As BTS embarks on their ambitious ARIRANG World Tour — spanning 80 concerts across 34 cities and lasting nearly a year — questions about how the seven members will endure the intense physical demands have become a major topic of discussion. In an exclusive interview with The New York Times, the group’s former conditioning coach, Kim Jinwoo, offered rare insight into the rigorous fitness regime required to survive such a grueling schedule.

Kim, 42, who worked with BTS through their first four world tours, compared the members to professional athletes. However, he emphasized that K-pop idols face unique challenges. Unlike traditional athletes, they must build exceptional stamina and injury resilience while maintaining the slim, lean, and highly aesthetic physique demanded by the industry.

“It’s a job that puts much more strain on the body than most people realize,” Kim said during an interview at his sleek fitness club in Seoul. He noted that in addition to performing high-energy choreography on stage, the members endure long hours of rehearsals, fittings, media appearances, and travel, often surviving on as little as four hours of sleep.

According to Kim, much of the physical preparation happens in the months leading up to the tour. The focus is on building core strength, cardiovascular endurance, and muscular resilience, particularly in the lower body and back — areas heavily stressed during intricate dance routines. Daily step counts often exceed 10,000, combined with targeted strength training. Kim revealed that BTS members trained consistently even during their military service periods to maintain baseline fitness levels.

The trainer highlighted that injury prevention is paramount. With complex choreography involving sharp movements, jumps, and rapid directional changes, even minor imbalances or fatigue can lead to serious issues. He worked closely with the members on mobility work, recovery protocols, and personalized programs tailored to each individual’s body type and role within the group.

Now in their late 20s and early 30s, the members — particularly Jin, Suga, and RM — face added challenges compared to their early 20s. Kim noted that recovery takes longer with age, making smart training, nutrition, and rest even more critical. Despite this, he expressed confidence in their professionalism and dedication, saying they have always approached training with the same seriousness as their music.

The ARIRANG World Tour marks BTS’s full-group return after nearly four years apart due to mandatory military service. The scale of the tour is unprecedented even by their standards, with multiple legs across Asia, North America, Europe, and South America. The physical toll of back-to-back concerts, jet lag, and constant performance pressure will test their limits like never before.

Kim’s insights shed light on the hidden athleticism behind K-pop’s polished performances. While fans see flawless choreography and boundless energy on stage, the reality involves months of disciplined gym work, careful diet management, and strategic recovery. He stressed that maintaining the “idol body” — lean yet strong, with visible muscle definition but without excessive bulk — adds another layer of complexity to their training.

As the tour progresses, fans will be watching closely for any signs of fatigue or injury. The group has already demonstrated remarkable resilience during their opening shows in Goyang, delivering high-intensity performances despite the long hiatus. However, sustaining that level across dozens of dates will require meticulous planning from both the members and their support team.

BTS’s commitment to excellence has always extended beyond music and choreography into physical preparation. Kim Jinwoo’s reflections serve as a reminder of the immense dedication required to remain at the pinnacle of the global music industry for over a decade. With the ARIRANG World Tour now underway, the coming months will test just how effectively that preparation translates into enduring success on one of the biggest stages in the world.