Jim Cramer's Mad Money In-Depth Stock Picks, Jan. 31

Stocks discussed in the in-depth session of Jim Cramer’s Mad Money TV program, Wednesday January 31. Click on a stock ticker for more analysis:

Life Time Fitness (LTM) and Town Sports (CLUB)

Since many people make New Year's resolutions to lose a few pounds, the time period between January and March is a good time to own fitness companies, says Cramer who chooses LTM as his "No. 1, best-of-breed, health club pick." He prefers LTM to CLUB, because it has better operating margins, higher revenue per customer and is not costly. In addition, Cramer comments that LTM has better and larger clubs and a superior business model. In spite of Prudential's negative rating, Cramer believes that LTM is a buy, regardless of the money the company will have to spend as it expands into wealthier areas, since the gym then will be able to charge higher prices.

Related: Tate Dwinnell considers LTM a healthy long-term investment.

Yo-Yo Diet Stocks: NutriSystem (NTRI) and Weight Watchers (WTW)

Cramer commented that NTRI has gotten "crushed" because of its awful guidance; it was "flying high, then got pounded." He says that this stock is not safe to buyand is a "one-hit wonder," since its customers tend to abandon the product after 10 weeks, and everyone knows about the company. Cramer prefers WTW for growth and customer loyalty.

Related: Notable Calls comments that Citigroup is confident in NTRI's long-term prospects.

Mad Mail: Waste Services (WSII)

When asked how to buy WSII with a limit order, Cramer gave guidelines on how to respond to his picks, and discouraged viewers from buying stocks on the night he discusses them. Day one, an investor should do homework, day two, wait for other investors to give up and throw away the stock, and day three, do a mon' back (buy).

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