DEFUSE A BRAIN BOMB

Tough day at the office? Work stress can send your stroke risk skyrocketing. A new Japanese study found that men with demanding jobs in which they feel micromanaged have a 2 ½ times higher risk of stroke than men in less taxing positions. Chronic job stress keeps your sympathetic nervous system on high alert, which in turn may push your blood pressure into the red zone, says study author Akizumi Tsutsumi, M.D.

HEAL YOUR HEART

When doctors need to prop open a narrowed artery, they often choose to insert a stent. But sometimes medication can do the same job with fewer risks. To ensure the best heart treatment for yourself or a loved one, ask the surgeon to supplement an angiogram with the “fractional flow reserve” test, which measures blood pressure and flow at the narrowed point. In a recent Dutch study, patients who underwent both tests received one-third fewer stents than an angiogram-only group – and had 35 percent fewer heart attacks over the following year.

DODGE DIABETES

Short bursts of exercise can reduce your risk of diabetes, say Scottish researchers. In their study, men sprinted on a stationary bike for 30 seconds, rested for 4 minutes, and then repeated the routine three to five more times. After six workouts, the men’s insulin sensitivity improved by 23 percent. “High-intensity sprints prime your muscle fibers to respond better to insulin,” says study author James Timmons, Ph.D. If you’re not tiring toward the end of each sprint, you’re bicycling with too little resistance.

KEEP YOUR COOL

Some elite distance runners wear chilled vests prior to a race to delay overheating. Here’s an easier boost: Drink cold water before and during exercise to improve your endurance. In a British study, bicyclists who drank about 30 ounces of a chilled drink in the half hour before riding in a hot, humid environment – and smaller amounts as they rode – were able to bike 23 percent longer than riders who downed lukewarm liquids. Drinking cold water may be the most direct way to reduce core body temperature so that it takes longer for you to heat up and slow down, says study researcher Jason Lee, Ph.D. Keep your workout drink cold by toting an insulated Polar Bottle. ($12, rei.com)

GO FASTER WITH FISH OIL?

We know fish oil is heart healthy, and here’s more proof: Cyclists who took fish oil for 8 weeks had lower heart rates and consumed less oxygen during intense bicycling than a control group did, Australian researchers report. The fatty acids in fish oil need to become incorporated into muscle and heart cells to have an effect, and that takes weeks of consumption, says study author Peter L. McLennan, Ph.D. Future studies will evaluate whether taking fish oil can also speed recovery.

BORN TO RUN

Your activity level may have a strong genetic component, according to a study out of UNC at Charlotte. The scientists found that certain genes in physically active mice appeared to be more involved in regulating activity than the same genes in sedentary mice.

CANINE CLUES

Researchers at Oklahoma State University are studying Iditarod sled dogs to learn hot to train and feed human muscle so it doesn’t fatigue during intense, sustained workouts. The dogs’ muscle fibers adapt rapidly to exhaustive exercise.