muscle gain must have amino acids . When muscle fibers are torn by a lot of exercise, the body begins to repair these torn muscle fibers. It will use amino acids to re-synthesize human muscle proteins to repair it. This is a complete muscle gaining process, so the body's adequate protein supply is inevitable, otherwise it will be fatigued!
Regarding nitrogen balance, if you have some knowledge about fitness, you may have heard about nitrogen balance. We introduced the knowledge of amino acids above, which is helpful to understand nitrogen balance. When the quality and amount of protein in the daily diet are appropriate, the amount of nitrogen ingested is equal to the amount of nitrogen excreted from the feces, urine and skin, which is called the total balance of nitrogen. In fact, it is the balance between continuous synthesis and decomposition of protein and amino acids. (Note: Amino acids and proteins are organic compounds containing nitrogen)
In muscle training, nitrogen balance can promote muscle growth. When the intake of nitrogen exceeds the discharge of nitrogen, it is what we often call a positive nitrogen balance (state), and vice versa is a negative nitrogen balance (state). In the case of positive nitrogen balance, the body undergoes anabolism, and muscle recovery and growth occurs; in the case of negative nitrogen balance, the body undergoes catabolism, and muscle decomposition and loss occur; we know that protein will not be stored by the body as energy, so Positive nitrogen balance will not exist for a long time, and timely supplementation is needed to maintain this state. This is the point of supplementing protein after training!