Final answer:
The described symptoms are indicative of 'overtraining syndrome' or 'burnout,' which is a result of an imbalance between training and recovery. If not treated, it can lead to severe conditions including starvation-like symptoms, acidosis with the potential to induce coma, and various long-term health issues.
Step-by-step explanation:
The term for a deterioration in the usual standard of performance, accompanied by chronic fatigue, apathy, anorexia, indigestion, and weight loss, which can increase the potential for overuse injuries and infections is known as overtraining syndrome or burnout. This condition occurs when there is an imbalance between training.
Recovery time, leading to a breakdown in the body's ability to cope with physical stress. Symptoms like weakness, irritability, depression, and inability to face even minor stress without experiencing 'crises and even death' are indicators of this severe stage of overtraining.
And similar conditions can be seen in starvation and extreme nutritional deficiencies, such as acidosis which lead to lethargy and potentially coma if left untreated. Moreover, various conditions like malnutrition or chronic diseases can result in poor growth, epithelial problems such as cracks in the corners of the mouth, and mental deficits suggesting a broad need for a comprehensive medical evaluation to identify the underlying cause.