Professor Jung Se-hee of the Department of Rehabilitation Medicine at Seoul Boramae Hospital runs on the track in Boramae Park, Seoul, Oct. 30. Just three days before this photo, she completed the Chuncheon Marathon at 3:42:11. Korea Times photo by Ha Sang-yoon

Jung Se-hee, 47, a rehabilitation medicine professor at Seoul National University College of Medicine and Seoul Boramae Hospital, has been a committed runner since 2003. She logs 10 kilometers along the river every morning, has completed over 30 full marathons and achieves semi-professional marathon times in the three-hour range.

Jung welcomes the recent running boom, especially among those in their 20s and 30s recognizing the physical and mental benefits of the sport.

However, she notes that misconceptions are spreading along with the trend, confusing beginners with debates about the "perfect" form and technique. Olympic marathon gold medalist Hwang Young-jo even joined YouTube recently to fuel the disputes.

To clarify, Jung, both a physician and seasoned runner, says, "I hope people don't waste time and money on misguided advice. Rather than worrying about foot placement, it's more beneficial to run as often as possible."

Here, Jung offers insights on how to enjoy running healthily and happily for the long term.

Q: What's the appeal of running?

A: Running benefits both body and mind, bringing vitality and reducing daily stress. Thoughts come and go as I run. I recommend outdoor running; it clears the mind, relieves stress and offers fresh scenery. Writers like Haruki Murakami love running for similar reasons, I believe.

Professor Jung Se-hee runs in the 2022 Boston Marathon / Courtesy of Jung Se-hee

Q: You've mentioned in blogs and books that running is good for brain health.

A: It's well-documented in research. For instance, running slows the degeneration of brain cells in conditions like Parkinson's disease, which medication alone can't fully prevent. Medications act symptomatically, like wearing glasses — they don't improve eyesight itself, just adjust it. Yet aerobic exercise can delay the progression of such diseases.

Q: So, it doesn't have to be running?

A: True, but running is simple to start — just put on shoes and go. Humans have been running for millions of years, and that's part of the appeal — anyone can do it without special training.

Q: Is strength training a substitute for aerobic exercise?

A: No. The key indicator of health is cardiorespiratory fitness, which only aerobic exercise can build. Strength training can shape your body, but if you aim for health over appearance, aerobic exercise is essential.

Q: What about concerns that running damages the knees?

A: Not true. Yes, running puts force on the knees, but with adequate strength, they can handle it. Running actually benefits joints by strengthening thigh and glute muscles, which protect the knees. Studies show that people who run regularly have lower rates of degenerative arthritis than non-runners. Knee-harmful activities are high-impact sports with rapid direction changes, like tennis or soccer.

Professor Jung Se-hee speaks during an interview in her hospital lab on Oct. 30. Korea Times photo by Ha Sang-yoon

Q: Is walking 10,000 steps a day enough exercise?

A: No, for the average person, walking isn't enough to build cardiorespiratory fitness. To boost this, you need exercise that makes you breathe harder, increases heart rate and makes you sweat. Walking mainly burns calories and gets you moving. Walking counts as exercise only for older adults over 80.

Q: Does excess exercise become harmful?

A: No. Studies show that even with high-intensity exercise exceeding recommendations, mortality and disease rates remain lower than in inactive individuals.

Q: I'd like to take a running class for form correction.

A: I don't recommend classes focused on "perfect form." Exercise has no definitive "correct" form; everyone's ideal form varies with their strength, experience and body type. Worrying about technique can reduce efficiency and raise injury risk. Run comfortably without overthinking arm movement or foot strike.

Q: Any form corrections to avoid?

A: Avoid over-striding or creating too much vertical motion, as these can strain the knees and waste energy.

Q: Are carbon shoes necessary for running?

A: Not for beginners. They're like getting a luxury car right after passing a driving test. Carbon shoes enhance ground response and reduce fatigue, but without proper strength and technique, they could increase injury risk. Basic running shoes are enough for beginners.

Professor Jung Se-hee runs in the Chuncheon Marathon, Oct. 27. Courtesy of Jung Se-hee

Q: I'm planning to improve my diet alongside exercise. Any recommendations?

A: Health can't be solved by food alone. Lifestyle and exercise are far more important. Moderation, avoiding processed foods and limiting sugars matter, but the idea that certain foods like tomatoes or blueberries alone boost health is misleading.

Q: Running solo vs. in a group — what do you recommend?

A: I run alone but find that group runs make the experience easier and more enjoyable, as they shift focus away from physical strain. I support any trend that encourages more people to run and create a positive influence on others.

'Start running — your body will remember'

Jung advises that expecting health without vigorous exercise is unrealistic. She often demonstrates proper form to patients in her office, underscoring the importance of exercise.

"Even if you exercised decades ago, your body remembers it, and this affects recovery," she says. "That's why ‘exercise savings' before illness are so essential."

This article from the Hankook Ilbo, a sister publication of The Korea Times, is translated by a generative AI and edited by The Korea Times.