The exercise phenomenon born in a prisoner-of-war camp

Knockaloe, an internment camp on the Isle of Man, was the unlikely setting for the development of Pilates – a regimen that continues to acquire devotees to this day. And its inspiration was unlikelier still.
Photograph by Design Pics, National Geographic Image Collection
By Yosola Olorunshola
Published 29 Nov 2021, 10:07 GMT, Updated 30 Nov 2021, 16:10 GMT

BETWEEN images of the poppy fields and sodden trenches that shape the collective memory of World War I, the presence of prisoner of war camps in the British Isles do not immediately spring to mind. But over the course of the war, Britain interned almost 116,000 people in camps across the country, from London’s Alexandra Palace to a former farm on the Isle of Man. Among those who found themselves at the latter was a German boxer and circus entertainer named Joseph Pilates.

The enemy in our midst 

Like thousands of German civilians living in Britain in the prelude to the war, Pilates – born in Mönchengladbach in 1883 – found himself in the wrong place at the wrong time. As conflict clouds gathered, anti-German sentiment had been growing, casting suspicion on the German men and women living and working in Britain – a community of approximately 57,000 people by 1914

Within 24 hours of declaring war on Germany on 4 August 1914, the British government issued the Aliens Restrictions Act, which defined all German nationals in Britain as “enemy aliens.” As a result, any German male of military age found in Britain could automatically be arrested or interned, due to the perceived threat posed to the British people.

As a single man with limited English, and an itinerant one travelling with the circus, Pilates was an easy candidate for suspicion. While living in a guest house in Blackpool, he was forced to register himself as an “alien” at a local police station. Soon after, he was arrested and sent for questioning at Sandhurst, before being transferred to temporary internment sites in Jersey, then Lancaster. 

Knockaloe internment camp, Isle of Man, as it was in 1915. At peak capacity, the camp – ...

Knockaloe internment camp, Isle of Man, as it was in 1915. At peak capacity, the camp – described as kriegsfangenenlager, or 'prisoner-of-war camp' in the caption of this image, drawn by an internee – contained over 23,000 civilians. Most were German, with some Austrian-Hungarian and a small number of Turkish internees. Pilates was believed to have occupied camp 4, in the foreground of this drawing.

Photograph by Knockaloe Charitable Trust,

Pilates was one of the earliest civilians to become a prisoner of war in Britain during World War I, but thousands of arrests followed. In May 1915, a German submarine torpedoed the Lusitania, a luxury passenger cruiser sailing from New York to Liverpool, in an infamous act that killed more than 1,000 people.

This attack on ordinary civilians intensified fears of “the enemy in our midst.” Although the Lusitania was certainly a civilian vessel, the Germans felt justified in their attack as the ship was carrying a cargo of around 173 tons of rifle ammunition and shells. But the unprovoked nature of the attack outraged the British public and triggered a wave of xenophobic riots against German homes and businesses in major cities like Liverpool, London and Manchester. Following the tide of public pressure, the British government quickly expanded the Aliens Restrictions Act and introduced a knee-jerk policy of mass civilian internment for male “enemy aliens” between the ages of seventeen and 55. By November 1915, the number of civilian prisoners of war had reached 32,000. 

The vast majority were held at Knockaloe Internment Camp (pronounced Knock-ay-low) on the Isle of Man, which housed 23,000 men at its peak. Pilates was transferred to Knockaloe on 12 September 1915 and it was here, in the depths of confinement, he claimed his unique exercise system was born. 

Think like an animal

From its floor-based stretches to its machine-like conditioning equipment (often compared to medieval torture devices), it is perhaps easy to imagine how the experience of wartime confinement provided the inspiration for the exercises that evolved into Pilates. 

A closer view of accommodation at Knockaloe, where male prisoners of British opposition nationalities between the ...

A closer view of accommodation at Knockaloe, where male prisoners of British opposition nationalities between the ages of 17 and 55 were interned during World War I – an act spurred on by the sinking of the civilian ship Lusitania by Germany in 1915, causing local protests against the presence of German civilians in Britain. Joseph Pilates arrived in 1915. 

Photograph by Knockaloe Charitable Trust,
A view inside one of the internment huts, painted by a resident. Life at the camp ...

A view inside one of the internment huts, painted by a resident. Life at the camp was basic, but there was a culture of sorts – with an orchestra, sports clubs, a library and various artists circles within the 3-mile boundary wire of the camp.

