From cryotherapy chambers and kinesiology tape to supplements and ‘oxygen in a can’, elite football is increasingly turning to treatments and products with little scientific evidence behind them, warns performance director Dr Claire-Marie Roberts, in a Guardian article.

When Dr Claire-Marie Roberts was working at Coventry City, she received a rather unusual sales call.

The caller wanted to know if she knew how much oxygen was in the atmosphere.

As the club’s performance director, Roberts was used to receiving pitches for the latest devices, supplements and technologies promising to unlock hidden performance gains. At one point, she says, she could receive as many as 50 LinkedIn messages a week from people selling products that claimed to offer miraculous results.

“It is only 21%,” the caller told her.

Then came the pitch.

“So what we’ve done is put oxygen in a can and we think you might want to use it.”

“Right … oxygen in a can,” Roberts recalls, laughing.

She did not buy it.

For Roberts, however, the episode represents a much bigger problem in elite football: the growing influence of pseudoscience.

Roberts has spent decades working in elite sport and professional football, including nine years at the Premier League and two at Coventry City. She played a key role in the club’s promotion as Championship champions before joining Formula One team McLaren as director of human performance this summer.

From her experience, she believes football is increasingly vulnerable to products and practices that promise quick fixes without having the evidence to back them up.

“It’s the science-practice gap, which is widening in my experience,” Roberts says. “I think it’s getting much worse. There’s so much sparkly marketing behind all these things. It’s bordering on exploitation.”

The appeal is obvious. Professional footballers operate in an environment where tiny advantages can have enormous financial and competitive consequences. Players are constantly searching for ways to train harder, recover faster and extend their careers.

But that desire for an edge can also make them easy targets.

“They’re taking a population that is very susceptible to: ‘How can I hack my performance advantage? How can I shortcut my preparation and recovery?’ Which I don’t think is a great starting point.”

The cryotherapy craze

One of Roberts’ biggest concerns is whole-body cryotherapy, a treatment now commonplace at elite training grounds.

When a cryotherapy chamber is unavailable, ice baths often provide the alternative. Players themselves appear to embrace the practice. Harry Kane was photographed standing in a wheelie bin filled with ice after a Bayern Munich match at last year’s Club World Cup.

But Roberts questions how much clubs actually know about why they are using it.

“Most clubs have got cryotherapy chambers – most people cannot articulate to you why they use them, because there’s no evidence for them apart from a very slim piece of work that says it might help prevent dementia,” she says.

“There’s very sketchy evidence on cryotherapy.”

There may even be situations where the treatment works against the very adaptation athletes are trying to achieve.

“There’s a recent suggestion that cryotherapy might blunt muscular adaptation,” Roberts says.

Her argument is simple: clubs should first ask what problem a treatment is supposed to solve.

“If you’re using it for recovery, sleep and nutrition are your best recovery modalities. No amount of putting anybody in a whole-body cryotherapy chamber is going to help them recover more if those two things aren’t taken care of.”

The supplement shortcut

The same mentality, Roberts argues, has seeped into footballers’ diets.

The global supplement industry is worth billions, with professional sport representing one of its most lucrative markets. But Roberts says supplementation should begin with an identified need, rather than the belief that more pills automatically mean better performance.

Vitamin D, for example, can be a legitimate concern for people living in northern parts of the world because of limited sunlight exposure. Other supplementation may also be appropriate where a genuine dietary deficiency exists.

But the basic principle should remain the same.

“You’ve got people popping pills not really asking what they’re for. It should always be needs-based,” she says.

“If you don’t eat fish and fish oil is important to you, you might supplement it. It should all be based on need.”

For Roberts, no supplement can compensate for poor fundamentals.

“Your athletic performance and recovery is based on sleep quality and nutritional quality and amounts. No amount of supplementation will improve a bad diet, but people think it will.”

The same problem applies to training and recovery.

“We don’t do enough of the basics and think we can shortcut and hack everything.”

When big clubs create false confidence

Roberts says she used an evidence-based approach while supporting Frank Lampard’s squad and believes football can sometimes copy practices simply because they are used by successful or wealthy clubs.

That can create what she describes as a “misappropriation of confidence”.

“Because England or Manchester City or Chelsea who have all the resources under the sun have got this, there’s a misappropriation of confidence and understanding of the scientific basis or evidence,” she says.

“It’s powerful in driving behaviour, but it’s driving the wrong behaviour.”

In other words, a treatment does not become scientifically credible simply because a major club can afford it.

Roberts, a former swimmer who missed the 1996 Atlanta Olympics through injury, believes football may be particularly vulnerable to this phenomenon.

“Football is more susceptible to it than any other sport I’ve experienced first-hand,” she says. “I think because the stakes are higher.”

What about kinesiology tape?

Kinesiology tape, commonly known as k-tape, is another familiar sight in professional football.

Players including Cristiano Ronaldo, Gareth Bale and David Beckham have all been seen wearing strips of it on various parts of their bodies.

Roberts is unconvinced.

“There’s no evidence kinesiology tape has any impact on injury prevention or performance-related outcomes,” she says.

She acknowledges that it may provide athletes with a feeling of support or increased awareness of a particular area.

“It gives you a bit of proprioception – maybe you feel like someone has done something – but in any environment I’ve worked in you’d never see anyone wearing k-tape. It’s a big white elephant.”

That does not mean all forms of strapping are useless.

If an athlete has suffered a shoulder dislocation, for example, external strapping can provide some support and remind the player of the injury.

“It’s a risk-mitigation strategy. It’s not hugely successful, but you’d do it rather than not do it.”

K-tape, by contrast, is something Roberts considers a placebo.

Football’s resistance to science

The problem, Roberts believes, is not simply the products themselves.

It is the culture around them.

Managers with decades of experience can become attached to routines they have always used. Coaches can adopt a new product because another coach recommends it. Players can follow trends because they see them being used by famous teammates or elite clubs.

Without people capable of questioning the evidence, those practices can become accepted as fact.

Roberts believes football needs to put scientific scrutiny much closer to the centre of decision-making.

“We think we can accelerate to an outcome without putting the hard yards in – the basic things: diet and sleep and the quality of your training,” she says.

Her criticism goes beyond individual treatments.

“Football in general is very anti-intellectual and it has been for a long time. There are a few clubs that do it well, but the majority don’t.”

“The game is definitely anti-science. There’s a reason for that. There isn’t a critical mass of people that are applying critical thought to situations.”

For a sport obsessed with marginal gains, that may be the biggest contradiction of all.