DIET season is here, and three well-known bulge-busting companies  Weight Watchers, Nutrisystem and Jenny Craig  have made major changes in their programs for consumers looking to shed weight packed on during the holidays, or before.

The diet purveyors are jockeying for a share of the rich industry, estimated at $60 billion or more yearly, by ramping up their marketing to showcase new weight-loss approaches like an electronic activity tracker and food upgrades.

And for those who detest counting calories, there may be a shortcut to a svelte figure. The sports apparel makers Fila USA and Reebok International are offering specially engineered body-toning wear that they say makes exercise  and even everyday movement  more efficient, and allows the wearer to look good while doing it.

For the millions who do embark on diets, Weight Watchers International has a new PointsPlus program, its biggest change in the last dozen years in how calories are counted. Nutrisystem North America has spruced up its packaged meals program by offering fresh-frozen foods. And Jenny Craig introduced a program to allow dieters to monitor calorie intake and physical activity levels, which it says is the biggest innovation in its 27-year history.