I admit to a certain fascination for Madonna and, specifically, her body. I relate, undoubtedly, because we are the same age. But it seems I am on one side of a divided world. There are those who want to know how to get her body and those that think she’s gross and exercises too much (in one of our posts, we noted that Madonna packs in three hours of working out a day). The gross camp get most agitated when it comes to Madonna’s veiny arms. Now the veiny arms issue gets me too. Angelina Jolie has them too. But no one accuses Angie of exercising too much. So what’s going on with protruding veins? Well, theories about the cause of popping veins also has the world divided into two camps.

One theory is that over exercising causes veins to pop. The other is that it is due to being under nourished. So which is it?

“Oftentimes when your body fat is really, really, low, as Madonna’s is, you’re going to see veins pop,” Leslie Bonci, director of sports nutrition at the University of Pittsburgh Medical Center told ABC News.  When muscles look that way, it’s often the result of pretty restrictive eating and dehydration.”

I was ready to buy this, especially as it seemed to fit the description of a tad too skinny Angelina. Then I came across a very persuasive counter argument in Scientific America made by Mark A. W. Andrews, professor of physiology at the Lake Erie College of Osteopathic Medicine.

He points out that to explain the prominence of veins during exercise, it helps to understand the vascular system and its components. I’ll spare you that detail. But what is essentially happening is that arterial blood pressure rises during exercise and causes plasma fluid otherwise resting in tiny tributaries to be forced out through the thin vessel walls and into compartments surrounding the muscles. This process, known as filtration, causes a swelling and hardening of the muscle. As a result of this swelling, cutaneous veins are pushed toward the skin surface, flatten to some extent, and appear to bulge.

Andrews adds that this bulging is neither good nor bad but simply a result of normal physiological mechanisms that result from the rise in arterial blood pressure during exertion. He also says that “such veins are more visible in persons with less subcutaneous fat”.

So both theories are right. Madonna has veiny arms because she exercises a lot and has very little extra fat on her frame. There’s another reason why she shouldn’t push her workouts too much – exercising to the point of exhaustion ages you.