Losing Energy the More You Exercise? Overtraining Syndrome and How to Exercise Healthily

The depletion of qi and blood and the weakening of sinews and bones described in Donguibogam closely match the way modern medicine explains overtraining syndrome. It is a complex physical and psychological issue that extends beyond simple muscle soreness. In response to the physical stress of exercise, the body activates the hypothalamic-pituitary-adrenal axis, which triggers a fight-or-flight response. Appropriate exercise strengthens this system, but excessive exercise continuously stimulates the hypothalamic-pituitary-adrenal axis, chronically elevating levels of the stress hormone cortisol or depleting it altogether. Once this hormonal balance is disrupted, athletic performance declines, and psychological difficulties such as poor sleep, low mood, and anxiety can follow. Overtraining also hyperactivates the sympathetic nervous system, lowering heart rate variability and suppressing the parasympathetic nerve function needed for recovery. This reduces the body's capacity to finely regulate the heartbeat and lowers overall physical recovery. At the cellular level, mitochondria dysfunction reduces energy production efficiency, while chronic systemic inflammation slows muscle repair. The immune system also weakens, leading to more frequent minor illnesses like colds. Over the long term, the secretion of anabolic hormones such as growth hormone and testosterone is suppressed, hindering muscle development and tissue repair, while altered thyroid hormone levels can slow overall metabolism. Overtraining syndrome is not merely feeling tired from working hard; it represents widespread strain across the neurological, endocrinological, and immunological systems. Balancing exercise with intentional rest while paying attention to your body's signals is far more productive than simply increasing workout volume.