One look at the statuesque, toned and always-beaming swimming icon Summer Sanders, and you’d likely never guess what the former Olympian is promoting: varicose vein awareness.It all started on a girls’ day out, when Sanders took her visiting mother to a Park City, Utah spa for facials, where the elder Sanders’ interest was piqued by vein screening and services that were also offered on site. “We got to thinking, if mom was going to come with me to London and really enjoy it and walk around a ton, we should get her veins looked at because they were bothering her,” said Sanders, who will cover the upcoming Summer Olympics for Yahoo Sports.MORE: Your Guide to Gorgeous Skin, Head to ToeWhile the two assumed that mom’s career as a flight attendant was to blame for her varicose veins, Sanders decided to have herself screened after she realized she had been experiencing “heavy-feeling legs.” She would routinely massage her legs at the end of each day since the birth of her son Spider, now four years old.“I go through the day as a busy mom and hardly have time to sit down for a meal, so by the end of the day, I’m like ‘Of course my legs ache! I’ve been on them all day!’” But after her screening, Sanders learned she had Chronic Venous Insufficiency (CVI) like her mom, a treatable disease of which varicose veins are a leading symptom. “I thought, I have to tell people that the face of varicose veins isn’t just grandma like I had imagined,” said Sanders. “It can be a young, athletic person—even an Olympian.”MORE: The Best Proven Way to Treat Varicose VeinsYet that’s not where the misconceptions end. “Varicose veins are often misunderstood as just a cosmetic issue, when it’s really a medical issue,” says Dr. Mark A. Adelman, chief of the Division of Vascular Surgery at New York University Medical Center.Healthy leg veins contain valves that open and close to regulate the flow of blood down the legs, up against the force of gravity, and back to the heart. CVI occurs when stressors to the venous system like pregnancy, a lifestyle of routinely standing for extended periods of time, and age weaken and stretch veins, causing structural damage and affecting blood flow, which results in blood pooling in the legs. Veins then bulge and bubble above the skin’s surface. In fact, those varicose veins are often the first sign that blood flow is disrupted.QUIZ: How Healthy Is Your Body Skin?Varicose veins affect about 30 million Americans, though only ten percent ever seek out treatment. “Usually, there’s a familial predisposition to varicose veins—like Summer and her mom—and then a stressor like pregnancy will push it to the surface,” says Adelman. The condition affects women and men at a ratio of three to one, though thanks to thick leg hair that acts like a vein concealer, men are even less inclined to come in for removal.Other CVI signs include a feeling of heaviness or legs that feel like “water bags,” with progressive disease symptoms including itching and leathery skin around the ankles, and ulcerations where the skin may open up under pressure. “A lot of people blame aching legs on being on their feet all day, but if you’re feeling a rush of relief when you put your feet up every day, it’s a major sign you should get checked out,” says Sanders, adding that you can do a free self-assessment and search for a qualified doctor near you on silver lining is that since varicose veins and the pain they cause are considered a medical condition, most insurance companies cover treatment and removal. However, the condition shouldn’t be confused with thin and superficial spider veins—a separate blood vessel issue that has its own unique causes—which insurance companies usually don’t cover.GALLERY: Best Makeup for Your Body“In the old days, we used to put patients under anesthesia and strip varicose veins out,” says Adelman. “Now we leave the vein in, but destroy it using controlled heat, which is the most effective way to treat today—and you can get it comfortably done in the office with just some numbing.” Known as endovenous thermal ablation, the minimally invasive treatment involves inserting a thin tube into the diseased vein, then sealing it shut with heat, of either the radiofrequency (RF) or laser energy type. Blood that would normally route through the vein simply travels through others instead. The treated vein then dries up and is absorbed by the body.“In terms of pain and discomfort, 95 percent of patients report feeling great immediately afterwards, and 70 percent think their legs look great after one procedure,” says Adelman. “A small percentage of patients come back to have an ancillary procedure to remove some of the veins for complete visual satisfaction,” adds Adelman. According to the doctor, it’s typical for patients of all ages to be back to normal activity by the next day—which was the case for both Summer and her mom, ages 39 and 64, respectively.As for Sanders, varicose veins sure aren’t slowing her down.  While she says, “I no longer want to push myself past my physical limit,” she fits toning into “the cracks and crevices of the day,”—doing sets of push-ups in the morning as her shower water warms up, or tricep dips on the bathtub ledge while waiting for a bubble bath to fill. (Gold medal in multi-tasking, anyone?)VIDEO: Pregnancy and Varicose VeinsAn active lifestyle lover, Sanders rotates between swimming, hiking and running as she feels the urge, most recently taking up marathons for fun. And she’s got a tip for other runners out there. “When I was in the Olympic trials in 1992, I went out way too fast in the first 25 of my 400 meters, and to say that I died at the end is an understatement—it was like the swimmer in second place was pulling and dragging my legs,” says Sanders. “In a distance race of any kind, relax and take those first few minutes slower than you otherwise would. You win by pacing yourself.”