If not completely revolutionary, Lift: The Movement, in London’s Shoreditch, is refreshing by the standards of most fitness studios. Natural light streams through floor-to-ceiling glass and the music is… jazz? Certainly it’s a far cry from the big-box gym where Lift’s founder, Angus Martin, would emerge from underground on the verge of an anxiety attack, after 12-hour PT shifts being blasted by heavy metal. He half-jokes that it was “like torture”.

In addition to gymnastic rings, hand balancing and Brazilian jiu-jitsu, classes include ‘Motion’, which is ‘movement’ in the flexibility, Animal Flow sense of the word, and ‘Regen’, which counteracts the deleterious effects of our keyboard-bound existences. When Lift first opened in August last year, it ran a ‘Conditioning’ class more in line with the nigh-on industry-standard that is High-Intensity Interval Training. But that was quickly nixed when Martin saw the number of attendees “categorically unprepared” physically for anything so strenuous, but eager nevertheless. “The truth of the matter is that people are fucking themselves up,” says Martin.

Pretty much every fitness studio and gym going offers some variation on the theme of HIIT: for the uninitiated, exercising at around 90 per cent of your maximum heart for short bursts, interspersed with periods of active recovery or complete rest. You thereby clock up more work at an intensity that you couldn’t otherwise sustain. Thanks also to something called raised excess post-exercise oxygen consumption, which means that you continue to burn calories at a higher rate afterwards while you replenish the deficit, you can reap the same fitness and fat-loss results, or even better, faster.

In 2014, HIIT entered the top 20 of the American College of Sports Medicine’s annual industry survey of worldwide fitness trends for the first time, landing straight at number one. Respondents remarked how their clients loved HIIT “because of the short time”, but cautioned of its elevated injury risk and unsuitability for some. HIIT has remained in the top five ever since; this year, it’s second behind wearable tech. The 2020 edition of the survey notes: “Despite warnings by some fitness professionals of potentially increased injury rates using HIIT, this form of exercise has been popular in gyms all over the world.”

Lift’s Martin fucked himself up through youthfully ignorant bodybuilding and powerlifting in order to get bigger and stronger for amateur rugby. Following elbow reconstruction surgery and extensive rehab, he’s keenly interested in un-fucking up both himself and others, and averting future up-fuckery – which is where, he says, “HIIT culture” is corralling us: “I don’t know anybody who works in an office and does exercise who isn’t in pain.”

Painstaking corrective exercise in order to repair a bio-mechanical car crash, or swerve one down the road, is a harder sell than the instantly gratifying endorphin rush and calorie conflagration of a HIIT class, as Martins ruefully admits. He likens such quick fixes to sugar or fast food. By contrast, mastering the rings, handstands or jiu-jitsu, and developing the strength, mobility and skill required in the process, is gratification of the very much delayed, journey-is-the-destination sort. “That’s the difference,” says Martins, who has “patience” tattooed on his arm. “Black belt, 20 years; HIIT class, 45 minutes.”

Indeed, what Lift and a small but growing movement are pushing could be compared to slow food, slow journalism or slow living. Something more considered, that values quality over quantity and quickness, long-term over short. In other words, ‘slow fitness’.

Slow fitness is another term for what London-based trend forecasting agency The Future Laboratory has dubbed “conscious deceleration”. “Wellness has been in accelerator mode,” reads its Health & Wellness Futures 2019 report, published in July last year. “As a society we have been conditioned to equate being busy with being important and, as a result, wellness has been used as a tool to pack even more into our already saturated lives.”

But as the Future Laboratory’s report observes, the path to personal optimisation, “aiming to be fitter, stronger or more zen”, can be a road to burnout. Slowly but surely, we’re realising that harder and faster aren’t always concomitant with better and stronger: “There is a growing desire to replace this quick-fix mentality by focusing on slowing down to build up long-term endurance and allowing space to breathe, both physically and metaphorically”.

Low-Intensity Steady State, typically exercising for half an hour or longer at around 50 per cent of your maximum heart rate, or a pace where you can comfortably talk, is back in the conversation, having been dismissed as a waste of time. (Before jogging catalysed the fitness boom of the Seventies, strenuous exercise was believed to be bad for your health and negatively associated with lower, working classes.) Low-Impact Interval Training, which can still be fairly intense but less stressful on your body and mind than HIIT, is also lit, or rather LIIT. And there are whole workouts, classes, even studios dedicated to stretching or active recovery: moving around just hard enough to get the blood flowing, lubricate any stiffness and help repair the damage from your last HIIT session.

Slow fitness doesn’t have to mean exercising slowly. Another word for ‘conscious’ is ‘mindful’, which is increasingly prefixing any and every kind of activity, never mind exercise, but particularly ‘running’. That can be in the guise of on-the-move guided audio meditations like those Headspace recorded for the Nike Running Club app, but truly mindful running is perhaps more about unplugging from technology (another wider movement) and tuning into your body. In 2018, ASICS unveiled a 150m “blackout track” in east London to train the mind by minimising all but the most essential stimuli.

“For me, mindful running really comes down to mind-body connection,” says Charles Oxley. (Not that they’re really separate, as he points out.) A member of ASICS’s “Sound Mind Sound Body Team” for that event, Oxley is more commonly a coach with Power Speed Endurance, the company founded by pioneering coach Brian MacKenzie. Over a decade ago, MacKenzie noticed that many distance athletes were mortgaging long-term performance and health for short-term performance and looks, and being ground down if not crushed; he proposed a controversial skill-over-volume approach for building endurance. One of PSE’s enduring principles is that intensity must be earned: only when you can maintain the skill – running, lifting, whatever – at intensity can you add volume.

