More Anytime Fitness members worked out late at night, cashed in on health insurance reimbursements and made March the busiest workout month in 2011, according to statistics in the Hastings, MN-based company’s second annual Weight of the Union report.

The study, which examined the fitness and nutritional habits of 1.3 million Anytime Fitness members, found that the 24-hour key-card clubs had totaled more than 52 million workouts in 2011, an increase of one million workouts from 2010. There also were 1.2 million workouts from midnight to 3 a.m. at Anytime clubs, an increase of 300,000 workouts in the same time period from the previous year.

The busiest month for Anytime Fitness members was March, not January, according to the study. More than five million members worked out at Anytime Fitness in March compared to four million in January.

“The obesity epidemic in this country continues to rise, and Americans need to get serious about health and wellness,” said Chuck Runyon, CEO of Anytime Fitness and co-author of the new book “Working Out Sucks.” “While our Weight of the Union report gives a good snapshot of our more than 1.3 million members, and it is encouraging to see our members continuing to take charge of their lives through fitness and nutrition, there is still more work to be done.”

In other findings from the report, Anytime Fitness members received almost $4 million in health insurance reimbursements for working out 12 or more times a month, an increase of $1 million from 2010. More men visited Anytime Fitness than women (54 percent to 46 percent) in 2011. Also, the most popular day of the year to work out was March 28, and the least popular day was Dec. 25.

The top five states with the highest average Anytime Fitness member visits per year were New Hampshire (54 visits), Minnesota (53), Delaware (49), Vermont (49), and Iowa (46).

Anytime Fitness has more than 1,800 clubs in 50 states and 11 countries.