The Pulse: January 2004

Jet-Set Fitness

Warm Up 'Dem Chilly Dogs

If you're a finicky skier who wants toasty toes, stop fiddling with that aluminum foil and insert a pair of Shock Doctor's HotBeds into your ski boots. Made of the same material—a porous solid called aerogel—used in NASA space suits, the new HotBeds are just 2.5 millimeters thick but purportedly insulate as well as eight millimeters of 200-gram Thinsulate or four inches of fiberglass wall insulation. The svelte profile shouldn't compromise fit or performance. And they're less messy than dumping cayenne into your socks. ($20,

A Whey Better Protein

There's nothing new about protein bars (think Zone and Atkins). Nor is there anything new about whey (think curds and tuffets). But a study published in the Journal of Nutritional Biochemistry in May 2003 notes that whey is one of the best forms of protein for athletes. Whitecoats reviewed five years of data about the protein in question—which is separated from curd during cheese-making. The results? Dry whey protein enters the bloodstream more quickly than other protein sources, curbs muscle breakdown during exercise, stimulates recovery and muscle buildup, and bolsters the immune system when it's run down by heavy exertion. Whey protein is, of course, widely available as a powder, but there's also a whey-based snack bar: Grab a Detour (they're each packed with 30 grams of whey protein) and see if your inner brute can feel the difference. (

Why Penguins Never Get Sore

Instead of an après-ski Coors and soak in the hot tub, try this: Fill your bathtub with six inches of ice water and hop in. The chilly soak constricts vessels, pumping out lactic acid. When you get out, the rush of fresh blood back to the muscles reduces soreness and quickly rebuilds fatigued muscles. "Getting into the ice bath right after an intense workout, when your muscles are inflamed, is your best bet. Ten minutes will make your legs springy the next day, says Becca Blay, personal trainer and pro mountain-bike racer. "Or you could just take another shot of tequila and roll in the snow.