Final answer:
Physical exercise to increase muscle mass involves both anabolic and catabolic processes, with the former resulting in the synthesis of proteins and the latter in the breakdown of molecules for energy. These processes work in tandem, regulated by hormones, to both provide energy for exercise and to rebuild and increase muscle tissue.
Step-by-step explanation:
Physical exercise to increase muscle mass involves both anabolic and catabolic processes. During physical activity, catabolic reactions break down glucose into simpler compounds that provide energy to muscles for contraction. Conversely, anabolic reactions, also known as biosynthesis reactions, use this energy to synthesize larger molecules such as proteins from smaller ones like amino acids. These proteins are essential for the growth and repair of muscle tissue, thus increasing muscle mass. Examples of exercises that require these processes include weight lifting, which can lead to the breakdown of muscle fibers (catabolic) followed by their repair and growth (anabolic).
Anabolic reactions also combine other small molecules to create larger structural molecules such as fatty acids to form triglycerides, and nucleotides to form nucleic acids, crucial for forming new cells and tissues. The balance and regulation of these processes are maintained by various hormones in the body, with catabolic hormones like cortisol and adrenaline promoting energy production, and anabolic hormones like growth hormone and testosterone facilitating synthesis and growth.