You started an intensive weightlifting program to pack on pounds of muscle in a month. Halfway through though you notice red, sometimes purple, lines streaking across your pecs and at the apex of your armpit and biceps. It's not an allergy to the gym or a rash—it's stretch marks.
What is a stretch mark?
"A stretch mark is really an absence—basically a hole in your dermis," says Michael Swann, MD, a dermatologist in Springfield, MO, who specializes in skin cancer, reconstruction, and cosmetic procedural dermatology. Think of a balloon. When you blow it up or stretch it, at some point before the balloon rips apart you’re going to see the material fade in color, get super thin, and bubble or ripple," Swann explains. That’s what your skin does.
Stretch marks are weaknesses in your skin because too much tension has been placed on it for too long. "Our skin is living and active, so it’s constantly responding, so when you put stretch on it, it grows; but it can only do so much before it can't keep up.
It's not a scar, though. A scar is a healing response, Swann explains. That's your body providing extra collagen to bolster a weak spot or wound.
Why they appear
You can get stretch marks as a child just with growth. "If you’re not factoring in weightlifting or bodybuilding, puberty is the big time for guys to get stretch marks because that’s when the most growth is happening," Swann explains. Stretch marks tend to appear when there's a testosterone surge, because that's when guys typically grow taller, bigger, and wider.
The reason you don’t hear older guys over 40 complaining about stretch marks is because they can’t grow that fast, or put on the kind of mass that would stretch their skin. "They can’t turn their arms into tree trunks in two months," Swann says. "The hormone levels aren’t the same even if they’re using supplementation, eating right, and training the same as a younger guy."
Are some people more prone to stretch marks?
You might find solace knowing there’s practically no one who doesn’t get them. Everyone can get stretch marks if the skin is being stretched enough and at the right pace, Swann says.
It all has to do with the composition of collagen in the skin. But, some skin types don’t really seem to get stretch marks; or, the marks can be imperceptible. "I won’t say there’s a perfect skin type for minimizing the appearance of stretch marks, but it’s typically people with less red tones in their skin, who are very fair in complexion," Swann says. There's a caveat in redheads, though. Even though these individuals have fair skin tones, they have a lot of blood vessels in their skin, so they're more prone to having red or pink stretch marks, he explains.
Obviously stretch marks are common in women who are pregnant, but anyone who gains a lot of weight can experience the emergence of marks. "Men, especially bodybuilders, when they’re doing a big anabolic push, growing a lot, doing two-a-days, putting on a ton of weight, tend to get them on their arms, chest, even backs," Swann says.
Guys who are more at risk are the ones everybody envies in the gym (until they get stretch marks, that is): rapid growers. These are the guys who can put two months into a training program and see results instantaneously. "The bulk is crazy, they’re eating like a horse, they’re growing fast and you just can’t believe how big they’re getting," Swann says. "But there’s only so much skin on your body; when your muscles get to a certain size, your skin is going to stretch."
Where do they appear in men VS women?
"Mostly, I see men with stretch marks on their proximal arms (front of the shoulder, by the biceps and armpits) on their chest, backs, and even on the upper thighs," Swann says. Women tend to get them on the sides of their abdomen when they’re in the last trimester of pregnancy, as well as their inner thighs and hips.
Do cocoa butter or Vitamin E work?
Sorry, but no. "There’s no merit to it," Swann says.
"Vitamin E came about as a solution before we understood proper wound care for skin after surgery," he explains. Forty years ago, a study came out that found if you broke vitamin E capsules on a healing wound, the skin would recover better. "The skin really did heal better than the traditional way of letting air get to it or using hydrogen peroxide on it. But it’s not because of the vitamin E; it’s the oil," Swann says.
Keeping dry air away from a wound is just as helpful as using Vitamin E. In theory, you can use Vaseline; you just need to keep the skin moist and hydrated. But, this is in reference to a wound, not a stretch mark. They're similiar, but not the same. "Stretch marks are durable wounds—wounds under the skin at the deeper layer in the collagen," Swann says. It's very difficult to get something there that will make a substantial contribution to healing.
Cocoa butter has been touted as the stretch mark eliminator—passed on anecdotally from woman to woman during pregnancy. But there’s nothing particular to cocoa butter that makes it better than any other moisturizer. Hydrated skin may hold up better against stretch marks since dry skin is less elastic, but it's not a foolproof plan.
Procedures that reduce appearance
There are treatments that work to minimize the appearance of stretch marks, but they're not perfect. The reason being: You can’t cure stretch marks.
That said, the best treatment for stretch marks, Swann says, is a series of carbon dioxide laser treatments aimed at the skin. Your skin has an inflammatory reaction in response to the lasers, which heals and improves the appearance of stretch marks. "You get some lattice-y scar that’s laid down so you can’t really see it from the top," he explains. "These treatments improve the vigor of that deep layer of skin and makes the stretch mark less obvious."
Another option is Ultherapy, a treatment Swann offers in his office. It's essentially skin tightening. "We take a fractionated heat beam and burn a tiny hole deep in the fascia, not on the top of the skin, and depending on what we’re treating, we can tighten the turkey wattle in the front of someone’s neck, problem areas with loose skin, and treat stretch marks to a certain degree, but the results aren't amazing for the marks," Swann admits.
Ways to prevent or minimize risk
The main problem is your skin can’t keep up with the stretching—with the bulk—so easing into a training program is hugely advantageous. "Before you get huge, help your skin acclimate [by taking it slow] so it’s not being stressed in such a small timeframe," Swann says. (Yes, this works for pregnant women and bodybuilders alike.)
Put your focus on your weaknesses, too. "A guy with naturally big pecs might just want that to be his thing—a colossal chest," Swann says. If you're comfortable and easily add bulk to your chest and think 'I'm really good at this, so I’m going to spend all my time doing flyes and bench,' you could up your risk. That's because being well-rounded is key to preventing stretch marks in the first place, or preventing more from showing up. Obviously they’re not mutually exclusive; you can get stretch marks and be well-rounded. But the patients Swann sees with the worst stretch marks tend to train all in one area. They're biceps-chest guys. You're stressing the skin right above your armpits—stretching one way with biceps exercises and the other way with chest exercises, so it takes a toll," he explains.
So, break your workouts up so you're honing in on all your muscle groups. And put some time between your upper body workouts. It'll relieve some strain on your skin—and muscles.