alter your body type somewhat by changing your ratio of body fat to muscle and the best way of achieving it is to follow a good and systematic exercise regimen. But in spite of that we all have genetic limiting factors, such as the following:

• Different bone structures. Possibilities include having longer or shorter, thicker or thinner bones.
• Different number of muscle cells. When you increase muscle mass, you increase the size, not the number, of muscle cells. So if you are born with more, you have more to work with.
• Different types of muscle fibre. Some types of muscle fibre (slow-twitch kind) which are good for endurance activities do not get big and thick easily. Other types (fast-twitch kind) get big, thick and strong but are not efficient at endurance activities. And some types are in between. Each of these muscle groups respond differently to exercise and diet and helps determine your body composition. So your appearance will depend on what your exercises or physical activities are.
• Different numbers of fat cells. Your body stores extra calories as adipose tissue in your fat cells. Once you become an adult, their number remains the same, so when you get fatter, you are just stuffing more fat into them. Thus the more fat cells you have, the easier it is for your body to store fat and for you to get rid of them.
• A few other factors as well that we do not yet understand limit your ability to change your body composition. There are different kinds of fat, different kinds of enzymes that control fat storage and retrieval, different distributions of fat around the body, complex bio-chemical combinations of glandular function and hormone output.

Simply put, it means that we can change our body composition to a certain extent, but the end result will yet be determined by your genetic makeup. This need not discourage you. After all, exercise is known to help make changes in your body composition that may surprise you and until you get down to making the effort you will never know your own potential.