“Just try,” Francis says.

“No.” I dangle listlessly from the monkey bar.

“Just one,” he tries again, his palm flat to my mid-back. “I’ll help you.”

I imagine him employing the same tone with his toddler. “I don’t want to!” I spit out, petulantly. I jiggle my legs impatiently, “I want to get down.” Francis smiles. “OK, no worries.” He steps back and I jump to the floor.

Later, at the end of our workout session, he tilts his head sympathetically. “Why wouldn’t you have a go earlier?” I explain that I knew, categorically, that I wouldn’t be able to “heave my bulk over that stupid bar”. That I didn’t have the necessary strength to perform a chin-up, and that I already felt like an idiot – so why add fuel to that fire?

He gives me homework. “Tonight, when you’re in bed about to sleep, close your eyes and breathe through your nose; spend 10 minutes just breathing – lengthening your inhales and exhales – and thinking about which muscles are involved in a chin-up. Imagine those muscles working.”

Francis is a trainer at The Foundry, a swanky gym in London, where I’ve been a member (semi-committedly) for about two years. We are three weeks into my “holistic transformation”, an eight-week programme that is meant to start me on a path towards not just better physical health, but stronger emotional and mental health. As the gym’s cofounder Dave Thomas explains: “Improving your physique can improve your health, both mentally and physically, but it can also have the opposite effect. Being healthy is a much more complex state than having a six-pack.”

Embracing that complexity is about to become one of the biggest trends in the fitness industry. Jessica Harman of forecasting agency WGSN, tells me that in the past year, “the fitness industry has shifted focus from the performance, strength and shape of our bodies to our wellbeing and mental health”. Last year, Re:Mind became London’s first meditation studio – where for £22 a time, dedicated “calmers” guide you through sessions of “energising breathwork”, or encourage you to “focus on good intentions”. In the summer, boutique studio Frame launched an initiative to educate its members about how different styles of movement impact on mood; new gym Mindset opened with an express focus on mental health, and the aim of helping gym-goers overcome “emotional barriers” through fitness; while Barry’s Bootcamp partnered with HUMEN, a charity that works to improve men’s mental health.

“Brands like Equinox fitness club have integrated mindfulness practices into classes as well as employing sleep coaches for members,” says Victoria Buchanan, a researcher at trend forecasting agency The Future Laboratory. High-street gyms like Fitness First have taken up the mantle; last year they partnered with grassroots athletics organisation RunTogether, working to support initiatives such as #RunAndTalk – which aims to improve mental health through running.

The programme I’ve signed up for promises to “transform my body and mind” – leaving me fitter, more motivated, less stressed. In real terms, this means I get personal-trainer-guided workouts (“We’d like you to train five times a week,” Francis says, at which I snort with laughter), nutritional advice (the first piece of which is to cut out one cup of coffee a day) and talks on managing stress. As well as creating a fitness programme for me, Francis checks in on my emotional and mental wellbeing at each session. It’s much cosier than the “abs first, questions later” approach that used to be the norm. The course is not cheap, but it’s easy to apply the same approach to your own regime (see panels below).

To start with, I often feel frazzled – tired, overwhelmed, distracted. As Francis points out, I have a tendency to lose focus halfway through an exercise (or even a sentence). “These are all things we can work on,” he says, soothingly. We discuss goals; I tell him I want to look like a Kardashian – curvaceous but thin, toned but grabbable. “That’s great,” he says and then disregards completely. “I think our first goal is to do a chin-up.” He points out that looking like a Kardashian is counterproductive, as “it’s not an action you can physically take”. Which is how I end up lying in bed three weeks later, meditatively focusing on my biceps and latissimus dorsi (the back muscles used in a chin-up).

Our workouts consist of three sessions of resistance training a week, with increasingly heavy weights, mixed with one or two cardio sessions. They’re always group-based (for the weights sessions, there are just three or four of us; for cardio, it’s more like a class, with around 12 others). Despite the group element, after the first week or so, each resistance workout is tailored to my mood or tiredness level. This is “nourishing movement”. “There has to be an element of enjoyment,” Thomas says. “Feeling positive and excited about what you’re doing is just as important as results. If you’re slogging through, you’re not getting the emotional benefit of exercise.”

