What is the difference between swim trunks and jammers?
Confused about the different types of male swimwear and what they’re for? Look no further. Elise Metcalf unpicks the differences between trunks and jammers to help determine which option is right for you
The term ‘swimming trunks’ is often used synonymously to describe any type of shorts worn by men when swimming. Yet, men’s swimwear is more varied than it might initially appear and can get confusing. Two popular options of male swimming attire include trunks and jammers. While these may look similar, their design, form and function varies.
What are swimming trunks?
Swimming trunks are light-weight shorts that stop at varying distances above the knee. Most are made of nylon and include a mesh lining for quick-drying qualities. They can be identified by their loose, relaxed fit and are typically not used for competitive swimming as they can create drag in the water. The other side of the spectrum are swimming briefs, or ‘budgie smugglers’, which give the least amount of coverage but ample support in the water. They are more likely to be worn for competitive swimming than trunks, as they are close-fitting and have minimal fabric.
What are jammers?
Jammers are knee-length swim shorts that provide more coverage than trunks, but have more freedom of movement due to their stretchy material. They closely resemble lycra cycling shorts, and are popular amongst competitive swimmers for both training and racing. Usually made of nylon and lycra, or spandex material, their form-fitting design helps to reduce drag within the water. They often have some level of built-in compression, helping to support blood circulation and reduce muscle fatigue. If you want the competitive edge, FINA-approved jammers are available, which are made specifically for racing.
Should I wear swim trunks or jammers?
Both trunks and jammers present a good option for amateur and seasoned swimmers. Trunks are typically for less competitive swimming, or can be used as ‘drag shorts’ to increase resistance in the water for a harder workout. Jammers offer more coverage than trunks and provide a competitive option for performance athletes thanks to their close-fitting design and low-friction material; this is why you’ll see most athletes in either briefs or jammers as opposed to trunks. If you’re all about the aero gains, then hydrodynamic swimskins provide a good option for non-wetsuit legal swims, offering 2-3sec per 100m time savings.
Ultimately, there’s a lot of choice and most important is to sport swimwear that you feel comfortable in, whether that’s a neon pair of briefs, sleek compressive jammers, or Hawaiian-print trunks, is up to you!
Still can’t decide? Check out our swim gear page for the latest kit reviews and advice to help you get ready for your next dip in the pool or swim with the fish.
Elise Metcalf is an amateur triathlete with an avid interest in exercise, nutrition and performance.
Top image by Ibrahim Mohamed, from Unsplash
Kate Milsom
Freelance sports journalist 
