[Harumanbo Harucheonja] "Walking releases hormones that eliminate causes of dementia"

Interview with Yang Dong-won, Professor of Neurology at Seoul St. Mary's Hospital
Chairman of the Korean Dementia Association and Director of Mapo-gu Dementia Support Center
Leading Expert in Dementia in Korea

'Irisin' Produced by Exercise Protects the Brain
"Writing is the Most Advanced Cognitive Activity"

"Physical exercise thickens the brain and secretes 'irisin,' which eliminates amyloid beta (Aβ) protein, a cause of dementia. Writing, too, if done actively such as keeping a diary rather than just savoring the content, can help maintain and improve cognitive abilities."

On the 27th, Professor Yang Dong-won, a neurologist at Seoul St. Mary's Hospital, who met with Asia Economy, said that various physical and intellectual activities such as walking and writing can maintain brain health and have a preventive effect against dementia. Professor Yang, who serves as the chairman of the Korean Dementia Association, is one of the leading authorities in the field of dementia in Korea. In addition, as the director of the Mapo-gu Dementia Support Center, he is actively engaged in dementia prevention efforts within the local community.

Regarding the effects of walking exercise, Professor Yang said, "Research shows that the hormone irisin, secreted from muscles during exercise, travels to the brain, enhancing brain function and removing Aβ protein that causes Alzheimer's dementia." He emphasized that "blood flow to the brain increases, brain-derived neurotrophic factor (BDNF), a brain-protective substance, is secreted to prevent brain atrophy, and in some cases, the brain even becomes thicker," highlighting that brain health can be maintained through exercise. He explained, "In the past, it was simply thought that improved blood flow and weight loss naturally reduced age-related diseases, but now it has been proven that exercise supplies beneficial substances that protect the brain."

Professor Yang also pointed out that walking gait is directly linked to cognitive function. When brain diseases such as Parkinson's occur, hands tremble, movements slow down, stride shortens, posture becomes stooped, and shuffling steps appear. Beyond these well-known facts, he warned that slower walking speed increases the risk of dementia. He explained, "Even those with normal cognitive function slow down when walking while thinking or talking, but in cases of subjective cognitive decline (SCD) or mild cognitive impairment (MCI), the difference in walking speed between normal walking and walking while thinking becomes more pronounced." He also noted that this symptom worsens in crowded places. Professor Yang said, "With normal cognitive function, one can perceive the speed and direction of oncoming people and avoid them while walking, but with declining cognitive function, hesitation occurs, slowing down the walking speed."

Yang Dong-won, Chairman of the Korean Dementia Association, is discussing the importance of strength training in old age at the Seoul Catholic Medical School laboratory, demonstrating the heel raise method to strengthen the calf muscles. Photo by Younghan Heo younghan@

However, he emphasized that elderly individuals should adjust exercise intensity appropriately, as walking 10,000 steps a day might be excessive. Professor Yang said, "Considering that elderly people may have joint health issues, walking 10,000 steps at once could be too much. It is better to walk leisurely for about 45 minutes, four times a week, taking breaks, and to promote walking in daily life by using subways or buses instead of cars."

Besides walking, Professor Yang recommended simple exercises that can be done at home. He advised holding onto a bookshelf or similar to prevent falls while raising and lowering the heels, and performing chair-assisted squats within a comfortable range considering joint conditions. He repeatedly stressed, "From the late 70s, sarcopenia often occurs, mainly affecting leg muscles. It is important to keep the lower body strong through exercise."

Regarding writing, he advised not to merely copy texts but to engage in 'thoughtful' copying and to take a step further. Professor Yang said, "Often, people write mindlessly when copying, but it is emotionally beneficial to savor the writing by carefully considering the content and recognizing good phrases." After building writing stamina through copying, intellectual activities such as diary writing and writing reviews should follow. He explained, "Writing is the highest-level cognitive activity humans can perform. It involves remembering personal experiences and feelings, thinking logically, and expressing them again in language, thus engaging the entire brain."

Yang Dong-won, Chairman of the Korean Dementia Association, is demonstrating a chair-supported squat while discussing the importance of strength training in old age at the Seoul Catholic University Medical School laboratory. Photo by Younghan Heo younghan@

Professor Yang also mentioned that various activities should be combined for dementia prevention besides exercise and writing. He said, "The European FINGER program research showed that maintaining consistent aerobic and strength exercise, diet management, and cognitive activities significantly prevents cognitive decline compared to not doing so. It should be done comprehensively and consistently, not just one method." He emphasized that communication with like-minded people, walking together, watching TV together, and writing together are important dementia prevention methods beyond walking and writing.

He particularly stressed the need to reduce stress. Professor Yang said, "Normally, cells do not regenerate as we age, but new nerve cells continue to be produced in the hippocampus. However, stress reduces or even stops the production of nerve cells." If stress is not managed, Aβ protein can accumulate, increasing the risk of dementia.