Francis doesn’t take every session, but WhatsApps me most days – often about fitness and food, or sometimes just to ask how I am. The cynic in me knows that it’s all part of a service, but it’s encouraging to have the attention. The idea is to offer an impartial and nonjudgmental ear; he’s not a therapist and doesn’t purport to give me solutions to my personal problems, just the opportunity to chat if I want to. In fact, some therapists argue that talking while moving can foster a greater sense of openness – it’s less confronting than sitting opposite someone (whether therapist or friend) – while the endorphin rush and self-esteem boost you get from achieving a fitness goal could make it more likely you reach your emotional epiphanies. Well, that’s the theory. I don’t love discussing my feelings at the best of times, but especially not when I’m halfway through a squat.

Instead, through the weeks, Francis concentrates on correcting “negative self-talk” (“let’s not say ‘heave my bulk’ any more, shall we?”) and thought patterns that, he theorises, are holding me back. “You focus on all the possible negative outcomes. From now on, when you’re in the gym I don’t want you to think about whether something might go wrong.” As well as meditative tasks, he sets homework for me, which includes talking to some of the other people who have signed up for the transformation (“a sense of community will help to keep you motivated,” he explains) and “spending some time on grass”. (“Like running?” I ask. “Yeah, or just walking, or hanging around. Just be outside on the grass for an hour if you can.”) Being in a natural environment, even if it is just a local park, he points out, may help me feel more clear-headed and less stressed.

I work on that chin-up until my arms become sore and my hands are calloused, but often get frustrated. “It’s not a ‘limiting belief’, it’s just a fact of nature,” I say at the end of my first month, no closer to getting my chin over the bar. I find it difficult to do five sessions each week, but do manage three – and I go outside every day, regardless. As Francis points out, “Even walking for 10 minutes is better than nothing, especially if you’re outside.” As the weeks go on, I find I’m drinking less alcohol (an unconscious choice, but since I’m committing to 7am gym sessions, a few wines seem masochistic). My quasi sobriety, combined with the exercise, means I’m also sleeping better. One morning, around six weeks in, I reach over to stop my 5.50am alarm and realise I’m actually looking forward to the session.

In the past, I had always thought of exercise as correcting a mistake: “I’m going to run because I ate five doughnuts yesterday.” Today, I want to exercise because I know it’ll be fun and because moving feels good.

It’s a much gentler way to transform than any I’ve tackled before, and by the end of the eight weeks, I feel less frazzled. I’m not a whole new person, but I do feel good; optimistic, even. I can deadlift more than my body weight, and – as of just a few days ago, I can do one chin-up. Jumping down from the monkey bars, I feel a frisson of pride. I look back on the work it took to get here (the early mornings, the hours of training, the meditative breathing) and allow myself to bask in the achievement. I turn and grin at Francis, who smiles and says: “OK, let’s try for two.”

The experts’ guide to… clearing your mind

Start small In his book Stick With It: The Science Of Lasting Behaviour, psychologist Dr Sean Young breaks lifestyle changes down into dreams (long term), goals (medium term) and steps (short term). If the dream is to get fitter, then the goal might be to run 10k in the next three months, and the first step to get off the bus a stop early and walk the rest of the way. Each step should be small enough that it takes fewer than two days to accomplish. Stimulating the brain’s reward system every two days has been shown to keep us motivated over a longer period.

Reframe anxiety Dealing with chronically high cortisol levels might be the single most impactful thing you can do to improve mental and brain health. From altering our emotional responses, to impairing memory and decision-making abilities, chronic stress physically ages brain tissue. Next time you’re feeling stressed, try telling yourself you’re actually excited. Physically, excitement and stress are very similar (sweaty palms, butterflies, pounding heart) and, according to researchers at Harvard Business School, this simple linguistic switch could be more effective than consciously trying to “calm down”.

