Horse sports are a leading cause of traumatic brain injuries. Can they be made safer?

The risks of traumatic brain injuries in American football are well known, but some researchers have found that sports involving horses are also a leading cause.

These injuries can be fatal and usually occur during falls of either the rider or both the horse and the rider. Last month, British event rider Georgie Campbell died after a fall while competing in the Bicton International Horse Trials in Devon, England. Her death has renewed focus on the perennial issue of safety in the sport.

Jonathan Holling, who holds top safety roles in the U.S. and internationally, told NPR's A Martínez that "there's an element of risk" around horses, whether it's for top competitive sports or simply pleasure riding.

"There's probably no greater risk in equestrian sport that something's going to go wrong as there is in any other sport," added Holling, the national safety officer for the U.S. to the International Equestrian Federation — the governing body for horse sports worldwide.

"It's just that when it does, you don't have a 300-pound lineman that's going to fall on you; you have a 1,200-pound horse... so the consequence can be really great."

Holling competes in three-day eventing, an Olympic sport that combines three disciplines: dressage, showjumping (over fences with wooden or plastic rails that fall when hit) and cross-country.

In that last phase, horse and rider combinations gallop across a hilly field, jumping over solid fences and into water over banks and ditches while trying to make it within a tight time allowed. "It's pretty high adrenaline and really exciting," said Holling.

But with that excitement comes risk.

It's a risk Marie Vonderheyden knows all too well. In 2015, the French-American rider's horse spooked during training. She suffered a severe traumatic brain injury from the fall, spent two months in a coma and lost much of her memory. Over the next two years, Vonderheyden learned how to walk, speak and perform basic tasks again, ultimately returning to riding for equine-assisted therapy.

She began competing in para-dressage in 2019 and is now training for the 2024 Paralympics. As with other equestrian disciplines, the para-dressage competition will take place outside Paris at the Château de Versailles that King Louis XIV once called home.

"There's only so much you can do if you're riding a horse and something goes terribly wrong and you whack your head," said Holling, who chairs the U.S. Equestrian Federation's Eventing Sport Committee and serves on the U.S. Eventing Association's Cross-Country Safety Subcommittee. "It all happens so quickly. You're talking split seconds."

So sports regulators focus on how to minimize the risks of such accidents happening in the first place.

Holling has broken both of his legs and both of his arms around horses. He points to the importance of fitness, competing at skill level and efforts to better train riders on safety. Keli and Danny Warrington, a former gymnast and a jockey turned three-day event rider, respectively, run one such program called Landsafe.

And horses get checked regularly by veterinarians to address any potential chronic issues and reduce the potential for injuries.

Innovative safety features have also helped. "We tried pretty hard in the sport... to mitigate that risk (of falling) and to try to encourage, especially from the private sector companies to come up with better safety advice, better helmets, better vests," said Holling.

Solid fences are safer today thanks to safety features like frangible pins and MIM clips that make a fence fall or collapse when hit. Since 2012, rotational falls — somersaults before landing on its back — have dropped by 55.5%, according to FEI figures for eventing.

But it's still not fool-proof.

"You want to make sure you've got all the right safety equipment on, you've done all the right preparation work, you have your horse fit, that you've taught them all of the potential questions that are going to be asked on that cross-country course so that you can have the safest, best round possible," Holling said.

Just days after Campbell's death in the UK, British Eventing announced a new research project that will have riders wear sensors to determine any associations between speed, performance and faults or falls in cross-country. The association stressed that the project was formalized in April — weeks before Campbell's deadly fall.

The broadcast version of this story was produced by Nina Kravinsky. The digital version was edited by Obed Manuel.