As a domain expert in the field of human physiology and biomechanics, I can provide a comprehensive understanding of how growth occurs in the human body, especially in relation to sleep and wakefulness. Step 1: English Answer Growth in humans is a complex process that involves various biological systems and hormones. It is not limited to the period when we are asleep; rather, it is an ongoing process that occurs throughout the day and night. However, certain phases of sleep are particularly crucial for the growth and repair of tissues. Firstly, it's important to clarify that growth is not synonymous with muscle growth. Growth can refer to overall body development, which includes the growth of bones, muscles, and other tissues. Muscle growth, on the other hand, is a specific aspect of growth that is often associated with physical training and exercise. During the day, the body is engaged in various activities that can lead to muscle breakdown. This is a natural part of the process where the body uses energy and exerts force, leading to the micro-tearing of muscle fibers. However, the body is also constantly rebuilding muscle fibers, even in individuals who do not engage in regular physical training. This rebuilding process is a part of the body's natural maintenance and repair mechanisms. Sleep plays a vital role in the recovery and growth process. During sleep, particularly in the deep stages and the REM (Rapid Eye Movement) phase, the body experiences a surge in the production of certain hormones that are critical for growth and repair. One of these hormones is human growth hormone (HGH), which is secreted by the pituitary gland. HGH is known to stimulate cell reproduction, regeneration, and growth, which includes the growth of bones and muscles. Moreover, sleep is also associated with the release of testosterone and insulin-like growth factor 1 (IGF-1), both of which contribute to muscle growth and repair. These hormones are released in higher concentrations during sleep, which is why adequate sleep is often recommended for athletes and individuals looking to improve their physical performance. However, it's also worth noting that the body continues to function and grow during wakefulness. The body's metabolic processes, including the synthesis of proteins and the repair of tissues, do not cease when we are awake. In fact, the energy and nutrients consumed during the day contribute to these processes. In conclusion, while sleep is undeniably important for growth and repair, the body does not cease to grow when awake. It is a continuous process that involves a delicate balance between breakdown and synthesis, occurring both during sleep and wakefulness. The key is to ensure that the body has the right conditions, including proper nutrition, adequate sleep, and regular physical activity, to support healthy growth and development. **read more >>

They don't ONLY grow during sleep. Your body is constantly breaking down and rebuilding muscle, even in people who don't train at all. ... During certain cycles of sleep the body dumps certain androgenic hormones into the bloodstream at significantly higher levels than when you're awake.read more >>