Health briefs: Workout time and weight loss

Thirty minutes of daily exercise achieves the same amount of weight loss as 60 minutes, according to a small new study. The research included 60 heavy but healthy Danish men who exercised for either 30 or 60 minutes a day while wearing a heart-rate monitor and calorie counter. The sessions were designed to generate a light sweat, but participants were expected to boost the intensity three times a week. Those who exercised 30 minutes a day lost an average of eight pounds over three months, compared with six pounds for those who exercised 60 minutes a day.

Yo-yo dieting

So-called "yo-yo" dieting -- where people repeatedly lose weight by dieting, only to regain the weight -- may be frustrating, but it will not hurt a person's ability to lose weight over the long term, a new study from Fred Hutchinson Cancer Research Center in Seattle finds. This type of "weight cycling" does not have a negative effect on metabolism, the study found. The findings may be significant, the experts added, because yo-yo dieting affects up to 40 percent of the population in the Western world.