With summer's hottest temps quickly approaching, you may be wondering what your summer uniform should look like on busy, off-duty days when the heat is sweltering.

Take a page out of a celeb's book - like Kaia Geber, Hailey Bieber, and Kendall Jenner. They love relying on coordinating activewear sets for simple, polished styling — making matching activewear sets the dependable, no-brainer summer trend we can't wait to try. 

• Activewear Already Selling Out: NikeSkims Matte Ditsy Floral Set
• Fashionable Two-Piece Tennis Set: FP Movement Advantage Set
• Outfit for the Gym to Brunch: PINK Relay™ Full-Zip Jacket & Circle Skort

Due to form, function and comfort, athletic gear is a clever uniform for active summer days — the key is finding activewear that's both presentable and comfortable enough for daily wear. For that, celebs love relying on coordinating sets, like a top or sports bra with matching bottoms, for simple styling when on the go. Lucky for shoppers, leading brands like Alo, Free People, Skims and Nike have all thrown their hat into the ring with trendy new-season co-ord sets worth shopping (and wearing) ASAP. 

Whether you're hitting a workout or just running errands, you'll be happy to do it in Lululemon's elongated scuba shorts due to the comfy tie waist and convenient hand pockets. Pair the go-anywhere shorts with a white crop top to compelte the look. 

Shades of espresso have been increasingly popular this year, sport the trendy neutral shade with a classic Alo shorts and sports bra set that'll never expire. 

New from NikeSKIMS: every piece in this "ditsy floral" print is already selling out — don't miss the matching headband too. 

Cue the pickleball and tennis matches! Be the best-dressed on the court in this lightweight, breathable two-piece set: available in several color-ways, the skort features built-in shorts while the crop top includes padded cups. 

The layered look is proving to be quite popular this season, and this Old Navy 2-in-1 sports bra has the added benefit of extra support. 

Polka-dots are the 'it' print of the year and are still going strong into summer, this red iteration screams "I'm ready for summer fun!"

Celebs like Kaia Gerber love Vuori for its practical and comfortable clothing, and this new-season shade of sea foam blue (in two of the brand's bestselling styles) is just begging for a beach day. 

Athleta is a staple in activewear due to its stellar savings and trendy designs. Case in point, this tie-dye set features PowerMesh fabric for breathability and water-repellant compressive shorts. 

This classic Adidas set can take you anywhere this summer; like from early morning pilates, to mid-day errands, to an afternoon stroll with the family, for example. 

Gingham for summer is always a good idea, so we're obsessed with this matching set from Beyond Yoga. The racerback tank has a shelf bra for medium support, and pairs perfectly with biker shorts that won't ride down during your workouts.

Who said gym clothes can't be cute and fun? This new zebra print from PINK is the ultimate summer itteration of the animal print trend, available in a slew of styles, but our favorite is this playful zip-up and skort set. 

Comfort is key with Reebok's oversized tee shirt, providing a relaxed fit, and longline biker shorts, making this comfy set ready for anything summer can throw your way. 

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