A U.C. Davis study says low-wage workers just can't get ahead.

Researchers say those who are just getting by know the different ways to increase their skills and go for higher paying roles, but their working conditions essentially make progress impossible.

Long hours make things difficult, and many of the subjects interviewed -- first generation immigrants -- say they're working multiple part-time positions to provide for family members.

Some are expected to be on call at any time -- a roadblock to education.

The UCD team makes an argument for living wages and other worker protections, like some guaranteed hours each week.