Many people use treadmills for weight loss. Before becoming a Korean medicine doctor, I also struggled—thinking that just exercising hard would make the fat disappear, only to face rebound weight gain. Based on that experience, I now advise patients to check a few things before starting. First, if you feel heavy and bloated in the morning upon waking, suspect Spleen Qi Deficiency. When the spleen’s function is weak, energy production is impaired, so exercise leaves you exhausted without weight loss. In this case, it is better to first strengthen the spleen with herbal medicine and start with walking rather than pushing the treadmill speed. Second, if you become short of breath or dizzy during exercise, this is a sign of Qi and Blood deficiency. Running high-intensity intervals on an empty tank can cause muscle loss and drain your vitality. I found that maintaining a heart rate of 120–130 bpm for over 30 minutes of steady walking was more effective. Third, if after exercise you crave salty foods, meat, or carbohydrates, Stomach Heat may be the cause. Excess heat in the stomach disrupts appetite control, creating a cycle of burning calories only to replenish them. Changing meal order or drinking peppermint or ophiopogon tea to cool the stomach can help. Finally, if none of these apply but weight still does not drop, Phlegm-Fluid retention or Blood Stasis may be building up in the body. Phlegm-Fluid is like waste clinging to blood vessels and tissues, obstructing metabolism, while Blood Stasis blocks circulation and hinders fat burning. In such cases, exercise alone cannot resolve the issue; you need to first clear these internal stagnations with herbal medicine or acupuncture before the treadmill becomes effective. Ultimately, using the treadmill is most beneficial when your body is ready. Since constitution-based approaches differ, visiting a Korean medicine clinic for consultation is a good option. I’m not trying to scare you—I’m sharing this because I’ve made those mistakes myself.