Our bodies are constantly giving us information while we run, Oxley explains: if you’re going too fast, or loading your knee incorrectly. But we’re often not listening, or thinking about anything other than hitting our target pace or distance as dictated by our training programme, app or some other external factor. Finishing in a heap is a badge of honour. Instead of running ourselves into the ground, we should be asking our body what pace or distance it can handle. Being mindful, he says, is being conscious of what you’re doing, and doing what you really need, rather than “what you think culture is demanding from you”.

“We suppress a lot of things,” says Oxley. “We’re a culture that is professional at distraction.” Self-reflection is “terrifying” for many people, who’d rather just do what others are and hopefully find meaning, purpose, a tribe; they chase after short-term goals that don’t fulfil them instead of asking themselves what they really want. “And this is a bigger topic than just slow fitness and high-intensity,” he says. “This is a much more global issue.” Sooner or later though, the signals grow so loud that they can’t be ignored.

The rise in recent years of ever more hardcore forms of recovery, from foam rolling to , compression therapy (a pair of inflatable trousers that squeezes your legs like toothpaste in a tube) and cryo, is an indication, Oxley contends, that we’re hitting it too hard. Pain, after all, is “a useful signal” to stop doing something: “It’s your body saying, ‘Hey, stay away.’” Yet in fitness as in other areas of life, we plough on regardless of the warning signs – in the case of exercise, injury, soreness, tiredness, low mood, raised stress, disrupted sleep, impaired immunity, fat retention, muscle breakdown, gastrointestinal issues and stalled sex drive (a silent epidemic among instructors teaching multiple HIIT classes a day, Oxley says).

Stopping, or at least “consciously decelerating”, is not yet widely culturally acceptable. “I think a lot of people still aren’t confident to be like, ‘I need to go slower,’” says Oxley. “Culture will always trump physiology.” And what culture currently defines as fitness is “lifting heavy weights, going really fast, lying in a pool of sweat… It’s dark, it’s dingy, it’s just absolutely burying yourself.” Clearly that appeals to some, but it puts many more off.

Exercise is vital for health, both physical and mental, and reducing your risk of not being dead. But it doesn’t have to mean killing yourself in a HIIT class or ten-mile run, as Oxley tells attendees at the free Round Table for Change discussions to improve mental health through exercise and breath work that he helps facilitate. It’s “a real struggle” to convince them as much, and to dispel their images of Nike adverts and CrossFit videos, but exercise can also be, as he tells them, something that you do for an hour that feels like five minutes: “Going for a walk, rock climbing, gardening, whatever.” (Another danger of HIIT is that it’s perceived as a magic supplement that compensates for a woefully deficient “movement diet” when we should be spending more time being active, not less.)

Slow fitness and serious exercise aren’t mutually exclusive either. Continuously self-improving author James Clear, whose 2019 international bestseller Atomic Habits is all about how “tiny changes” elicit “remarkable results” over time, champions “slow and easy gains”, which he calls “the greatest weightlifting lesson I’ve learnt”. Our societal obsession with here-and-now achievement leads us to overlook slow, consistent progress, he maintains, even though that would ultimately lead to greater achievement. (A former athlete, Clear was hit by a flying baseball bat in high school, placed in a medically induced coma and spent months relearning basic functions like walking; by the time he graduated college, he’d been named as a pitcher in ESPN’s Academic All-America Team.)

To illustrate, Clear suggests adding 1lb to your favourite lift every week: “You are not allowed to do 2lb. Only 1lb.” Slow and easy, yes, but then that’s no bad thing. “For some reason, society has convinced us that if your heart rate isn’t above 150 beats per minute and you don’t feel gassed at the end of your workout, then you haven’t done yourself any good,” he writes. “I disagree. If you actually add a little weight each week and don’t miss workouts, then it will get hard enough, fast enough. Trust me.” Not only that, but in a year, you’ll be lifting 50lb more; in two years, 100lb: “How many people do you know who are lifting 100lb more than they were two years ago? I don’t know many.”

More common is doing too much, too soon, because of impatience, ignorance or trying to compensate for inconsistency with intensity; the result is inflammation, injury and inability to lift yourself off your sofa. But if you want to get fitter, and maximise your potential, then building the gym-going habit and not missing workouts is “the most important thing” in Clear’s view.

“It’s all a recovery game,” says Oxley, who quotes one of PSE’s mantras: “It’s not how much work you can do, it’s how much you can recover from.” We see how athletes train and rush to emulate them, but we don’t see the support teams that drive them around, prepare their meals and do their washing while they have a massage or nap. Exercise is a form of stress and has to be balanced against other stressors in your life. Because of their lifestyles, a lot of Oxley’s clients can only really recover from one intense session a week at the outset. They insist that they can do more, but first they have to demonstrate to him that they can eat well, stop working until midnight and get eight hours of sleep.

HIIT isn’t inherently bad, as Oxley is at pains to stress. (Neither is stress, come to that.) On the contrary, HIIT is incredibly effective, which is partly why it has become insanely popular. But you can have too much of a good thing, especially if you’re not in a fit state to handle it: as another saying goes, the difference between medicine and poison is dose. Penn State University recommends no more than 30 to 40 minutes above 90 per cent of your max heart rate per week to avoid overtraining. Or, you know, listen to your body.

That won’t stop all things high-intensity eventually being labelled bad, as Oxley fears, but that’s just human nature: “We’re going to go too far into the high-intensity now, we’re going to go too far into the recovery and then we’re going to realise in about five or six years that it’s somewhere in the middle.” We’re slow on the uptake, if nothing else.

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