Because...
The importance of a healthy diet will dramatically show through the individual's physical functions, the performance of an individual relates to the diet they follow, having a poor diet with insufficient amounts of nutrition will lead to underperforming bodily functions, maintain proper benefits from the work one does, it is just as important to receive the building blocks to recover from muscle tears and even in general living.

"Bulking"
This refers to a specific cycle in bodybuilding where a person eats excess amounts of calories to gain more mass, this way of eating allows the body to use the calories to build more muscle boosting a person's weight if that is their goal to do so, but coincidingly increase strength gains. There are many approaches to bulking, typically the amount of calories recommended to intake is between 20-25 kcal per pound of body weight. Another way to bulk is to additionally eat 250 calories more than usual, and once gaining weight stops, add another 250, and perform until the goal has been met.
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"Clean Bulk"
This refers to eating just enough to increase lean body mass while minimizing the gain of fat. To do this, excessive amounts of protein will have to be consumed, and to lower body fat, cardio exercises will have to be performed. Because of the detailed amounts of nutrients needed to perform this diet, it is important to keep track of the nutritional value of what is being consumed. This approach typically takes longer to gain a significant amount of weight in a short time but promotes a leaner body composition.
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"Dirty bulk"
This refers to eating every possible calorie to gain over-excessive amounts of mass in as short and fast a way as possible, here will show the most result in weight progress as the amount of calories is way over the normal expected amount originally taken in. The downside is due to the lack of care for what is being put in the body, many effects of overeating unhealthy foods just for calories come into play. When doing this, an excessive amount of exercise must be performed to balance out the rapid weight gain.
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