Episode 6 of "Pump Up the Healthy Love" kicks off with Mi-ran pounding away on the treadmill, her mind an endless loop of Joon-seok's deleted message. Her determination borders on obsession, culminating in a catastrophic breakdown of the treadmill. This unexpected mishap plunges the staff into a financial quandary; replacing the machine is an expense they can't afford.
Desperate for a solution, they hatch a plan to bolster their funds by encouraging members to enroll in personal training sessions with Hyeon-joong. With a bold 30% discount banner hanging prominently, optimism fills the air—yet, surprisingly, no one bites. Mi-ran even goes the extra mile, trying to persuade the trio of gym regulars, with Seong-im eventually succumbing to her charm and signing up. A jubilant Mi-ran and Hyeon-joong share a high-five, during which he notices her calloused hands—a testament to her dedication to fitness. He thoughtfully gifts her hand cream, adding a touch of kindness to their bond.
Returning home on a cloud of excitement, Mi-ran's spirits deflate upon finding her sister in tears. Kang Dan has called it quits, citing his overwhelming happiness as a distraction from his songwriting. Determined, Mi-ran vows to support her sister through this heartbreak.
Seong-im's training sessions with Hyeon-joong commence with boundless enthusiasm, her inquisitiveness knowing no bounds. She eagerly soaks up every piece of advice, eager to make the most of the gym's 24/7 access.
At work, a pleasant surprise awaits Mi-ran—her Hawaii-themed show has become a smash hit. Ye-jin drops a bombshell revelation: it was Joon-seok who lobbied for Mi-ran to host the live broadcast.
Post-work, Mi-ran brings Ji-ran to the gym, where Hyeon-joong, recognizing Ji-ran from the photobooth incident, attempts to duck his identity. In an effort to impress her younger sibling, Mi-ran overextends herself physically. Hyeon-joong swiftly comes to her rescue, smoothing over her novice misstep with a machine she's unfamiliar with.
At a particular moment, Seong-im initiates a dusting session in the office, inadvertently causing the shattering of Hyeon-joong's trophy. To compound the situation, Hyeon-joong discovers that his muscles are atrophying due to Seong-im's strict prohibition on his workouts. The following day, Seong-im treats Hyeon-joong to a meal, during which he prepares to confide something in her. However, her world shatters when she catches sight of her husband with another woman. Seeking refuge, she turns to Hyeon-joong, who complies with her request. She later confides that, despite her husband taking her for granted, she refuses to divorce for her daughter's sake. She loathes being at home, which is why she finds solace in the gym and cherishes the attention Hyeon-joong lavishes on her.
While working out, Hyeon-joong ponders the intricacies of his situation. Meanwhile, at home, Ji-ran reveals to Mi-ran that her workouts have been a distraction from thoughts of Kang Dan. In the morning, Mi-ran shares with Hyeon-joong how exercise has bolstered her spirit. In response, Hyeon-joong introduces Seong-im to a specific exercise designed to ease shoulder tension and encourage letting go. Seong-im grasps the underlying message and admits that severing ties with family members is easier said than done.
As the trio ventures out for a meal near the gym, they encounter Seong-im's husband with his mistress. Brazenly, he introduces the woman as a colleague and audaciously asks Seong-im to prepare her a meal. At this point, Seong-im's patience snaps. Hyeon-joong hands her a resistance band, which she uses to deliver a resounding slap to her husband's face. Mi-ran pitches in, tripping him, and as he hastily retreats, the gym entourage celebrates with drinks. On their way home, Mi-ran and Ji-ran assist a garbage collector, and it's then that Mi-ran spots Joon-seok approaching. She ducks out of sight and asks Ji-ran to inquire about some text messages he had sent.
Ji-ran comes to a stark realization: Mi-ran has been unable to truly part with Joon-seok. Desperate, she reaches out to Kang Dan, pleading with him to reconsider his departure. Meanwhile, Mi-ran finds herself in a depths of despair, her distress deepening upon discovering that one of her calluses has shed, a symbol of her hard-earned progress now slipping away. Seeking solace, she heads to the gym where she unburdens her sorrow to Hyeon-joong, tears streaming down her face.
In a poignant epilogue to Pump Up the Healthy Love Episode 6, Joon-seok finds himself entranced by the sight of Mi-ran weeping on the street, his gaze fixed on her vulnerability. However, his moment of introspection is abruptly shattered when he's caught staring by Seong-im, who mistakes him for a voyeur with ill intentions.
