Techsuits: How material science breaks world records

Science has long played a role in sports, and swimming is no exception. In competitive
swimming, a single millisecond can be the difference between winning gold or missing the
podium entirely. While training, technique, nutrition, and talent remain essential, a surprising
game changer that people don’t often think about is the actual swimsuit.
Those long, strange-looking swimsuits that you see on TV, also known as tech suits or fastskins,
are high-performance swimsuits engineered using physics and advanced materials science.
Designed specifically for competitive swimming, they reduce drag, compress muscles, and
optimize body position in the water. They were so effective that at the 2008 Beijing Olympics,
over 90% of swimming records at the time were broken with just one model of suit.
The technology was so dominant that regulations had to step in. One swimsuit had changed
everything, pushing the limits of science and challenging the very integrity of the sport.

Speedo LZR fastkin speedo.com

But how do they actually work?
Water is around 830 times denser than air, so as you can imagine, drag is a swimmer’s biggest
enemy. That’s why tech suits are built to fight this resistance using smart design and powerful
materials.
The fabric is typically made of a very tight blend of nylon and elastane, sometimes even
reinforced with carbon fiber. This combination creates a lightweight but highly compressive
layer that wraps around strategic muscle groups, improving posture and streamlining the
swimmer’s body. Not only that, by compressing the muscles, it reduces vibration and can even
delay fatigue by limiting lactic acid buildup. They are incredibly hard to put on! Much harder
than you’d expect , tiny and non-stretchy, it often takes up to 25 minutes (and help from
someone else) to get them on. Some suits feature an outer coating of silver or similar material
to make them more hydrophobic, so they repel water rather than absorb it. That means less
weight and less drag.
To take it even further, the seams aren’t stitched like normal clothes. They’re ultrasonically
bonded, so there are no bumps messing up the water flow. As you can see, every little detail
matters and is taken into account when making these suits.
As an interesting fact, some designs are even inspired by nature, such as shark skin, with
microscopic structures called denticles that help guide water flow and reduce turbulence. Tech
suits mimic this using microtextures and surface engineering, applying ideas straight from fluid
dynamics and aerospace research.
However, the most controversial innovation was the use of polyurethane panels, a lightweight,
naturally water-repellent, and slightly buoyant rubber-like material (you’ve probably seen it as
the foam inside sofa cushions or insulation panels in walls). These panels trapped pockets of
air, improving the swimmer’s body position by helping with buoyancy and further reducing
resistance in the water.
The suit that caused more controversy was the Speedo LZR Racer 2008 suit. Designed in
collaboration with NASA, it reduced passive drag by up to 24% compared to a traditional
swimsuit. The LZR Racer helped break most of the world records in just one season. So of
course, many argued that this was very unfair, as it was no longer just about the swimmer but
about the suit.
In response to the controversy, FINA (Swimming International Federation) introduced new
regulations in 2010. From then on, swimsuits could no longer cover the neck or go past the
shoulders or knees. They had to be made from textile fabrics, not polyurethane, and limits
were also set on thickness and buoyancy.
As a competitive swimmer and materials science student, this is a very interesting subject to
me and I really wanted to share. I’m sure you didn’t think there was so much behind a sport
that seems to involve barely any equipment! Or at least not equipment that could make such a
difference. Research is still ongoing but focusing more on the goggles and cap (as there are not
many regulations on that yet). It makes you wonder: how fast can humans really swim, and
how much of that will be thanks to technology? Anyway, I hope you enjoyed this post and
learned something new.
Thanks for reading!

References:
NASA: Space-Age Swimsuit Reduces Drag, Breaks Records
https://www.nasa.gov/technology/tech-transfer-spinoffs/tech-today-space-age-swimsuit
reduces-drag-breaks-records/
Engineering.com: The Technology Behind Speedo’s High-Tech Swimsuits That Challenged the
Olympics
https://www.engineering.com/story/the-technology-behind-speedos-high-tech-swimsuits
that-challenged-the-olympics
Wikipedia: High-Technology Swimwear
https://en.wikipedia.org/wiki/High-technology_swimwear
XtremeSwim Blog: How Swimming Tech Suits Work
https://xtremeswim.com/blogs/swim-blog/how-swimming-tech-suits-work