Sit up straight Research shows that adopting an upright posture (back straight, shoulders pulled back but relaxed) can, over a day, make someone with mild depressive symptoms feel significantly more positive, less tired and less introspective. The University of Auckland study looked at 61 people with mild to moderate depression and found that good posture was associated with higher self-esteem.

Exercise with others A 2017 study by the New England College of Osteopathic Medicine found that group exercise over 12 weeks improved emotional wellbeing by a quarter and reduced stress levels by the same amount. The same psychological benefits were not seen in those who exercised alone.

Piggyback on other habits According to a study from University College London, it takes 66 days to form a habit. Behaviour-change psychologist Dr Aria Campbell-Danesh, who goes by Dr Aria, recommends tagging your first small steps on to things you already do each day. “If your ritual is to make a cup of tea at 3pm, go for a five-minute walk beforehand. That’s 25 minutes more movement each week – an amazing start if your resolution is to get fitter.”

Cycle to improve memory As Dr Aria explains: “Analysis of four decades of studies found that cycling improves our brain’s ability to store and retrieve memories, both during and after cycling, whereas only a small improvement was found after running.” Results lasted well after the exercise was completed – the cumulative effect of a weekly bike ride could be impressive.

Take up resistance training to protect your brain This could mean deadlifts and squats in the gym, 10 press-ups at the end of a run or even carrying bags of heavy shopping – just make sure your muscles are moving against resistance at some point each day. Researchers from Rush University Alzheimer’s Disease Center followed 900 people in a Chicago retirement community over four years. They found that those with greater muscle strength were significantly less likely to experience cognitive decline.

Eat Greek The Mediterranean diet has been consistently linked to a lowered risk of everything from coronary heart disease to numerous types of cancer. Recently, it has also been used to treat people with depression. “In one Australian study, a dietician encouraged people to eat Mediterranean-style,” explains Dr Brendon Stubbs, a clinical lecturer at the Institute of Psychiatry at King’s College London. “Half of the 67 participants switched to this diet, alongside their regular treatment [of psychotherapy, antidepressants or both] while the other half continued with their normal diet and antidepressant treatment. At the end of 12 weeks, those who’d switched their diets had a bigger reduction in depression symptoms.”

The experts’ guide to… boosting your body

Be kind to yourself Helen West is one of the dieticians behind The Rooted Project, a website that aims to dispel myths around food and nutrition. She recommends focusing on the positive steps taken, and not on the things we want to change. “Weight is not a behaviour – so it’s counterproductive to focus on it. Focus on actionable things, like eating more fruits and vegetables, finding a way to sneak more movement into your days, and trying to get more sleep.”

Try HIIT As we get older, our cells’ ability to create energy declines. However, a study by doctors at the Mayo Clinic (a US-based medical centre) involving 72 participants across two age groups, found that high-intensity interval training (HIIT) not only halted but reversed this trend, boosting cells’ ability to generate energy by 69% in those between 65 and 80 years of age, and by 49% in younger individuals (18-30 years). You could start by alternating three minutes of fast walking and three minutes of slow walking for 30 minutes or more, four times a week.

Make time for recovery If you do decide to start a new, intensive gym regime, remember the importance of recovery. “Overtraining can cause inflammation, which has been linked to everything from cancer to depression,” says The Foundry’s Dave Thomas. He advises wearing a tracker such as a Fitbit when you sleep, to work out your average resting heart rate. “If, the morning after you’ve trained, your resting heart rate is noticeably above normal – by 10-15bpm or more – it means you haven’t yet recovered and shouldn’t train that day.”

Move like a centenarian Turns out, though, that the secret to long life might not be down to how much you exercise, but to how much you move. In his study of what he called the world’s Blue Zones (areas such as Ikaria in Greece where inhabitants regularly live past 100), writer Dan Buettner found that those who were healthiest in old age “live in environments that nudge them into moving every 20 minutes or so”. Walking, gardening or even just getting up at regular intervals were enough to keep Blue Zone-dwellers healthy throughout their lives. According to researchers at Maastricht University in the Netherlands, low- to moderate-intensity movement spread throughout the day is associated with significantly improved insulin levels, compared with doing just an hour of intense exercise.

