Sincerely Jules for Bandier Collection — Official
Our collaboration with Julie Sariñana brings West Coast ease to studio-ready performance. These high-waist leggings feature a compressive four-way stretch fabric that moves with you through every pose and sprint. The mid-rise silhouette sits comfortably at the natural waist, while flatlock seams eliminate chafing during high-output training.






Julie Sariñana launched Sincerely Jules as a style diary in 2009, documenting her approach to effortless California dressing. When we began conversations about a collaboration, she made one thing clear: activewear needed to work as hard off the mat as on it.


Fabric Technology and Performance
We engineered the collection’s primary fabric — a nylon-spandex blend with four-way stretch — specifically for this collaboration. The material offers 25% stretch in both directions while maintaining compression that supports muscle during movement.
Moisture-wicking properties pull sweat away from skin and spread it across the fabric surface for faster evaporation. We tested the blend through 50 wash cycles to ensure color retention and shape stability, then added a brushed finish for a hand feel that reads as premium rather than synthetic.

Sizing and Fit Guidance
Julie wanted the collection to fit a range of body types without requiring excessive size options. We achieved this through strategic fabric choice and grading.
The leggings run true to size with moderate compression — if you prefer a looser fit or fall between sizes, we recommend sizing up. The high-rise waistband measures 3.5 inches across all sizes, offering coverage without restricting breathing or bending.
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Questions About the Sincerely Jules Collection
This collaboration reflects Julie Sariñana’s design aesthetic — minimalist, West Coast-inspired, and built for life beyond the studio. We worked with Julie to refine proportions, select neutral colorways, and prioritize soft-hand fabrics that feel premium. The collection includes exclusive silhouettes and fits not available in our core line, with details like extended inseams, raw-edge hems, and oversized outerwear cuts.
The leggings run true to size with moderate compression. If you prefer a looser fit or typically fall between sizes, we recommend sizing up. The high-rise waistband measures 3.5 inches and sits at the natural waist across all sizes. Refer to the size chart on the product page for your specific waist and hip measurements, or reach out to our styling team for personalized guidance.
The sports bra offers medium support, making it ideal for studio classes, yoga, Pilates, barre, and moderate-intensity runs. For high-impact activities like HIIT or CrossFit, you may prefer additional support from one of our high-impact styles. The bra features adjustable straps and a wide elastic underband to help you customize the fit.
The hoodie is designed with an intentionally oversized, relaxed fit as part of Julie’s aesthetic. Many customers who prefer a closer fit size down, but the roomy silhouette is meant to layer over sports bras and tanks. Check the size chart for chest and length measurements to determine which size best matches your preferred fit.
Always wash items in cold water on a gentle cycle and avoid fabric softener, which can coat fibers and reduce moisture-wicking properties. Tumble dry on low heat or hang to dry — high heat damages spandex and can cause shrinkage. Adding a half-cup of white vinegar to the rinse cycle helps eliminate odors and restore breathability. With proper care, these pieces will maintain their shape and performance through hundreds of wears.
Yes, the neutral color palette — black, white, grey, dusty rose, and sage — coordinates seamlessly with our core activewear collections. The minimal branding and clean lines make it easy to mix these pieces with other tops, bottoms, and outerwear in your wardrobe.
The joggers are made from the same moisture-wicking, four-way stretch fabric as the leggings, so they perform well during warm-ups, stretching, and light training. The tapered leg and secure pockets also make them ideal for travel, errands, and off-duty days. They bridge the gap between technical activewear and everyday comfort.






