Mark Mastrov and the Founding of 24 Hour Fitness
Mark Mastrov co-founded 24 Hour Fitness in 1983 in San Bernardino, California. The gym chain grew into one of the largest privately owned fitness center operators in the United States. Mastrov served as CEO and built the brand around extended hours and a no-commitment model. The company operated over 400 locations across the U.S. at its peak, serving millions of members annually source.
Mastrov sold a majority stake in 24 Hour Fitness to private equity firm AEA Investors in 2014. The deal valued the company at approximately $1.6 billion. After the sale, Mastrov transitioned to a chairman role while remaining involved in strategic decisions. The ownership structure later shifted again when AEA brought in additional capital partners to fund expansion and acquisitions source.
Bankruptcy, Closures, and Restructuring
2020 Bankruptcy Filing and Store Closures
24 Hour Fitness filed for Chapter 11 bankruptcy in June 2020, citing pandemic-related shutdowns and unsustainable debt. The company listed assets and liabilities between $1 billion and $10 billion. Mastrov was not the primary debtor in the filing, but the company he co-founded was the central entity. The bankruptcy led to the closure of hundreds of locations nationwide, reducing the footprint by more than half within months source.
After emerging from bankruptcy in late 2020, 24 Hour Fitness operated under new ownership with a significantly smaller network. The restructuring eliminated underperforming clubs and renegotiated lease obligations. Mark Mastrov had no formal executive role in the post-bankruptcy entity. The company focused on reopening core locations in high-density markets across the U.S. source.
Current Status and Market Position
Ownership and Operations Today
24 Hour Fitness is currently owned by a group of institutional investors following the bankruptcy restructuring. The chain operates a reduced number of clubs compared to its pre-2020 peak. The brand continues to offer multi-club memberships and 24-hour access at participating locations. Mark Mastrov is no longer affiliated with the company in any operational or executive capacity. The fitness industry remains highly competitive, with chains like Planet Fitness and Equinox dominating different market segments source.
The post-bankruptcy 24 Hour Fitness targets price-sensitive consumers with lower monthly fees than premium competitors. The company emphasizes convenience and extended operating hours as core differentiators. Membership numbers remain undisclosed, but the reduced location count suggests a smaller member base than in prior years. The brand continues to face challenges from rising labor costs and shifting consumer preferences toward boutique fitness and home workouts