During the shift from one season to the next, many changes also take place in your biological rhythm and, especially as the daily temperature gap widens, your physical immunity can decline and it becomes easier to catch a cold. At such times, maintaining a balanced diet and regularly practicing ki exercises (meridian exercises) that enhance your ki energy circulation will improve the immune functions of your body so that you can prevent colds or, even if you do catch one, get over it more quickly.
When the energy in your body circulates smoothly, your physical body can sustain a healthy condition without any serious problems. However, if the body’s rhythm is suddenly broken from, for example, too much work, malnutrition, sudden drops in body temperature, or severe stress, the system that monitors this jumps into action. This may result in symptoms that indicate a cold.
From the perspective of Western medicine, a cold is an illness that occurs through the invasion of a virus; Eastern medicine, however, sees it as cold energy from outside that has seeped into the body. Accordingly, the prescription for this condition involves removing this cold energy.
The place where cold energy first invades the body are energy points called poongmoon, located about an inch to the left and right sides below the second lumbar vertebra. When cold energy enters through the poongmoon points, the initial symptoms of a cold surface, your nose becomes runny, and you feel cold. It is important to keep the areas of your back and neck, which are more susceptible to this cold energy, warm at all times. Press them with your fingertips or rub them warmly with your palms so that the energy can circulate well.
Here are some exercises that help release cold energy

Standing on your toes
This exercise burns the fat in your lower body, promotes blood circulation, and improves the metabolism to enhance the body’s resistance to illness.
1. Place your hands on your sides and stand up straight with your feet together.
2. As you breathe in slowly, bend your knees more than 90 degrees and tighten your toes and the balls of your feet to sustain your body weight.
3. Hold your breath with the posture, straighten your lower back and spine, and keep your body there for a moment.
4. As you breathe out, slowly stand up. Repeat 5 times.
Shaking your hands and feet in a lying posture
1. Lie on your back. While keeping them relaxed, lift your head, arms, and legs and shake your arms and legs for 1 minute.
2. Shake them for 1 minute, then rest for a moment before shaking them again. Repeat this about 5 times. Lifting your head is effective for releasing cold energy from your spine.
3. Slowly lower your arms and legs and breathe comfortably as you imagine the cold and damp energy from your body coming out through your fingertips and tips of your toes.
— Chungsuk Lee