This article originally appeared in the November 2015 issue of SELF. For more from the issue, subscribe to SELF and download the digital edition.
Take a cardio dance class with New York City trainer Katherine Greiner and the first thing you notice is her ripped, washboard-flat abs . The second thing: her enviably strong, glossy brown hair. "I definitely work on my hair like I do my body," Greiner says. Nicole Winhoffer, another top trainer in NYC, has a ponytail that's as fierce as the aerial jumps she performs in class. "I treat my body like a temple, and my beauty and hair routines are an extension of that," she says. This connection between wellness and your hair is definitely real—when you eat right, exercise regularly and manage stress levels, your locks look all the better for it.
Of course, genetics play a role, too. You're born with certain hair qualities (thick versus thin, curly versus straight), but beyond that benchmark, you can actually help your strands become stronger and more resilient. It starts with rotating in the latest products—many of which boost endurance deep within the cortex for long-lasting benefits—and recruiting healthy habits into your everyday routine. Here's your three-step plan to crush any signs of weakness (breakage! split ends!) and pump up your hair so it looks as gorgeous as the rest of you.
1. Build Core Strength
Your hair has to fight off many aggressors, including heat from styling tools, chemicals in hair dyes and straightening treatments, environmental stress (sun, wind, salt water) and abrasion from your brush. In other words: daily life. These things can wear out the outer layer of your hair, making it more prone to damage, notes Melissa Piliang, M.D., a dermatologist at the Cleveland Clinic .
How to strike back? By preserving keratin, a key protein that gives hair steel-caliber strength, Dr. Piliang says. Klorane Conditioning Balm With Desert Date ($16) repairs the cortex and cuticle with the wheat protein hydrolysate, the plant equivalent of keratin. Swap it for your usual conditioner, saturating ends to fend off splits. "The molecules in the balm work like glue to bind cells together, so when you bend your hair, it won't break," explains James Kivior, manager of education for Klorane USA.
You can also knock out damage from postworkout showers. "Metal impurities in tap water can cause oxidative damage and weaken the internal structure of the hair fiber over time," says Rolanda J. Wilkerson, Ph.D., a principal scientist for Pantene . Pantene Pro-V Repair & Protect Miracle Repairing Shampoo ($5) and Protecting Conditioner ($5) contain an antioxidant called histidine, which binds to metal deposits and deactivates them. "After the first wash, your hair looks smoother and shinier," Wilkerson says. (And in the company's lab tests, this cleansing duo doubled hair's strength after one use. Impressive.)
Another idea: Lather up less often, "to give your hair a chance to rest and recover," Greiner says. On those off days, try misting your roots with a mattifying sea-salt spray, she says, which helps absorb excess oil and grease.
2. Add Toning Sessions
Hair masks and serums are like the conditioning sessions you do a few times a week to target different body parts. Phyto PhytoKeratine Extreme ($59) is rich in amino acids and sapote butter to make hair resistant to almost anything you throw at it. Keep it on hand if you color or straighten your strands often (for fine hair, leave the mask on for 2 to 3 minutes; for thicker types, let it sit for 10 minutes).
Or consider Winhoffer's DIY trick: She massages nourishing olive oil into her scalp, then covers her head with plastic wrap for 20 minutes. (Like your postrace Mylar blanket, it seals in heat, and in this case, helps the ingredients penetrate.) "I do this two times a month so my hair stays thick and beautiful," she says.
3. Maintain The Results
To keep those Ironwoman-like locks, stick with healthy practices: Go easy on styling tools and limit heat. "Three hundred degrees is the max setting I'd put any tool on," Dr. Piliang says. It also helps to apply a heat-protective spray beforehand. Oribe Imperial Blowout Transformative Styling Crème ($68) contains skin-care-like ingredients and humectants to seal in hydration; it morphs from a cream to an oil to a volumizing powder to solve multiple needs (the CrossFit of stylers!).
When doing your workout ponytail , secure it with no-crease hair ties, recommends Jill Engelsen, a senior stylist at Butterfly Studio Salon in NYC (her pick: L. Erickson Ponytail Holders ). At night, let your hair down. "Don't sleep with it tied up, as it can cause breakage," she says.
Lastly, mitigate damage from those forces you can't control—like the weather. "When the humidity drops in winter, there's less moisture in the air, which can cause dryness and dullness," Dr. Piliang says. Greiner's fix: drinking hydrating green juices and hitting the gym even harder. "Working up a sweat really moisturizes your hair with natural oils," she says. It's all part of a healthy cycle. As Greiner puts it, "Everything you do is connected: healthy mind, healthy body, healthy hair."
Above: To tame flyaways, mist on Nexxus Frizz Defy Hair Spray, $12. Jacket, $165; TorySport.com
Styled by Lindsey Frugier. Hair, Wesley O'Meara for Ag Hair; makeup, Sam Addington for Chanel Les Beiges; model, Britt Bergmeister at Next.
Photo Credit: Jason Merritt / Getty; Christopher Ferguson