For Olympic athletes, how much a difference do their high-performance suits make? Apparently a lot. Since the LZR line of suits was banned following the Beijing Olympics, Speedo has made suits that are essentially less speedy than they were 7 years ago. Nevertheless, companies like Speedo continue to innovate with materials to achieve higher speed and better athlete performance. At Rio 2016, Speedo unveiled 2 new suits, the Fastskin LZR Racer X and Fastskin LZR Racer 2.

In the 2008 Beijing Olympic Games, 23 world record were set by swimmers wearing the polyurethane Speedo LZR racer, a polyurethane suit. By contrast, only two world records were broken by swimmers not wearing polyurethane suits. The suits were subsequently banned for future Olympic competitions.

In 2009, German swimmer Paul Biderman broke two world records at the World Championships while wearing the Arena Water Instict’s X-Glide swimsuit. Like the Speedo LZR racer, this suit covers the swimmer’s legs and upper body with an impermeable polyurethane, which improves buoyancy and reduces drag.

The suits are the result of intensive research and development, with engineers using water tunnels and computational fluid dynamics to model potential drag effects. The efficiency of these suits was however viewed as a way of ‘tech doping’ and new rules have determined since 2009 how much of a swimmer’s body a swimsuit can cover. Furthermore, suits must be mostly made of a permeable material, rather than the slick impermeable polyurethane.

Despite making their LZR suits less efficient, Speedo continues to innovate with the series, and outfitted team from the United States, Australia, China, Spain, Japan and Israel at Rio 206 with two of their new suits: the Fastskin LZR Racer X and Fastskin LZR Racer 2. These suits work by compressing a swimmer’s body to make them more hydrodynamic, and thus faster.

But speed in the water doesn’t equate to speed in the locker room. It apparently takes up to ten minutes for a swimmer to get into a Fastskin suit. The suits were developed based upon data from 330 elite swimmers, to ensure they are comfortable to wear. The idea is that the more comfortable and natural an athletes feels, the better they will perform.

So clearly, materials matter when it comes to top speed. With records broken ever Olympics, a question becomes, how would legends of yesteryear stack up with today’s champions?

The Canadian Broadcasting Corporation recently undertook a simulation to compare world record breaker Paul Bilderman to the legendary Mark Spitz from the 1972 Games in Munich. When all is equal in terms of clothing, who do you think came out on top? Find out the winner here.