Energy companies are struggling as oil prices fall, and some are in worse shape than others. Real Money has picked out four companies to put on its ‘Stressed Out’ index, including Chesapeake Energy (CHK), Southwestern Energy (SWN), Ultra Petroleum (UPL), and Encana (ECA). To make the ‘Stressed Out’ distressed watch list, companies carry unsustainable debt loads and have a history of burning cash and resources. Just a few days ago, Chesapeake suspended its preferred dividend payments, and other companies on the ‘Stressed Out’ index are laying off workers or facing high debt costs. Carleton English, a writer and analyst with TheStreet’s portfolio products, says investors shouldn’t be lured by the companies’ low stocks prices.