Hack your circadian rhythm “There are some fairly basic steps you can take to make sure that you’re not delaying the production of melatonin – the hormone that makes us sleep,” says Dr Mithu Storoni, author of Stress Proof. “Having a big breakfast and an early, light dinner can help you sleep better, because food and digestion delays the onset of melatonin.” Equally, exercising in the morning rather than the evening, and making sure that your bedroom is between 18 and 21C will mean you’re more likely to drift off – warmer temperatures may disrupt our ability to fall into an REM sleep.

Cut down your eating hours Restricting meals to an eight-hour period (and having 16 hours of “fasting”) will help lower insulin levels and cause your body to start burning its fat stores. “This whole process is excellent news for brain health,” explains dementia specialist Dr Jamie Wilson. “Reducing insulin levels can have an impact on your generation of amyloid beta, one of the harmful proteins that have been linked to Alzheimer’s. 10am to 6pm are the usual hours, but it’s flexible.”

Add ferments to every meal A healthy and diverse microbiome (the ecosystem of bacteria in our intestinal tract) is thought to improve our immune system and guard against everything from heart disease to depression. “Adding probiotic foods such as natural yoghurt, sauerkraut, kimchi, kefir and miso to every meal has been shown to increase the diversity of our gut bacteria,” says Storoni. “And, according to a meta-analysis of data published last year, this not only helps with general wellbeing, but also reduces feelings of anxiety.”

The experts’ guide to… nourishing your soul

Experience something awesome In his studies into the impact of psychedelics on patients with depression, Dr Robin Carhart-Harris of Imperial College London noticed an interesting phenomenon. “After the treatment, people became more appreciative of nature and reported feeling more ‘connected’. They no longer felt isolated.” If half a tab of acid all seems a little too 1969, Carhart-Harris argues that just experiencing awe could have a similar effect – “by challenging our self-involved viewpoints and giving us a sense of perspective on our problems”. One way to do this is to write the story of a time you felt in awe of nature – according to a study at Stanford University Graduate School of Business, this quick task increased participants’ sense of wellbeing, as well as their willingness to give to charity; it even made them feel like they had fewer time pressures. The key is to understand yourself as a small part of a vast, living system – for that, nothing beats being outside in nature. A day trip to a forest, or an evening gazing at the vast night sky at a local observatory may be more effective than an indoor writing task.

Be grateful The words “gratitude journal” may make you cringe, but regularly writing a list of things you’re grateful for has, in one randomised control trial , been shown to foster a deep and lasting sense of contentment. “The act of writing with a pen seems to be important,” says Dr Aria. “But this weekly 20-minute task saw participants’ moods improve.” In fact, eliciting the emotion of gratitude, even just once a week, led to a 28% reduction in perceived stress. Each entry should be specific – “I’m grateful that my partner brought me tea in bed this morning,” rather than “I’m grateful for my partner” – and you should reflect on what it was about that moment that made you feel particularly good. During the task, participants reported falling asleep more easily and sleeping, on average, for 30 minutes longer each night.

Join a tennis club According to a study of more than 800 people (who were followed for the first six years after they retired by researchers at the University of Queensland), being a member of a club (of any kind) is associated with an increase in reported quality of life. Another study, by US researchers, who followed more than 8,000 people in Denmark for a period of 25 years, found that being a member of a tennis club was particularly beneficial; it conferred almost an extra 10 years of life, compared with people who did not exercise (in comparison, indoor exercises like running on a treadmill conferred only one and a half extra years). The difference, the researchers theorised, was the element of “play”.

Find your meaning A sense of purpose, a passion or a thing, person or place that gives our life meaning has been shown to help guard against a number of health conditions. One wide-ranging Japanese study followed 3,000 people for an average of 13 years and found that men who reported having a greater sense of purpose were significantly less likely to die of a stroke or cardiovascular disease. One study asked participants to spend a week taking photographs of all the most meaningful things, places and people in their lives. At the end of the week, they compiled all the photographs, and reflected on them. The result was that each participant had a stronger idea of their life’s purpose and reported a greater feeling of meaning and contentment.

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