Photograph by Knockaloe Charitable Trust,

In a rare 1962 Sports Illustrated profile published during his lifetime, Pilates spoke to the journalist Robert Wernick about his time on the Isle of Man. He describes the monotony of life on the island, where he spent days observing the mental and physical deterioration of his fellow prisoners, “with nothing to look at but an occasional starveling [sic] cat streaking after a mouse or a bird.” In his eyes, the weakened energy of the prisoners contrasted with the dynamism of the stray cats that loitered in the prison. 

“Why were the cats in such good shape, so bright-eyed, while the humans were growing every day paler, weaker, apathetic creatures ready to give up if they caught a cold or fell down and sprained an ankle?” he asked. 

According to his account, Pilates began observing the cats and analysing their motions intensely, realising that their constant stretches were the key to their vitality. Inspired by these movements, he began to develop a series of exercises to stretch the human muscles, and claimed he tested them on his fellow inmates, who were transformed by the results. And so “Contrology”, as the exercise system was initially known, was born – or so the story goes. 

Physical exercise – necessarily confined to small-area sports such as boxing or gymnastics – were common ...

Physical exercise – necessarily confined to small-area sports such as boxing or gymnastics – were common at the camp, such as this gymnastics demonstration in 1915, which took place not long after Pilates arrived. 

Photograph by Knockaloe Charitable Trust,
Pilates' observation of feral cats moving around the camp – and how they stayed in condition ...

Pilates' observation of feral cats moving around the camp – and how they stayed in condition on meagre rations – was said to be fundamental in the development of his technique, which he called Contrology. With resistance, balance and poise critical to the discipline, it shared many qualities with gymnastics, of which there was an eager following at Knockaloe. 

Photograph by Knockaloe Charitable Trust,

In this interview, Pilates made some bold claims about the effectiveness of Contrology. For instance, he told Wernick that the prisoners he trained “ended the war in better shape than when it started, and when the great influenza epidemic came sweeping over all the countries that had fought in the war, not one of them came down with it.” 

From the vantage point of the COVID-19 pandemic, a miraculous exercise offering protection from a flu virus might sound like fake news; Pilates tirelessly sought to promote Contrology as a cure-all system, but there is of course no evidence for the claim. 

‘Barbed-wire disease’ 

But Pilates’ description of the atmosphere in the camp certainly rings true to accounts of life at Knockaloe. From his inspections of First World War internment camps, Swiss physician Dr. Adolf Lukas Vischer coined the term “barbed-wire disease” to describe the toll of confinement on the mental health of the prisoners he witnessed.

Characterised by boredom, confusion, clouded thoughts and amnesia, the symptoms of barbed-wire disease echo Pilates’ reflection on his fellow prisoners’ state of mind. The counterpart to the lingering effects of “shell shock” experienced by those on the front line, barbed-wire disease embodied the trauma of war for those locked up far away from the battlefields. 

The prisoners were allowed to take part in activities to ease the psychological burden. Music, theatre and sport societies were a key feature of life at Knockaloe, and a prisoner-run newspaper provides a rare glimpse of Pilates’ time at the camp. An article published in January 1917 lists him as the referee of a controversial boxing match, confirming that he did put his sporting background to use. 

But beyond this handful of evidence and Pilates’ own anecdotes, there is little surviving detail on his life at Knockaloe. 

Joesph 'Joe' Pilates in his New York studio with a client - part of a series of images shot by photojournalist I.C. Rapoport in 1961, when Pilates was 78 years old and still a keen student of his own method.

Photograph by I C Rapaport, Getty

“There’s an awful lot of maybes,” says Alison Jones, the chair of the Knockaloe Charitable Trust, a voluntary organisation on the Isle of Man which seeks to preserve the stories of the camp's internees for future generations. “Later in life, he talked about working in one of the hospitals in the camp and using the springs on the hospital beds to develop early forms of what became the classic Pilates equipment. All of this is certainly plausible, but we just don’t have specific evidence as yet.”

“You have to remember that there were over 30,000 men who came through the camp. We’re always hearing from descendants of former internees who have some new documents or artefacts to share. Just because we don’t have more specific details on Pilates yet, doesn’t mean something might not come through.” 

The art of reinvention 

After his eventual release in March 1919, Pilates was repatriated to Germany at the age of 36. From accounts of these years, exercise continued to be his main trade; he spent some time supporting the Hanover police in physical training and working with dancers dealing with physical problems. This work brought him into contact with the celebrated dancer Hanya Holm, who later emigrated to New York and became one of the “Big Four” founders of American modern dance. Holm would prove to be a valuable connection, as Pilates also had his sights set on more distant horizons. In 1926, he joined the long flow of Europeans setting sail for Ellis Island, New York, in the hopes of building the immigrant dream. 

