Finding the right underwear shouldn't be complicated. But if you've ever dealt with chafing on a run, underwear that rides up during a workout, or pairs that lose their shape after a few months, you know how much your first layer matters.
At Paradis Sport, we've spent years designing performance underwear alongside elite female athletes. Along the way, we've answered hundreds of questions about fabric, fit, washing, sustainability, and what actually makes great underwear.
Here's everything we've learned.
Question: How often should you replace your underwear?
Answer: There is no one-size-fits-all approach to buying new or getting rid of old underwear. However, there are signs that typically signal the need for a new pair (or a few…).
For example, if your underwear is starting to sag, lose elasticity, the fabric is thinning or you notice discoloration in the fabric (from sweat, etc.), then it’s likely time to bid farewell.
This could happen anywhere from 6-months to a year after you’ve purchased them, and varies per person depending on how often you wear them and how you wash/dry them.
At Paradis Sport, a core aspect of our design process is a focus on the lifecycles, and specifically, longevity of our products. With this, we have created each of our underwear to last as long as possible, thereby reducing waste.
In fact, our durable and high quality products are built to last hundreds of wash cycles with proper care.
Also, we offer bundles of our underwear so that you can stock up on your favorites! The more you have, generally the longer they will last :)
Question: How many pairs of underwear do you actually need?
Answer: Every woman’s lifestyle is different. In our view, the ideal number of underwear you should have depends on factors such as your exercise regularity, work and travel schedule, hobbies, and every day activities.
According to Healthline, most people wear one pair of underwear per day and then place it in their laundry bin. However, you may prefer to change your underwear more than once a day, especially after exercise. Healthline also notes that changing underwear daily (and even more frequently) is good hygiene practice.1
It’s also worth accounting for life’s interruptions. Maybe your kid’s weekend tournament ran longer than expected. Maybe a work trip gets extended overnight. Maybe you’ve been traveling, have friends or family staying over, or you’re simply navigating a busy week. Whatever the reason, having a lasting supply of underwear means one less thing to worry about when you're busy or plans change unexpectedly.
With that, we would recommend having a two-to-three-week supply of underwear on hand as it seems to be the sweet spot. That means about 14-25 pairs, which should give you enough flexibility to not run out between laundry days, while traveling, or dealing with whatever life is throwing at you.
Let’s be honest, doing laundry is not always the most enjoyable. The more pairs of underwear you have, the less likely you’ll run out in between loads! Having a few extra pairs also helps you to avoid over-washing some of your favorites, which can then cause the elastic and fabric to wear quicker.
Question: What is the best underwear fabric to work out in?
Answer: It depends on the workout, but there are a few key qualities that we would suggest you look for to move freely and be as comfortable as possible so you can focus on your workout or reaching your goals during that race.
So, what should you look for?
First, the fabric should prioritize moisture-wicking, breathability and should ideally stay in place. Fabrics such as nylon and spandex blends do this well, whereas 100% cotton is typically not ideal as it absorbs moisture too easily to really allow for the most comfortable and long-lasting workout.
If you’re looking for a natural fiber material, a quick-drying fabric such as modal is also a strong performer. Modal is made from harvested beech tree pulp and is highly breathable and naturally thermoregulating.
We also believe that your workout underwear should not chafe or ride up (wedgies..ugh). According to a recent study, a resounding 92% of marathon runners reported chafing during a race.2
We've spent a significant amount of time researching and testing our underwear with high-performing athletes, and the results have truly paid off. One of our best sellers is our seamless line - made from BPA-free and PFAS-free super-soft, micro denier recycled nylon and spandex yarns - which is designed to ensure maximum comfort and durability. This not only provides a luxurious feeling against your skin and four-way stretch, but the fabric also wicks away moisture and dries quickly, keeping you cool and dry during any activity. We would recommend our seamless line for running, and it also performs well at the gym during training, lifting, or waiting in line for that expensive-but-worth-it post-workout smoothie.
Our natural fiber line - another best seller - is made with Superfine™ micro-modal fabric, one of the finest knitted fabrics in the world. It is derived from sustainably harvested beech tree pulp and offers exceptional softness and breathability. This collection is also great for running and is so comfortable that many women wear them for everyday and all-day wear.
Our experts put together this handy product comparison chart so that you can easily see and compare all of our underwear lines depending on your type of activity (as well as other helpful factors like feel/comfort and fabric performance). Take a look for yourself!
Question: What is the best way to wash and dry your underwear?
Answer: Given the very nature of this first layer, underwear rubs up against some of the most sensitive areas of your body for long periods of time. Because of this, it is very important to think about how we wash and dry it, even if the process feels unnecessary or time consuming.
