No word yet on if this is a majority or minority investment, as TSG is known for doing both. Fairly likely, however, that Planet Fitness senior management will stay in place.

Pierre LeComte, a San Francisco-based partner with TSG, is leading the transaction. It doesn’t look like he has any particular experience in health clubs but, then again, neither does TSG. The firm has been investing in “middle-market branded consumer companies” since 1987, but the vast majority of current deals are either are for products (personal care, pet care, car care, apparel, food, beverage) or restaurants.

Planet Fitness is based in Dover, N.H., and has more than 400 owned and franchised locations (mostly in the U.S.). Many of those came to Planet Fitness via a 2006 acquisition of World Gym International, which was supported by a $3 million subordinated debt investment from Prasidian Capital. The company focuses on a low-key, “judgment-free” environment, even going so far as to oust customers who grunt while lifting weights.

I’ve put in calls to both TSG’s LeComte and Planet Fitness CEO Michael Grondahl, and will update this post if they call back.

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