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What: Shares of Life Time Fitness, (NYSE: LTM) were in need of a new workout plan today, falling as much as 15%, and finishing down 13% on a disappointing earnings report this morning.

So what: It was a triple whammy for the fitness center operator as it missed revenue and earnings estimates, and lowered its guidance. Life Time said revenue ticked up 6% in the quarter, to $326.7 million, short of the consensus view at $332.2 million, as total memberships improved just 1.2% in the quarter. On the bottom line, earnings actually fell, as increased gym operating costs ate into the additional revenue, and profit per share fell from $0.80 to $0.76. Analysts had expected an EPS of $0.81.

Now what: CEO Bahram Akradi called the quarter "a challenging one for our company as we faced unexpected erosion of membership levels at some centers." Still, he said newly opened centers had outperformed expectations. As a result of the poor performance, management reduced revenue guidance from $1.3-$1.32 billion to $1.29-$1.31 billion, and lowered its EPS outlook to $3.00-$3.10 from $3.05-$3.15. The revised projections were still in line with the analyst view at $3.08 in earnings per share and $1.31 billion in revenue. The fitness center industry overall has been weak lately, perhaps owing to the rise of yoga studios and other alternatives such as Crossfit. If that trend persists, I'd expect more tough times for Life Time.