Period Solutions for Competitive Swimmers
swimming because of their period
Every unnecessary peel-off counts.
UnderSwim™ OG
Invisible.
Not invisible
coverage.
UnderSwim™ OG fits under any swimwear — including tech suits — without adding bulk, changing the silhouette, or showing through the suit.
The sealed lining sits between the absorbent core and the water, so flow gets locked in while chlorine and water stay out. No tampons. No pad-and-pray. No emergency suit peel.
Watch how the layers work.
Built for the
starting block.
Holds up to 3–4 pads
Higher absorbency core for longer cover during heats, finals, and long meet days.
Sealed lining
A waterproof barrier under the absorbent core locks flow in. Chlorine and water stay out.
Water and chlorine resistant
Protective coating holds up through repeated pool sessions without degrading.
Seamless design
No visible lines or bulk under tight race suits. Hides cleanly under any swimwear.
USA Swimming compliant
Meets USA Swimming guidelines. Endorsed by Swimming Australia.
Less changing. More racing.
Fewer suit peel-offs during a meet. More time focused on the race.
Race day.
Period day.
Same day.
When a tech suit takes ten minutes minimum to get on, reliable period protection underneath matters. Here's how to set up for meet day.
Put on UnderSwim™ OG first
Step into it like regular underwear. It sits flat against the body, ready for the suit to go over the top.
Pull on your tech suit
No adjustments needed. The seamless cut sits flush — nothing to see and nothing to feel through the suit.
Race. Repeat.
Multiple heats in one day? UnderSwim™ OG holds up to 3–4 pads worth of flow — most swimmers can go the full meet without a change.
What can you wear under a
tech suit on your period?
Most period management options aren't built for competitive swimming. Tampons can absorb pool water and reach capacity faster. Period swimwear with a built-in gusset adds bulk that shows through a tech suit. Pads don't work in water.
UnderSwim™ OG is cut and constructed specifically to be worn as a second layer under swimwear. The absorbent core manages flow; the sealed lining stops water entry. Slim enough for tech suits. Reliable enough for full meet days.
Can you wear a tampon with a tech suit?
You can, but pool water absorption can shorten how long a tampon lasts. Some swimmers use UnderSwim™ OG as a backup, others use it instead.
Will it show through a tight race suit?
No. The seamless design sits flat against the body. It's built to disappear under close-fitting swimwear.
What about multi-event meet days?
With up to 3–4 pads of absorbency, most swimmers can go a full meet day without needing to change. One less thing to manage between heats.
Is it allowed in competition?
Yes. UnderSwim™ OG complies with USA Swimming guidelines and is endorsed by Swimming Australia. Swim England guidelines are also met.
How does the waterproofing work?
A sealed lining sits between the absorbent core and the outside of the garment. Flow is absorbed into the core; the sealed barrier stops pool water getting back in.
How to Wash
Period Swim Undies
Rinse immediately
Right after the pool, rinse in cold water. This removes chlorine and salt water before they break down the waterproof coating.
Cold machine wash
Wash on a cold, delicate cycle. Keep them out of the dryer — heat damages the sealed lining over time.
Hang to dry
Air dry flat or on a hanger away from direct heat. Same care process as regular period underwear.
Less changing. More racing.
Shop UnderSwim™ OGCompliant with swimming authority guidelines
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