World Cup 2026: Why the Team That Manages Fatigue Best May Lift the Trophy

By Dr Neil Clarke, Associate Professor of Sports Science, Birmingham City University

When the World Cup kicks off this summer, billions of fans will focus on the usual questions.

Is this finally England's year?

Can Argentina retain their crown?

Will France's incredible depth prove decisive?

But according to sports scientist Dr Neil Clarke, one of the biggest factors influencing who lifts the trophy may have nothing to do with tactics, talent or star players.

It may come down to fatigue.

"The challenge for players at this World Cup is unique," says Clarke. "Normally players have a pre-season where they can build fitness and prepare for a campaign. Here, they're coming straight off the back of a long domestic season and going into one of the most physically demanding tournaments football has ever seen."

With the competition expanded to 48 teams and matches spread across vast distances in the United States, Canada and Mexico, players face a perfect storm of challenges. Long-haul travel, extreme temperatures, altitude, disrupted sleep patterns and relentless match schedules will all place additional stress on athletes who have already spent ten months pushing their bodies to the limit.

"The challenge isn't improving fitness at this stage," Clarke explains. "The challenge is managing fatigue."

That may sound obvious, but modern football has changed dramatically over the past two decades.

While total distances covered have increased only modestly, the intensity of the game has risen significantly. Today's elite players spend less time walking and jogging and far more time accelerating, decelerating, sprinting, tackling and changing direction at high speed.

"It's the high-intensity work that's really demanding," says Clarke. "The repeated sprinting, the accelerations and decelerations, the explosive actions. That's what takes the biggest toll on players."

The consequence is that fatigue often shows itself in subtle ways before fans notice it.

Players may still be able to cover ground.

They may still appear active.

But the explosive actions that decide matches begin to decline.

The sprint to close down a striker.

The burst of pace to reach a through ball.

The acceleration needed to recover defensively.

Those moments often separate winning from losing.

And that's before environmental factors are added into the equation.

Several host cities are expected to present significant heat and humidity challenges, while matches in Mexico will introduce altitude into the mix.

"In an ideal world, teams would spend weeks acclimatising to altitude," Clarke says. "But that's not really possible in a tournament where teams are moving between different locations. In reality, they'll often have to fly in, play and move on."

That means squad management may become one of the most important tactical tools available to coaches.

For decades football has focused on finding the best starting eleven.

This summer may be about finding the best twenty-six.

"The teams with the greatest squad depth could have a real advantage," Clarke says. "If you can replace a great player with another great player, fatigue becomes much less of a problem."

Perhaps surprisingly, one of the biggest performance risks isn't necessarily physical at all.

It's cognitive.

Football supporters often notice when a player looks tired physically.

What they don't see is what's happening inside the brain.

As fatigue accumulates, concentration and decision-making can begin to suffer. Small lapses in judgement can prove decisive at the highest level.

"The physical aspect is important, but so is the cognitive side," Clarke explains. "As blood glucose falls and players become fatigued, decision-making can become impaired. That can influence positioning, concentration and tactical choices."

This is where nutrition becomes critical.

For years carbohydrates have suffered something of an image problem. Protein has become the nutritional superstar, while carbohydrates are often viewed with suspicion.

For elite footballers, however, carbohydrates remain fundamental.

"If you're talking about high-intensity exercise like football, carbohydrates are king," says Clarke.

It's a statement that may surprise many recreational athletes, but it reflects the reality of elite performance.

Repeated sprinting relies heavily on muscle glycogen stores. As those stores become depleted, performance begins to decline.

That is why players spend so much time carefully managing carbohydrate intake before, during and after matches.

Protein remains equally important, but for different reasons.

"Protein is essential for recovery," Clarke explains. "The key is understanding that protein and carbohydrate have different jobs. One helps support recovery and repair. The other provides the fuel needed to perform."

Alongside carbohydrates and protein sits another supplement that Clarke believes deserves its reputation.

Creatine.

"Creatine is one of the most evidence-backed supplements available," he says. "It supports high-intensity performance, and the emerging evidence around cognition is really interesting as well."

As football becomes faster, more demanding and increasingly decided by small margins, those marginal gains become more valuable.

• Hydration strategies are becoming more personalised.
• Nutrition plans are becoming more individualised.
• Recovery protocols are becoming more sophisticated.

The future, Clarke believes, lies in treating every player differently.

"The more individual we can be, the better," he says. "Players respond differently to training, hydration, nutrition and recovery. The more we understand the individual athlete, the more effectively we can support performance."

Ultimately, however, the fundamentals remain remarkably unchanged.

• Recovery.
• Nutrition.
• Sleep.
• Hydration.
• Preparation.

The science supporting those pillars continues to evolve, but the principles themselves remain timeless.

And when the World Cup reaches its conclusion and one captain finally lifts the trophy, the winning team will almost certainly have world-class players.

But they may also be the team that managed fatigue better than everyone else.

Because in modern football, talent wins matches.

Managing fatigue wins tournaments.