On September 24, 2025, BTS fans went into a frenzy after professional bodybuilder Ma Sun-ho uploaded a new YouTube vlog featuring BTS' Jungkook, RM, and V from their stay in Los Angeles. The video was filmed during the group’s extended trip to LA earlier this year. The members regrouped after completing their military service to prepare for their comeback album, scheduled for spring 2026. The 20-minute vlog, titled LA Vlog Ep.1 (feat. BTS), showed the trio training under Ma Sun-ho’s guidance at a gym. According to the YouTube video's description, Ma Sun-ho said that BTS worked with great passion and dedication. The footage captured several moments of the members lifting weights and sharing lighthearted banter. However, it was Jungkook who quickly stole the spotlight with his intense workout session. In one clip, Jungkook was seen on a bench, lifting dumbbells while partially covering one side of his torso, seemingly to hide his tattoos.His determination stood out as RM and V hyped him from behind to push through the set. As soon as the vlog dropped, ARMYs flooded social media with reactions.Netizens flocked to social media to praise Jungkook’s post-military transformation. An X user, @windbladies, wrote,vani⁷ @windbladiesLINKI just saw the first two seconds of the video and didn’t think it was Jungkook because there were no tattoos! Omg, this is INSANESome fans joked about how surreal it felt compared to earlier years when even a glimpse of the members’ foreheads caused excitement.Emily⁷ ⟭⟬💜 @emily_bts_7LINKREMEMBER WHEN WE THOUGHT A BIT OF FOREHEAD WAS SCANDALOUS!!!NM⁷ @agustdhuhLINK@archivesofkook Now imagine if he would have showed the tattooed armlayla⁷ @my_mikrokosms7LINK@archivesofkook IF HE HAD SHOWN TATTOOED SIDE I WOULD'VE BEEN ASCENDED TO HEAVENLouffyisaSTAR🫧🏳️‍⚧️🇨🇲⁷ @louffyDGLINK@dreamjeons Yall seee how huge his upper rip cage is?? OH HE AIMING FOR THE STAMINA!!! Basically that's the part where dancers and performers would push to have so it helps with breathing and postureOthers humorously remarked that the group’s upcoming tour would be even more intense after watching the gym vlog. Fans also look forward to the singer's new collaboration with Calvin Klein.Dani💋@InASubBubble @InASubBubbleLINK@dreamjeons If Calvin Klein didn’t make the most body builder Jungkook there’s no justice in this world 🔥🔥ASJ⁷ @jeon_soulLINK@dreamjeons Loosing my sanity over this what will happen when Calvin Klein campaign will drop⋆˙ᵕ˙𓂃★𓂃𝒩ℯ𝓡𝓜ℯ𝓃𓂃★𓂃˙ᵕ˙⋆ @nermenessam71LINK@AboutMusicYT The tour will be crazy with these bodies on stage❤️‍🔥More on Jungkook, Ma Sun-ho’s vlog, and BTS’ LA preparationsThe vlog provided fans with a rare behind-the-scenes glimpse into BTS’ time in Los Angeles, where they spent several weeks completing recording, choreography, and other preparations for their highly anticipated group comeback. Ma Sun-ho, who has been associated with the group through training sessions, served as their personal fitness coach during this period. This gym content arrives shortly after the Golden star's return to public life. A week ago, he attended New York Fashion Week as the global ambassador for Calvin Klein. The event marked his first major fashion appearance since completing service.BTS' Jimin And Jung Kook Discharged From South Korean Military (Image via Getty)He later clarified in a Weverse livestream that while the experience was valuable, such events were not exactly his style. The livestream also gave him a chance to address viral clips from the after-party. He assured fans that his comments had been misinterpreted.BTS as a group is now fully focused on their comeback album, which will be their first release as seven after nearly three years. Each member has been balancing solo activities with preparations for the group’s return.Jungkook, who debuted as a soloist with Seven and GOLDEN in 2023, has stayed a leading figure in both music and fashion.