Does Weightlifting Cause Varicose Veins?

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If you've ever done a set of heavy back squats, you've probably noticed that the veins in your legs become more pronounced right after. You might conclude that lifting causes varicose veins, which are veins characterized by their bulge-y appearance (more on that below). But does lifting actually cause varicose veins?

I took my question to a few doctors and fitness experts to get the lowdown. Here, they explain what varicose veins are, what causes them, and how varicose veins are different from a post-workout pump.

What Exactly Are Varicose Veins?

Varicose veins are enlarged, blue veins (often found in your legs or feet). They often look "blue, abnormally enlarged, and bulging, with rope-like blood vessels, almost like a cluster of grapes," says Antonios P. Gasparis, M.D., director of the Center for Vein Care & Vascular Lab at Stony Brook Medicine.

To understand varicose veins, first you have to understand how blood moves through the body: Your arteries carry blood away from your heart and to your tissues (including your muscles), and your veins carry the blood in one direction—back to your heart—explains Jennifer Reichel, M.D., of Pacific Dermatology.

Normally, valves in the veins prevent backward blood flow, says Alejandro Badia, M.D., board-certified hand and upper extremity orthopedic surgeon. "But when the valves are weak or damaged—called venous reflux—the blood can flow in both directions." This causes the blood to pool into the veins, which creates the enlarged appearance associated with varicose veins. While varicose veins are most commonly seen in the legs (because of gravity), they can be found on various parts of the body.

The good news is that beyond the aesthetic concern, the majority of folks don't experience any accompanying symptoms. (But when they do, heaviness in the legs and muscle cramping are the most common.)

What Causes Varicose Veins?

The number-one cause of varicose veins is genetics. "I see hundreds of patients with varicose veins every year, and the vast majority have developed these veins because of a genetic predisposition to forming varicose veins," says Allan W. Tulloch, M.D., vascular surgeon at Providence Saint John's Health Center in Santa Monica, CA. Ugh, thanks Mom.

Other contributing factors include hormonal changes during pregnancy or menopause, aging, history of venous blood clots, and obesity, he says.

People who are less active are more likely to get varicose veins, too, says trainer Jacqueline Kasen: "People with sedentary jobs have a lack of blood circulating throughout the body, which puts them at an increased risk." (Related: 9 Things That Are Better for Your Body Than Standing Desks)

Does Lifting Cause Varicose Veins?

Nope. "It's easy to infer that weightlifting will cause varicose veins since sometimes our veins pop out during exercise, but that's not the case," says Michael Richardson, M.D., a One Medical provider. As seen above, there are a number of factors that may increase your chances of getting varicose veins, but Dr. Richardson says, "Exercise and lifting weights are not one of them." (Phew).

In fact, because exercise increases circulation, it's often thought of as a preventative measure against varicose veins, says Kasen.

However, according to Dr. Tulloch there's one caveat: When you lift really heavy weights—like a one-rep max back squat, for example—you put a lot of demand on your muscles, which puts a heavy demand on your veins to get the blood back to the heart. "You're also potentially bearing down and increasing the amount of pressure in your venous system, which over a long time could lead to weakened valves and therefore varicose veins in individuals who are predisposed to their formation."

But he says proper lifting technique can help ward against this. If you're lifting heavy often, consider using compression socks to help with blood flow, says certified personal trainer Alonzo Wilson, founder of Tone House in New York City. (But BTW, most trainers like Kasen say you shouldn't be testing your one-rep maxes more than once a month, anyway. Here's how often you should be lifting heavy.)

If you already have varicose veins and are experiencing severe symptoms, some doctors may advise you to cut back on the heavy-heavy lifting. "But when patients with varicose veins who aren't in pain ask me whether they should continue to exercise, my answer is always yes because exercise is so important for a healthy lifestyle," says Dr. Tulloch. (Seriously—here are the many health benefits of lifting weights.)

The Difference Between Varicose Veins and "The Pump"

If varicose veins aren't caused by lifting, why do your veins stick out after you've been lifting weights? "The post-workout 'pump' isn't caused by faulty valves, the way varicose veins are," says Dr. Tulloch.

"When you lift, the muscle tissue that you're working requires an increase in oxygen, which they get from blood from your arteries" explains Dr. Richardson. Since more blood is being sent to the muscles during physical activity, your veins have to carry a larger amount of blood too.

"But because your veins require gravity to carry the blood back to the heart, this happens slower than the arterial inflow," explains Dr. Reichel. This can cause a "backup" of blood in the veins and increased pressure in the veins. The result of this increased pressure is that the veins "pop."

There are other factors that play a role in the pump, too: the type of exercise you're doing and genetics. (Related: Forget Diet and Exercise—Do You Have the Fit Gene?)

"When you work out, your muscles swell, which pushes the veins closer toward the skin's surface and adds to the appearance of bulging," says Dr. Gasparis. In general, he says strength training will trigger the pump more so than light cardio—due to something he calls "muscle loading," or muscle fatigue.

And, yep, as with most things in life, your genes play a role. "Some people are born more vascular than others," says Dr. Gasparis. However, it can depend on your body composition too: "The less fat a person has, the more visible the veins appear," he says. So after the same workout, someone with 13 percent body fat, for example, might appear more pumped than someone with 28 percent body fat, even if the same process is going on physiologically.

TD;LR: While varicose veins are considered permanent and have a number of causes, the post-workout pump is temporary and is a result of the normal physiological things that happen in your body during and after exercise.

The Bottom Line

"I wouldn't avoid weight lifting out of fear that it could cause varicose veins, because it can't," says Dr. Richardson.

Guess I'll see you at the weight rack! Or maybe in the locker room, checking out my arm pump. *Wink*.