In general, it is recommended to use gentle and hypoallergenic detergent to wash your underwear. Detergents that contain harsh chemicals could be dangerous as they can leak out of the fabric and cause itching, irritation, and even allergic reactions.3
We would also recommend trying to stay away from fabric softeners as these products can weaken elasticity in the underwear and also create irritation in sensitive areas.
A rule of thumb for washing your underwear is to use cold water and a delicate wash cycle. When possible, use a mesh laundry bag to avoid your underwear getting caught with other articles of clothing, especially ones with zippers, clips or buttons.
We also HIGHLY recommend air drying your underwear. Yes, it takes more time, but it tremendously helps keep the elasticity of your underwear intact for as long as possible.
Question: What should I look for when buying underwear if I care about sustainability?
Answer: According to the United Nations, sustainability is the practice of “meeting the needs of the present without compromising the ability of future generations to meet their own needs.”4
We get it. There has been a lot of talk about sustainability and what that really means. From an acceleration into a focus on sustainability following the Covid pandemic to more recent fears about greenwashing and misinformation, we believe that there are key differences between the noise and what a brand’s focus on sustainability really means.
At Paradis Sport, sustainability is at our core. It’s our guiding principle that ties all that we do together. From the very beginning, we have focused on the durability and circularity of our products, meaning, how can we reduce waste as much as possible from the initial inputs to the end-use of our underwear.
With that in mind, our seamless underwear construction reduces manufacturing waste, and we ship our products in approximately sized, recycled and recyclable packaging. We also offer a way to recycle not only our products but your old underwear by partnering with Green Tree Recycling so that these garments don't end up in a landfill.5
Along with circularity, we also integrate a focus on sustainability into our fabrics. For example, our natural fiber line is made with micro-modal, a fabric made from sustainably harvested beech trees. Micro-modal fabrics are more environmentally responsible, sourced from a natural fiber (wood) making them better for you, and the planet.
Finally, we are proud members of the 1% for the planet initiative. Since 2021, through our Give Back Partnership Program, we've donated 1% of profits to CREA Mont-Blanc, a Chamonix-based research center that studies the impacts of climate change on alpine ecosystems. In June 2026, we were proud to partner with and donate our 1% of profits to Little Bellas, an organization dedicated to empowering young females through mentorship on bikes.
We are constantly looking for ways to hone our focus on sustainability even further, and are excited to share the progress we make about our commitment to the planet and future generations with you!
Question: What can I do with my old underwear?
Answer: An age old question, and we have a great recommendation. Recycle them!
Like many things, while it may be tempting to toss old underwear in the trash, luckily there are more sustainable options available.
At Paradis Sport, we are committed to reducing textile waste and keeping our underwear out of landfills. That’s why we are partnered with Green Tree Recycling, an organization that gives old textiles a new life by shredding and repurposing the material as industrial building insulation or other useful materials.
If your underwear has reached the end of its life, all you have to do is box up your old pairs and send them to a Green Tree Recycling drop-off location. It’s that easy!
Question: What do you wish more women knew before buying underwear?
Answer: The importance of your base layer clothing for your health can be overlooked. Understandably, many women look to purchase cheap underwear made from low quality products that you might be able to buy in bulk. Or many, frustrated by a lack of comfortable or seamless options, choose to go commando during workouts and not wear any underwear at all.
However, as we wrote in our blog post, there has been growing attention to an alarming trend - the use and discovery of harmful, hormone disrupting chemicals in activewear. Studies have shown that these chemicals (such as BPAs and/or PFAS), can be detrimental to our health in a variety of terrifying ways.
As more research continues to help us better understand the links between these chemicals and our health, there are easy steps you can take to protect yourself against the risks. One of them is to buy products that are free of harmful BPA and PFAS chemicals such as Paradis Sport’s underwear!
We are proud that the fabrics we use and manufacturers who make our products are OEKO-TEX® STANDARD 100 and bluesign® certified, which means that every component—from the threads to the final fabric—meets stringent testing criteria.6 This guarantees our products are chemical-free, responsibly crafted, and safe for your everyday wear.
Endnotes:
1. Healthline, “8 Underwear Rules to Live by for a Healthy Vagina”, Last medically reviewed on August 16, 2024.
2. Runner’s World, “A massive 92% of marathon runners experience chafing – here’s how to prevent it from ruining your race”, April 2026.
3. Healthline, “8 Underwear Rules to Live by for a Healthy Vagina”, Last medically reviewed on August 16, 2024.
4. United Nations, “Sustainability”, accessed in May 2026.
5. Green Tree shreds and repurposes the material as industrial building insulation.
6. For more information, please see the respective websites for OEKO-TEX, and bluesign.
