Enjoy this tease of warm weather; After Tuesday we’re back to highs in the 40s, lows in the 20s.  According to Gary Sforzo, a professor of exercise and sports sciences at Ithaca College in New York, the return of cold weather shouldn’t deter you from exercising.

“If you are concerned about hypothermia, you don’t need to be unless the temperatures are extreme,” advises Sforzo. “The body produces a lot of heat during exercise and when it produces heat, it pretty much diminishes any chance of hypothermia. “The key is continuous exercise. If you go outdoors for a walk or run, just move continuously. Don’t stop for five or 10 minutes to talk to your neighbor. Hikers sometimes get into trouble if they stop for lunch. As long as you are moving, the muscles produce metabolic heat and that metabolic heat will keep you pretty warm… .” So even if you bundle up http://www.youtube.com/watch?v=HW4IZ0Flh3M for the cold, you may end up shedding layers. He adds: “The danger zone is typically in the -20 to -30 windchill zone.”

That, hopefully, is something we won’t have to worry about.

Exercise and baby weight

Exercise during pregnancy is good for mom and baby, but it doesn’t have an impact on how much a baby will weigh at birth, according to a study by the Norwegian Institute of Public Health. The institute studied the exercise habits before and during pregnancy for 43,705 women ages 15 to 49.

The exercisers in the study — defined as those who “reported brisk walking, jogging, bicycling, aerobics, fitness or weight training, or other physical activities an average of 6 times a month during the first 17 weeks of pregnancy and then 4 times a month until week 30” — gave birth to babies that weighed about the same as the women who did not exercise.

The study did, however, find that women deemed overweight or obese before getting pregnant gave birth to heavier babies. Concluded the study’s administrators: Exercise and drop that extra weight before getting pregnant.

Mexican-Americans most active

Mexican-Americans are doing a better job of meeting minimum physical activity goals than whites or blacks, according to the National Health and Nutrition Examination Survey. Among other things, the study tracked 10,000 people in the U.S., each of whom wore an electronic device that tracked their activity levels. The survey found that 27 percent of Mexican-Americans met the goal of doing either 30 minutes of moderate exercise five days a week, or 20 minutes of rigorous exercise three days a week. Twenty percent of whites met the goal as did 15 percent of blacks. The findings were published online Feb. 11 in the American Journal of Public Health.

Curiously, previous studies found that physical activity target was reached by 36 percent of whites and 25 percent of blacks and Mexican-Americans. Those studies, however, relied on self-reporting.

“Those self-reported findings … show that people are likely to have difficulty estimating their activity levels,” said study author Sandra Ham, a graduate student at the University of Chicago.