By this point, Pilates was in his early forties and ready to embark on a brand new life. On the way to New York, he met a German woman named Clara Zuener who became his life-long partner, both romantically and professionally. Together, they led a studio that would instil the principles of Contrology into a small but loyal and influential band of followers. 

“Joe was transfixed watching large caged cats... I realised he was watching himself in that enclosure.”

John Howard Steel

Their first gym – the Joseph H. Pilates Universal Gymnasium – opened in 1927 at 939 Eighth Avenue, where it remained for more than forty years. At the time, there was no gym culture as we know it today and Pilates was deeply critical of the American lifestyle, believing he offered a unique antidote to the pressures and temptations of modern living. His contacts in the dance world attracted an artistic clientele to the studio, including the choreographer Martha Graham. Over the next two decades, he tried to expand his philosophy of exercise beyond dance circles, publishing two works: Your Health (1934) and Return to Life Through Contrology (1945) to promote Contrology as a holistic system for the mind and body. 

Pilates was determined to persuade the general public and the medical establishment that Contrology was the most effective medicine. Always prone to a bold sales pitch, he promised that: “Return to Life fully explains how you can successfully achieve your worthy ambition to attain physical fitness in your own home and at only nominal cost.” But by the time of his death in 1967, he remained disappointed that the medical establishment still hadn’t caught on to his revolutionary ideas. 

The man and the myth 

John Howard Steel, one of Pilates’ last surviving students and the author of Caged Lion, a first hand account of their unlikely friendship, describes Pilates’ obsessive streak. 

“All he cared about was Contrology. He was obsessed with this one thing. That’s all that mattered in his life, in every conversation,” Steel told National Geographic

“It was all he had. You have to remember that he arrived in New York, around 40 years old, without any credentials. He wasn’t a doctor, and he didn’t have a job worth talking about. He put his foot down on Ellis Island and thought ‘I’m going to start all over again.’” 

Steel first met Pilates in 1963, when his glory days as a therapeutic luminary of the dance world had faded. Pilates was in his eighties at this point, but still had the build of “a boxer ready for a fight.” Gradually, they forged a friendship akin to a grandfather and grandson; but although Pilates invited Steel closer into his life than most, he remained as enigmatic as ever. 

Pilates created several instruments to assist his regime – including the 'gym in a doorway' (also known ominously as the 'guilliotine'), the Spine Corrector, the Reformer and the Trapeze Table, often given the nickname 'Cadillac' to denote the comfort of more refined versions. All were equipped with various resistance-training implements, many of which can still be bought – such as this Cadillac, manufactured by the Byron Bay Pilates Co – for enthusiasts of Joseph Pilates' methods.  

Photograph by Byron Bay Pilates Company

“He never talked about anything in the past. He erased it. For Joe, the past simply didn’t exist.” 

As a result, there is still plenty of mystery between the man he knew as “Joe” and the real Joseph Pilates. What really took him to Britain just before the outbreak of war? Was he a circus entertainer or did he have ties to the military? How did he fund his trip to New York? What family, if any, did he leave behind? 

Whatever the answer to these questions, Steel accepts that the experience at Knockaloe did shape Pilates forever. In Caged Lion, he recounts the many times he accompanied Pilates to Central Park Zoo:

“Joe was transfixed watching large caged cats,” he writes. “Every time an animal made a move that caught his attention, he would tap me on the leg and point it out. He would then tell me why the animal was doing what it was doing, and how he had incorporated that stretch or exercise into Contrology… I realised he was watching himself in that enclosure. He knew what it was like to be caged.” 

This anecdote echoes Pilates’ memories of the Knockaloe cats, and highlights how the experience of confinement was essential to his understanding of the body and movement. Although he died in relative obscurity, his early followers believed Pilates had found something worth preserving.

Over the 1970s and 80s, former students continued to practise his method, adapting the strict exercises for different needs, opening studios beyond New York and modernising the equipment. However, this evolution was not a linear process. By the 90s, disputes over who could use the Pilates name split the already loose community, culminating in a legal battle that ended in October 2000. The outcome of the case prevented any one person from monopolising the term ‘Pilates’, meaning it referred to a method of exercise that anyone could practise. Today, it is practised by millions across the world and has exploded into a multi-billion dollar industry. 

Reflecting on Pilates’ enduring legacy, Steel points back to his instructor’s experience as a prisoner of war. 

“The method has changed a lot today, but its roots are still in Knockaloe prison,” he says. “Pilates lay there, day after day, trying to figure out how to use his body in no space.

“He had come across something that would help everybody in the modern world because we’re all confined. Most people now spend their time sitting in offices, living in confined spaces. That’s what he discovered – how to live in the prison of life.”

Yosola Olorunshola is a freelance journalist based in London. Follow her on Twitter.


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