Why are there such strict rules around ski jumping suits?

There’s been chaos in the mixed team ski jumping event at the Winter Olympics, with four of the most competitive countries – Germany, Japan, Austria and Norway – disqualified because some of their athletes failed to meet ski suit regulations.

So why are these regulations so strict, and how is it possible that five athletes, all with a good chance at gold, could fail to meet the dress standards?

In many cases, it comes down to weight. Lighter athletes can jump further.

“The lighter you are, the more the lift force is going to hold you up in the air, basically,” explains Kevin Netto, associate professor in biomechanics at Curtin University’s School of Allied Health.

“The ski jumpers try to form an aerofoil sort of a shape, like an aeroplane wing. What they’re trying to do is optimise drag, but also get lift.”

Being lighter in weight carries another advantage: it can make your suit more parachute-like.

“There’s a real double prong to it,” says Netto.

“The lighter you are, potentially the smaller you are as well. And the smaller you are means that the suit becomes a little bit loose in some areas. When the suit becomes loose in some areas, it creates more of a surface area that you can apply lift to.”

This is why there are very strict requirements around both how thick and tight a suit has to be, and ski length – which is linked to individual body mass index.

But even though these regulations have been introduced to protect athletes’ health, it’s still in a ski jumper’s best interest to be as light as legally possible. Unlike in longer distance events, there’s little to be gained from eating a meal or being well hydrated beforehand, for instance – “You’re asking a lot of your body but you’re asking it in very short bursts,” says Netto.

Some of the athletes disqualified yesterday say they were wearing suits that had passed muster just a few days prior in the individual event, meaning that either the athletes had lost weight, or the Olympic officials’ methods for checking the suits had changed.

Is it possible for enough weight to have been lost over a few days to disqualify an athlete in an event? In short, yes. Canadian Alexandria Loutitt, for instance, had been disqualified from the individual event on Saturday for weighing in 300g too light – something that drinking a large glass of water would remedy. And, indeed, she did qualify for last night’s event, and won a surprise bronze medal with her team.

There’s no evidence that any athlete was deliberately losing weight, and at least one is saying that the Olympic officials changed their methods of measuring suits.

But either way – ski jumping is a sport that operates on very tight margins. A few grams can make the difference between gold, silver, and not competing at all.