Attrition in fourth quarter 2012 was 10.4 percent compared to 9.6 percent in the same period in 2011. Excluding the former Lifestyle Family Fitness clubs, the fourth quarter 2012 attrition rate was 10.1 percent.

Trailing 12-month attrition on Dec. 31, 2012, was 38.2 percent compared to trailing 12-month attrition of 35 percent on Dec. 31, 2011. Excluding the Lifestyle clubs, the trailing 12-month attrition was 36.9 percent.

Akradi said Life Time will soon be reporting membership and attrition metrics in two categories: access membership or subscription (bronze and gold tiers) and non-access membership or subscription (platinum and onyx tiers).

"We believe this provides the most accurate reflection of our true attrition rate in our business," Akradi said.

The results released today fall in line with Life Time's preliminary results released on Jan. 31. The company expected 2012 revenue to be between $1.125 billion and $1.127 billion and net income for 2012 to be between $110 million and $111.5 million.

For 2013, Life Time expects revenue to increase 6.5 percent to 8 percent ($1.2 billion to $1.22 billion), and net income is expected to be up 8 percent to 11 percent ($120 million to $124 million).

Life Time will open three new clubs in 2013. The first one was announced Tuesday, in Vestavia Hills, AL, just outside of Birmingham. That club will open in mid-April. Life Time CFO Michael Robinson said the company will open clubs in Reston, VA, and Montvale, NJ, in the second half of this year.

Akradi confirmed the 2014 openings of clubs in Harrison, NY, and Laguna Nigel, CA. Beginning this fall, Life Time will open a new large center every other month, Akradi said.

"Our real estate pipeline for potential new centers in 2014 and 2015 and beyond is filling up very nicely," Akradi said. "Our development and construction group is ready to deliver the unit level growth we are talking about."

Life Time's stock price was $42.80 during midday trading on the New York Stock Exchange.