I do cardio workouts for at least one hour 5-6 days a week and weight training 2-3 times a week for 20-30 minutes. My problem is my feet. I have doubled up on good athletic socks and have also begun putting Vaseline on my feet to help stop blisters. I've tried many shoes; I need help!

--abbyf96

Ah, the agony of de feet! Blisters are among the most debilitating minor injuries an athlete can get. A tiny little blister can keep you on the sidelines for days.

Blisters are caused by friction (heat), so eliminating friction is the key to preventing them. Using Vaseline is a good way to try to prevent blisters, but you're better off trying to get at the cause rather than treating the symptom:

• When you buy new shoes, make sure there's ample room in the toe box area in the front of the shoe. Your toes shouldn't touch the front of the shoe or be cramped together like sardines in a can because the toe box isn't wide or tall enough. When in doubt, go for a bigger size rather than buying a pair of shoes that feel a little snug even before you start bouncing around in them.
• Going to a larger size can also pose problems. Shoes get slightly wider as they increase in size. The next size up may give you room in the toes but less support around your instep, or they may not hold your heel snugly enough. When this is the case, use a flat insole like the ones made by Spenco or Dr. Scholl's to take up some of that extra room.
• If going up a size still doesn't help your problem, try sneakers made by New Balance. They make shoes in widths so you may be able to find a shoe that's got the room you need without buying a larger size.

There are a couple of potential drawbacks to doubling up on socks. First, the extra pair of socks may make your shoes fit too tight. Second, starting, stopping and changing direction can cause two pairs of socks to bunch up in your sneakers, causing a hot spot, rubbing, and possibly ... blisters. Instead, choose socks designed for the activity you participate in by companies like Thor-Lo and Wigwam. For instance, I find that the Thor-Lo cross-training socks are a little thinner than their tennis or running socks, but more cushioned than their cousins the Thor-Lo walking socks.

When you have a blister, keep it clean and don't pop it. If it fills up with blood, have an MD look at it. You can protect a blister while exercising by using a doughnut. Cut a hole in a disk of Dr. Scholl's Mole Foam. Make sure the hole is large enough to encircle the blister without touching it. Tape the doughnut in place using athletic tape. With the blister protected, you can do a little training.

When all else fails, take up swimming.

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