If we start with visual comparisons, fat tissue occupies more area than the muscle tissue. We can also explain it as fat tissues are less dense that muscle tissue. So, what does it mean? It means that 1 gram of fat will have more volume than 1 gram of muscle as we have already mentioned that muscle tissues are very dense in comparison to fat tissue. We can also take it as a person with 80 kg of weight and 30% of fat will appear leaner than the person with same weight (80 kg) and 40% of fat.
What is body fat or Adipose tissue?
In scientific terms fat tissues are known as Adipose tissue. It is defined as loose connective tissue composed mostly of adipocytes. Adipocytes is basically a cell specialized for the storage of fat. In humans, adipose tissue is located beneath the skin, around internal organs, in bone marrow, intermuscular and in the breast.
Now the next question comes in is what is obesity? So basically, obesity is a condition of a body where excessive adipose tissue (body fat) gets collected near abdomen and other areas of body making it very bulky.
What is muscle tissue?
Muscle cells are made of protein filaments of actin and myosin. These protein filaments are responsible for change in the length and shape of the cell. Muscles helps body to change and maintain a posture, movement and many other functions inside body. Muscles functions to help body to produce force and motion. There are three types of muscles.
First one is skeletal muscles, which is responsible for movement and maintaining posture, a normal human being can fully control this muscle.
Second type is cardiac muscle, we cannot control this muscle and this muscle is found only in heart.
Third type is smooth muscle, this is found under the walls of organ and structures. These muscles are not under our conscious control.
Some more points
If we say we can convert fat into muscle then we are wrong because we cannot convert fat into muscle but what we can do is we can lose fat and gain muscles. Exercise is the best way to lose fat and gain muscles.
Another point on why muscle tissues are better than fat tissue is that the muscle tissues require more calories in comparison to fat tissue which means your body will burn more calories if it has more muscle. Let me give you an example, suppose there are two persons, person A and person B having same weight but person A has more muscle in comparison to person B and if they eat same amount of food the chances of gaining weight for person A is very less than person B because person A body will burn more calories to maintain the body functions than person A body.
So even if you are doing exercise and your body dimensions are changing then also there is very high chances that the body weight will change very less or will not change at all because at one hand you are losing fat which is causing the change in body dimensions making it look lean and on another hand you are gaining muscles which is far denser than fat and hence not increasing the body dimensions but allowing the weight to change very little.
By now you would have understood what is body fat and what is muscle tissue and there is nothing common between these two. We can increase the physical work we do every day to reduce the amount of fat percentage in our body and make our body look lean and fit but this does not guarantee weight loss.