La Gymnastique is a gym owned by Donna-Marie Quinn, with Grace Black serving as a silent partner. The building was formerly pâtisserie Salon de Thé de Marnie, which Donna-Marie inherited from Marnie Nightingale when she was killed in the Salon de Thé explosion in January 2022. Donna-Marie ultimately decided to open a gym, with Grace helping financially due to La Gymnastique being the only gym nearby. Donna-Marie hired Leela Lomax as manager, and also hired her son Romeo Nightingale (who came up with the business's French name as a tribute to Marnie), to work at the gym.
In September 2022, the day before La Gymnastique's grand opening, James Nightingale and Norma Crow orchestrated a break-in, which led to Leela being knocked unconscious and hospitalised. Despite this, at Leela's insistence, La Gymnastique opened as planned.