Ice baths and cryotherapy are the most fashionable fitness accessory in football right now. Why? Because the Premier League is no longer won based on a team's strength, speed, stamina or skill set. Instead, it's won based on a team's ability to recover and avoid injury.
This is a bold claim, I know, but it's widely believed players in the Premier League play more games and cover more miles than their European counterparts in the Bundesliga and La Liga. So much so that Liverpool's Jurgen Klopp has been very outspoken in the media about the sheer volume and frequency of matches English footballers are expected to play.
After Belgian striker Divock Origi was sidelined by the same hamstring injury as Martin Skrtel, Jordan Rossiter and Daniel Sturridge at the end of 2015, Klopp was quoted in the Independent saying, "Hamstring is the s--t word. It is always hamstring, hamstring, hamstring—that is the intensity of the game and fixtures."
It is a view reinforced by former England manager Sam Allardyce who, as reported by ESPN FC, said, "English football might be the richest around, but its concurrent status as the most physically demanding in European football (where players habitually run more than 10km a match) risks the physical well-being of its participants."
But can ice therapy offer sporting salvation for injuries that currently plague the Premier League, and is there any science to support its use? Or are baths filled with ice the "magic sponge" of the 21st century, doomed to fade into footballing obscurity along with oranges at half-time?
Exploring the latest research relating to football's secret sports science, here we examine the impact cryotherapy has on players preventing, and more quickly recovering from, injuries, and the teams successfully using it.
Ice Therapy: The Science and Studies
Running close to complete fatigue for 90 minutes, every week, for 38 matches throughout the season, will take its toll on the body. To quote research from the Journal of Emergencies, Trauma and Shock: "Training and competition creates an overload to stress the body, which in turn produces fatigue."
The research goes on to say, "What athletes do after their exercise and work-out regime can affect their muscle recovery." Which is why the strength and conditioning staff at top-flight teams will advocate stretching, sufficient recovery time, physiotherapy and—if you're Everton Football Club—custom-made whey protein recovery shakes to ensure they're fit, fresh and injury-free once the whistle blows for their next fixture.
But despite being a relatively new recovery method, the Scandinavian Journal of Medicine and Science in Sports states, "The use of cryotherapy, i.e. the application of cold for the treatment of injury or disease, is widespread in sports medicine today," and claim it is "used to reduce the recovery time as part of the rehabilitation programme."
The American Journal of Physiology seems to agree, stating, cold-water immersion "after resistance exercise allows athletes to complete more work during subsequent training sessions, which could enhance long-term training adaptations."
But How Exactly Does It Work?
Well, despite the BBC suggesting Leicester City's historic title win was partly due to cryotherapy, it must be noted modern medicine doesn't fully understand how it helps. But, equally, modern medicine still doesn't fully understand the intricacies of the entire immune system either.
Integral to a footballer's recovery, the immune system is made up of a network of organs, hormones and cells that all work in synergy to keep the body fit, healthy and happy. But from myriad peer-reviewed publications in exercise immunology that have been published since the formation of the International Society of Exercise and Immunology in 1993, it appears scientists hold their hands up and acknowledge more conclusive findings are needed.
But despite the lack of clarity, researchers from the Department of Physiology at the Australian Institute of Sport believe, "The ice bath will cause constriction of blood vessels. This has been suggested as a mechanism that helps with the flushing of waste products, such as lactic acid, out of the affected tissue."
In contrast to ice baths, cryotherapy chambers—which come in whole-body versions or those that encapsulate all but the head—net similar results without the exposure to ice-cold water, using refrigerated cold air and/or liquid nitrogen to achieve the temperatures. The BBC's Alistair Magowan described the freezing temperature's role in the process as spurring "blood withdrawn back to the heart before new oxygenated blood flushes into the player's muscles."
Acknowledging both the sports science magic and mystery, Leicester forward Jamie Vardy told Magowan, "It's absolutely freezing, but it helps you in your recovery, so fair play to the club for getting it. I don't think even some of the brainiest men in the world would understand the name of the stuff they've been doing but they've been working on me all week."
The role cold therapy played in Leicester's historic title win also seems supported by the side who followed them as champions, Chelsea. The Sun quoted Asmir Begovic, who has since moved on to Bournemouth, as saying, "An ice bath always comes good at the end of the day. We know it's going to benefit us in the long run."
In short, cryotherapy may help, but we just don't know exactly how yet. Further, the process carries some small risk for frostbite or even inert gas asphyxiation if not properly managed and monitored. So to quote the Journal of Emergencies, Trauma and Shock, perhaps a "holistic approach to recovery will give a better response rather than an isolated recovery technique."
Basically, more players and coaches are beginning to embrace the all-inclusive, mysterious healing power of immersing your body in temperatures of minus-135 degrees Celsius for up to four minutes like Vardy.
Ice Therapy and the Immune System
The media are very quick to report on obvious injuries, those where fans are able to physically see why a player is unable to start. Whether it was Wayne Rooney's head injury as reported by BBC or David Busst's leg break when Coventry City played Manchester United in April 1996 (which was so severe it still makes the headlines today).
But what doesn't get as much airtime is when players simply become sick from overtraining.
However, during the 2014 FIFA World Cup, Michael Davison reported on that very issue for the Telegraph: "This has, though, been the most physically and mentally demanding World Cup in years. The heat stress, low-quality sleep patterns and travel will have depleted the energy stores of the players: the eventual winners are likely to have clocked up between 7,500-12,000 miles."
The report added, "We should not, therefore, be surprised that Spain bowed out early. Many of their players have been on a three-year conveyor belt of competitive action, including the European Championship in 2012, the Confederations Cup last year and two of their domestic teams reaching the Champions League final."
But Can an Ice Bath Really Help?
A study published in the European Journal of Applied Physiology and Occupational Physiology certainly thinks so. Scientists wanted to test if an athlete's immune system could be positively improved by a "noninfectious stimulus." The stimulus they used in the study was basically subjecting athletes to six minutes of ice baths three times a week.
After six weeks, what they found was the cold triggered the body's "fight or flight" response, which in turn brought about a "small, but significant, increase in the proportions of lymphocytes." Lymphocytes are the body's cells that fight infection, so having more of these during a season of many miles and many games would be a welcome physiological adaptation.
As things stand, sports scientists still don't fully understand how ice baths—or the human immune system—work to aid recovery. Which is why, until modern medicine provides more answers, the "holistic approach to recovery" mentioned in the Journal of Emergencies, Trauma and Shock coupled with the intuitive—but not fully informed—optimism of Vardy and Leicester City, could be a valuable tool for players' recovery and subsequent sporting success.
All quotes and information obtained firsthand unless otherwise indicated.