Athletes paint their nails black for a surprisingly wide range of reasons, from protecting against infection to sending signals to teammates to making a personal statement. The trend has exploded in recent years across football, track and field, soccer, and combat sports, but each athlete typically has their own specific motivation. Here’s what’s behind it.
Protecting Nails From Damage and Infection
One of the most practical reasons is physical protection. MMA fighters popularized black nail polish as a way to harden toenails and prevent them from cracking or splitting during training and competition. Cristiano Ronaldo adopted the same practice, painting his toenails black to shield them from the warm, moist environment inside cleats and training shoes, where fungal infections thrive easily.
There’s some science to support this. A small-scale study cited by Britain’s Royal College of Podiatry found that nail varnish can protect healthy nails from infection, though there isn’t yet a professional consensus on the benefit. For athletes who spend hours in sweaty footwear, even a marginal layer of protection against bacteria and fungi is worth the effort. Black happens to be the color that hides dirt and scuffing best, which is partly why it became the default over brighter options.
Catching Signals in Baseball
In baseball, painted nails serve a completely different function. Catchers paint their fingernails bright or contrasting colors so pitchers can read their hand signals from 60 feet away. Before every pitch, the catcher squats behind home plate and flashes a sequence of finger signs between their legs to call the pitch type and location. Under stadium lights or in day games with shadows, bare fingernails can be nearly impossible to see.
Catchers originally used white-out or athletic tape, but those were messy and impractical. A specialized product called Game Signs, invented in 2010, eventually gave catchers peel-and-stick signal stickers in bright neon colors designed specifically for visibility. But many catchers still use regular nail polish. As one catcher put it: “At first, I just put white on it. I used to use Wite-Out and then I’d have to take it off after games and it was messy. I just decided to put on a color that kind of pops out.” In this case, the color choice is purely functional, not fashion.
Self-Expression and Personal Branding
For many high-profile athletes, black nails are simply a form of self-expression, no different from tattoos or custom cleats. Sprinter Noah Lyles has turned his nails into a canvas that changes with every competition. At the 2024 Paris Olympics opening ceremony, his nails spelled out “ICON” in blue on white. For the men’s 100-meter final, he wore stars, crosses, and lightning bolts in red, white, and blue. At other meets he’s gone with striking red and black combinations or silver crosses on white polish.
Chicago Bears quarterback Caleb Williams unveils a new nail design for every game, sometimes incorporating messages or themes tied to causes he supports. Part of his motivation is personal: Williams uses his nails to promote his mother’s business, a gesture fans have largely embraced. “He’s proving to his fans that he does not need a shirt, or any other kind of merchandise to advertise her business,” one supporter noted. Williams has also been known to spell out messages to opponents across his fingers, treating his nails like a billboard that cameras catch every time he throws a pass.
Former NFL receiver Kenny Stills put it plainly when a teammate was questioned about his nails: “It’s color on nails. That’s like someone asking what’s up with all these dudes getting tattoos. Self expression.”
A Tradition Older Than You’d Think
Male athletes painting their nails isn’t as new as it looks. In ancient Babylon, male warriors painted their nails with ground minerals as a pre-battle ritual meant to intimidate enemies. In modern sports, Dennis Rodman broke the barrier in the 1990s, wearing nail polish alongside dyed hair and unconventional outfits both on and off the basketball court. “Painting your nails doesn’t make u gay,” Rodman tweeted in 2013. “I love to paint my nails. Nothing wrong with that. Be you. Always.”
What’s changed is scale. A generation of Black male athletes in particular has normalized nail art as part of their pregame look, pushing past gender norms that once made any grooming beyond a haircut feel off-limits in professional sports. Rodman was treated as an outlier in his era. Today, painted nails barely draw a second glance in an NFL locker room.
Raising Awareness for Causes
Some athletes paint a single nail as part of the Polished Man Campaign, a global initiative to end violence against children. The campaign asks participants to paint one fingernail to spark conversation about a stark statistic: one in five children worldwide experience physical or sexual violence before the age of 18, and one child dies every five minutes as a result of violence globally. The painted nail is designed as a conversation starter, and athletes with large platforms can turn a simple manicure into millions of impressions for the cause. The campaign runs every October, which is when you’ll see the most single-nail posts from athletes on social media.
Why Black Specifically
Black is the most popular color for a few overlapping reasons. It’s the easiest dark shade to match with any uniform or outfit. It carries a toughness associated with combat sports, where the trend gained early traction among MMA fighters. It hides chips and wear better than lighter colors, which matters when you’re playing a three-hour game or a full day of competition. And for athletes who want to make a statement without drawing maximum attention, black reads as confident rather than flashy. It’s the entry point: bold enough to notice, subtle enough to feel comfortable for someone trying nail polish for the first time.