Is sitting the new smoking? What all that sitting does to your lower back, and how to fight back
By Nathan Jandrell, owner of Full Range Fitness · 28 October 2026
Most of us sit far more than we realise: at a desk, in the car, on the sofa, at the table. You may have heard the phrase "sitting is the new smoking". It is a headline, not a scientific finding, and sitting is not as dangerous as smoking. But the research behind it is real, and it matters for your health and especially for your lower back. This post explains what the evidence says, why long days of sitting can leave your back feeling tight and fragile, and what we see happen when people start building strength with us in Polegate, near Eastbourne and Hailsham.
What the research says about sitting
Large studies have followed hundreds of thousands of people for years. They consistently find that people who spend the most time sitting have a higher risk of early death and of conditions such as heart disease and type 2 diabetes, even after taking other factors into account. A major analysis of more than a million people, published in The Lancet in 2016, found that sitting for more than about eight hours a day was linked to a higher risk of dying early.
That same study had a hopeful finding too. People who did around 60 to 75 minutes of moderate activity a day did not show that extra risk, however much they sat. The UK Chief Medical Officers' guidelines say the same in plain terms: be active, and break up long periods of sitting with movement whenever you can.
So the message is not "never sit down". It is: sitting all day and not moving much is the problem, and regular activity is the antidote.
Use it or lose it: what sitting does to your muscles
Your body adapts to what you ask of it. Muscles that are worked regularly stay strong; muscles that are rarely asked to do much gradually lose strength. When most of your day is spent sitting, some muscles hardly have to work at all:
- Your glutes and hamstrings, which do much of the work when you stand up, climb stairs, lift or carry, spend hours switched off underneath you.
- Your trunk muscles, the "core" muscles around your middle that help you control your spine when you bend, twist and lift, have little to do when a chair is holding you up.
- Your upper back gets little work when your arms are forward at a keyboard or steering wheel.
At the same time, many people who sit a lot feel stiff through the front of the hips and thighs, the chest and the shoulders, because those areas spend so long in one shortened position. You might notice it as tight hips when you stand up after a long drive, or a back that feels stiff and "locked" first thing in the morning.
It is worth being clear about one thing. You may have read that tight or weak muscles pull your spine or pelvis "out of alignment" and that this causes back pain. The research does not show that small differences in posture or muscle balance are the main cause of back pain. What does seem to matter is capacity: how much your body is ready to handle. Hours of sitting reduce that capacity. Your back is not damaged; it is simply less prepared for the moment you ask it to do something it is not used to.
Why that leaves your lower back vulnerable
Low back pain is the leading cause of disability worldwide. For most people it is not caused by anything serious, and scans often show changes that are common in people with no pain at all. Pain often flares up when what you suddenly ask your back to do is more than it is currently used to: lifting a heavy box, bending to pick something up off the floor in a hurry, a long day of gardening, or twisting awkwardly.
When the legs, hips and trunk are strong, they share the load and your back has plenty in reserve. When they have spent years doing very little, there is less to share the load, and everyday moments are more likely to tip your back over the edge.
What we see at Full Range Fitness
We regularly meet people who come to us with a lower back that feels tight, fragile or painful, often after years of desk work and driving. Many are nervous about exercise because they are worried about making it worse.
What we usually see is that within a few weeks of coached training, people feel a real difference. Their back feels less stiff, everyday tasks feel easier, and they trust their body more. We do that by gradually strengthening the muscles that sitting has let go, especially the glutes, hamstrings, upper back and trunk, and by easing off stiff areas with mobility work, all at a level that suits them on the day.
That fits the research. NICE, which sets treatment standards in the NHS, recommends exercise as a core part of managing low back pain, and a large review in JAMA Internal Medicine found that exercise, especially combined with learning about your back, lowered the risk of having another episode of low back pain.
Do members still hurt their backs?
Sometimes, yes. Backs are part of being human, and nobody is completely immune. But it is very rare for a member to hurt their back in a session. Every session is fully coached, so a coach is watching how you move, choosing the right weight and adjusting exercises for you.
When members do tweak their back, it is almost always outside the gym: bending quickly to pick something up off the floor, lifting something awkward, or a sudden twist. What we notice is how quickly they bounce back. Because their muscles are stronger and better conditioned, a flare-up that might once have put them out for weeks is often settled in days.
We have several members who had struggled with their lower back for many years before they joined us. Their backs still flare up now and again, but much less often, and when it does happen, it is a few days of taking it easy rather than weeks of being stuck. That is what building capacity looks like in real life. Everyone is different, and we can't promise the same result for everyone, but it is a pattern we see again and again.
Simple things you can start today
- Break up your sitting. Stand up and move for a minute or two every 30 to 60 minutes. Walk while you take a phone call; take the stairs.
- Move every day. Aim for the UK guideline of at least 150 minutes of moderate activity a week, and some muscle-strengthening work on at least two days.
- Wake up your glutes. Glute bridges: lie on your back with knees bent, squeeze your bottom and lift your hips, hold for two seconds, lower slowly. Ten to fifteen, a couple of times a day.
- Open the front of your hips. A gentle kneeling hip flexor stretch, 30 seconds each side, especially after a long drive.
- Practise picking things up. Bend at your hips and knees, keep the object close and stand up through your legs. It is a skill, and like any skill it gets better with practice.
Some discomfort while you move is usually fine; sharp pain, or pain that is clearly worse the next day, is a sign to ease off. Our guide Back pain and the gym goes into this in more detail, including the warning signs that mean you should see a doctor first.
We are coaches, not doctors or dietitians, so speak to your GP if you're unsure, and get urgent medical help if your back pain comes with numbness around your genitals or bottom, problems controlling your bladder or bowels, a high temperature, or pain after a serious fall.
Start with the 28-Day Kickstart
If your back has been holding you back, our 28-Day Kickstart is the easiest way to start. It begins with an intro session, then gives you 28 days of unlimited coached small group personal training, nutrition guidance and a body composition scan, all for £149. Every session is one hour and fully coached, so tell your coach about your back and they will adapt the exercises for you.
If you would like a gentler start, try Vitality, our slower-paced, controlled strength session, or Mobility. Over 50s can try Legends.
We are on the Chaucer Business Park in Polegate with free parking, about six minutes from Hailsham and around twelve minutes from Eastbourne. Message us on WhatsApp on 07925 149477 if you would like a chat about where to start.
Sources
- Ekelund U, et al. Does physical activity attenuate, or even eliminate, the detrimental association of sitting time with mortality? A harmonised meta-analysis of data from more than 1 million men and women. The Lancet 2016.
- Biswas A, et al. Sedentary time and its association with risk for disease incidence, mortality, and hospitalization in adults: a systematic review and meta-analysis. Annals of Internal Medicine 2015.
- UK Chief Medical Officers' Physical Activity Guidelines, 2019.
- Hartvigsen J, et al. What low back pain is and why we need to pay attention. The Lancet 2018 (Low Back Pain Series).
- NICE. Low back pain and sciatica in over 16s: assessment and management (NG59), 2016, updated 2020.
- Steffens D, et al. Prevention of low back pain: a systematic review and meta-analysis. JAMA Internal Medicine 2016.
- NHS. Back pain. nhs.uk