It’s so hardcore even its Californian creator warned of the risks, so why are Britons flocking to CrossFit classes?

To be told that you need to put more oomph into your 50th deep squat in succession and then move swiftly on to your 500m timed row is enough to make your legs buckle and your mouth froth with effort even if they weren’t already. Given that I am running a marathon in April, I consider myself reasonably fit and yet I am floundering in front of a group of ordinary office workers who are showcasing unbelievable levels of endurance and strength. But then I am attempting a workout of the self-styled fitness elite, adherents to a punishing exercise regime called CrossFit, a motto of which is:

“Your workout is our warm up”.

Around us in the huge warehouse in Stockport where we are pushing ourselves to extremes are tools with which regular CrossFitters are all too familiar: kettlebells, free-weights, climbing ropes and Olympic rings on which to perform a variety of full-body pull-ups. It all adds to the sense that you are entering the domain of the super-fit. There is a “spit and sawdust” feel to a CrossFit session that you don’t get at a regular gym; no mirrors, indeed nothing swankier than a wall-mounted stop-clock to time your session. On a board in front of us is chalked our Workout of the Day, or W.O.D, something that changes with each visit and that is designed to take the body by surprise. Whereas we have pull-ups, press-ups and sit-ups to contend with, a W.O.D could include relays carrying sandbags, endless kettlebell swings or rope-climbing to exhaustion. With a discernible degree of fear in their eyes, regulars mention the Dirty Thirty or, worse, the Filthy Fifty — 30 or 50 repetitions of moves such as box-jumps, walking lunges and 400m runs. Check out the website, the holy grail of participants, and the exercises are more extreme, more bizarre.

Images are posted of CrossFitters dragging their children along in tyres attached to harnesses, performing ten rounds of a deadlift with a toddler or, in one case, a fully-grown woman. They weightlift outside. In the snow. They haul rocks and lift whole tree trunks as they would a barbell at the gym. I am beginning to feel that I have been let off lightly.

Our CrossFit instructor, Carl Dickson, is forcefully encouraging with his instruction rather than barking out orders. “I’m not here to make someone do something,” he says. “Everyone here comes back because they can see after just a few sessions that it really works.” Dickson says that CrossFit addresses all aspects of fitness, making your body functionally as near to perfect as it can be or, as CrossFitters like to put it, in a state of “physical preparedness”. Sessions are short, usually lasting no more than 45 minutes, but in that time you will work on the ten general physical skills considered essential to the approach: respiratory endurance, stamina, strength, flexibility, power, speed, agility, balance, coordination and accuracy.

“We use power-lifting and Olympic weightlifting techniques, bodyweight exercises and medicine-ball throwing, but only at a level to suit your current ability,” Dickson says. “The things about CrossFit is that anybody can improve by doing it. We have 80-year-olds who come regularly and just want to stay healthy. They do it at their own level.”

There are around 70 CrossFit “boxes” — the name for the spaces in which the sessions are performed, be they gyms or modified store-cupboards — around the UK, but that figure is expected to rise significantly as the company — backed by Reebok — rolls out classes across the nation from next month.

Membership to the programme costs about £65 a month for unlimited sessions, although Dickson recommends completing at least three a week for maximum benefit.

The arrival of CrossFit reflects a shift within the fitness industry away from “softer” approaches, such as yoga and Pilates, towards workouts of higher intensity and greater reward.

With its expectation that participants will overload their bodies, executing movements with as much weight or effort as they can bear, CrossFit occupies the extreme end of the workout spectrum. What strikes me most is that everyone I speak to enthuses about the CrossFit community, the network of support that exists both within their own group and across the globe. It seems more of a lifestyle approach than merely another fitness trend. Members consult the website, often daily, for advice, guidance and demo-videos.

It has its own social network, its own role models and its own champions, the CrossFitters who outperform all others. They share tips on diet — the Paleo, caveman-style approach that cuts out over-processed food is popular and in keeping with the unadulterated ideal of CrossFit. To an outsider, the level of group cohesiveness can be disconcerting. Of course, there are many approaches to fitness that acquire a devout following. Within yoga, running and even at the gym, there are those for whom dedication to their chosen activity appears to have taken them to a higher level. But CrossFit is something else, a nudge closer to the cult-like.

It has a real-life spiritual leader in its founder, Greg Glassman, who guides his disciples from afar — California, to be precise — and who is referred to by those who qualify in the instruction of his training methods simply as “Coach”.

A former gymnast, Glassman first put his training theories online in the form of a workout programme back in 2001. Its popularity in America soared and CrossFit is now practised at more than 2,000 venues, as well as by fire departments and military organisations such as the Canadian Armed Forces, US Marines and the Royal Danish Life Guards.

It seems the UK, too, is ready. Michelle Edgley, a 29-year-old customer service assistant from Manchester, took part in her first CrossFit class in September and has since become a convert. “It was very daunting the first time I tried it,” she says. “But I’ve stuck at it and now do four to five sessions a week. My body has changed shape completely. I’m amazed at what I can do compared with when I started.”

Like Edgley, Tom Costello, 21, a keen hockey player and another regular at the Stockport sessions, records each of his workouts in a CrossFit diary and can tell me precisely how he has progressed since he started six months ago. “I couldn’t lift my own weight, couldn’t do a single pull-up,” Costello says. “Now I am doing at least 20.”

Not all reports of the effects are as glowing. Among extreme CrossFitters, injury is not uncommon. One former army ranger in America was performing 50 repetitions with a 44Ib kettlebell as part of his CrossFit session a few years ago when he ended up in hospital with rhabdomyolysis, caused when muscle fibre breaks down and the ensuing proteins are released into the bloodstream, effectively poisoning the kidneys.

He recovered and six months later returned to training with the programme. Coach Glassman has been quoted in The New York Times as saying: “It can kill you, I have always been completely honest about that.” What doesn’t kill you, though, makes you stronger. A mantra for CrossFit, if ever there was one.

“It is hard work, but you don’t get anywhere without hard work,” Dickson says. “Put in the effort and the reward is a body that serves you well and a sense of self esteem second to none.” Despite the session’s brevity, my legs were leaden the next day. Inspiration enough to head back for more.

What’s your W.O.D?

A W.O.D. or Workout of the Day starts simply for beginners, but progresses to the unimaginably hard. All should be performed with maximum effort and speed.

Week 1
Deadlift x12;
run 400m; push-ups x15;
run 400m; squat x15.

Week 4
Squat x27; run 400m;
squat x 27; run 400m; squat x 27.

Row 2km; 50 wall-ball shots with a 20lb medicine ball; row 1km;
35 wall-ball shots with a 20Ib ball; row 500m;
20 wall-ball shots with a 20Ib medicine ball.

OR 600m run; 15x95lb squat clean overhead lift “thruster”. Repeat five times.

OR Complete as many rounds as possible in 12 minutes of: 24in box jumps; 12 reps 95Ib overhead lift “thruster”; six repetitions of six bar-facing burpees (Google for examples).