More fit equals less fat, public health researchers agree

Public health researchers have stumbled on the science behind the reason those marathon runners appear to lack even a gram of body fat: It's not just that they run for 20 some miles at a time. It's that they can run 20 some miles at a time. According to a new public health study, people who are very fit actually release more fat-burning molecules - called metabolites - in their blood following exercise compared to lesser fit people who perform the exact same exercise. In other words, public health experts now say, you get better at burning fat with each gain you make in your fitness. It's the ultimate motivation for those among us who exercise once or twice a week and then wonder why we still jiggle when we walk.

The study looked at how common exercise changes metabolism at the level of chemical changes in the blood. To measure the fat-burning molecules, public health researchers took blood samples from exercisers before, immediately following, and then after an exercise stress test that was about 10 minutes long. Then they measured the blood levels of 200 different metabolites, which are released into the blood. According to the public health study, after running on a treadmill for 10 minutes, people who had a greater level of fitness had a 98 percent increase in the breakdown of stored fat, sugar, and amino acids, while less-fit people had only a 48 percent increase.

"Every metabolic activity in the body results in the product of [fat-burning] metabolites," public health senior study author Dr. Robert Gerszten, director of clinical and translational research at Massachusetts General Hospital Heart Center, told Health and Human Services' HealthDay. "A blood sample contains hundreds of these metabolites and can provide a snapshot of any individual's health status." The most fit people had the greatest level of metabolites: Blood samples taken from 25 people before and after they ran the 2006 Boston Marathon found a 1,128 percent increase in some key metabolites, according to HealthDay. The study may have future implications for the treatment of diabetes and other health conditions.

Not quite at the level of the Boston Marathon? Here are tips for healthy living and for taking your fitness up a notch:
* Health care experts agree that consistency is key. To become even moderately fit, you must exercise several times a week. Some public health studies even suggest that people with sedentary lifestyles or jobs need to exercise 60 minutes a day in order to control or lose weight.

* Join a recreational sports team. Many cities, even smaller, rural areas, offer recreational sports teams for softball, volleyball or soccer. Not only do these activities offer a chance to get your heart rate up, they will inspire you to add additional jogging and strength training to your repertoire - especially after the first time you pant your way around the bases.

* If you live in a larger city, very likely you can find coached group exercise sessions for running, swimming and biking. The price is reasonable - maybe $10 or less per weekly session - and you will push yourself harder during the coached sessions than you do on your own. You also will be inspired to add more workouts during the week out of fear of falling behind during the group sessions.

Photo Credit: Sheffield Tiger