We’ve all heard it many times before – to get healthier, you need to do 30 minutes of strenuous exercise at least five times a week.

I know, maddening if you feel this is beyond you: I see patients’ frustration with this advice all the time in A&E.

They come in with problems largely caused by inactivity – such as diabetic complications, back pain, heart attacks and strokes – and have been told to exercise this amount, yet many feel it’s an impossible ask.

I repeatedly hear phrases such as ‘I can’t manage half an hour – not with my knees/back/heart or at my age, so what’s the point?’

But they don’t need to do as much as they think to make a difference.

For even short walks can be a game-changer – and the evidence for that is now overwhelming.

You may not see or feel it, but one of the most important changes is the way these short bursts of activity increase your insulin sensitivity – your body’s ability to use insulin to keep your blood sugar under control.

Basically, the better your insulin works, the lower your risk of developing type 2 diabetes, obesity, heart disease and so on.

Small strolls – the faster the better – to the shops, up and down the stairs, even a loop around the kitchen while the kettle boils, aren’t trivial – they’re life-extending, writes Dr Rob Galloway

Even small amounts of walking to break up prolonged sitting is one of the most healthy activities you can do

The science is clear, and it’s high time we started shouting about it – rather than criticising patients for not being able to complete the recommended exercise guidance.

In one of the most striking new studies on this, researchers from the Department of Exercise and Sports Sciences at Manipal College of Health Professions in India put 28 healthy young adults through two experiments: they were asked to sit for two hours after lunch (a set-up that probably sounds familiar to anyone with a desk job).

However, on one day they simply sat during their two-hour break; on another, they were asked to climb two flights of stairs for two minutes every half an hour. That’s it.

And yet this tiny adjustment produced a big impact: those who did the short bits of exercise had significantly lower post-meal blood sugar levels compared to when they did no exercise, reported the journal Nature Scientific Reports.

Why does that matter? Because after we eat, blood sugar rises and if that sugar isn’t quickly absorbed and used, it lingers in the bloodstream, causing inflammation, damaging blood vessels, and leading to a rise in insulin levels – which piles on the weight.

Over time, this contributes to type 2 diabetes, stroke and even dementia.

Flattening those blood sugar spikes isn’t just about better numbers on a lab printout – it’s about protecting our organs so they function in an optimal way.

This new research confirms what many of us suspected for years – that even small amounts of walking to break up prolonged sitting is one of the most healthy activities you can do.

One of the earliest and most powerful insights on this came from a study of double-decker bus drivers and conductors in the 1950s. Researchers compared the health of the drivers, who sat for most of the day, with the ticket collectors, who climbed up and down the stairs checking fares.

The results were striking: the active conductors had far lower rates of heart attacks and strokes than the sedentary counterparts.

At the time, no one quite understood why – after all, they were just walking. But we now know that the benefits were from improving blood sugar control.

We’ve all been conditioned to believe that unless you’re sweating and out of breath, exercise isn’t helpful. But that’s not what the latest evidence shows.

Even more remarkably, these short bursts of exercise can do more for your metabolic health – everything from how well your body controls blood sugar, to how it processes fat, and even your risk of diabetes – than longer, more traditional workouts.

This was proven in a study by Zhejiang University in China, published last year in the Scandinavian Journal of Medicine & Science in Sports.

Overweight office workers were put through two regimens: one day they stayed seated except for a single 30-minute walk, mid-shift. On the other day, they went for a brisk three-minute stroll – ten in total – every 45 minutes.

Meals, time spent in their chair and time walking were identical – the only difference was when they did the exercise.

And guess what: after doing the 30-minute walk, the participants’ blood sugar levels were about 1mmol/L lower than those who did no exercise.

This doesn’t sound much, but will significantly improve your metabolic health and reduce your risk of most conditions, from cancer to Alzheimer’s.

But what was remarkable was that those who did the ten, three-minute walks had an even greater drop in average blood sugar levels – an additional 1.3mmol/L on top of the 1mmol/L.

Sensors placed on their muscles showed why: even though the overall exercise time was the same, because the muscle fibres still contract for a while after stopping exercise, the muscles were spending longer periods of time literally sucking glucose out of the blood to feed them.

The evidence that even a small amount of walking can make a big difference was proven beyond doubt in a landmark study in 2023, where researchers at the University of Cambridge reviewed nearly 200 of the largest and best studies, monitoring more than 30 million adults, to answer a simple question: how little exercise can you do to see a benefit?

The results were compelling: compared to people who stayed glued to their sofas and desks, just 11 minutes a day of brisk walking was enough to cut the risk of dying over a ten to 15-year period by 23 per cent.

It also lowered the risk of developing heart disease by 17 per cent and cancer by 7 per cent.

The takeaway? While more activity brought more benefit, the biggest jump comes from doing something rather than nothing. It is true, however, that the faster you walk, the better, as numerous studies have shown – not just for your fitness, but for your brain.

As part of the UK Biobank project (a huge database of British participants’ health information and samples), a study published earlier this year, where people were asked how fast they usually walked, found that those who walked at a steady to brisk pace (above 3mph) were about half as likely to develop dementia as those who walked more slowly.

Brain scans revealed that brisk walkers had larger, healthier hippocampi (the part of the brain involved in memory) and less white matter damage, meaning their brains were ageing better.

Walking can also help prevent musculoskeletal pain – something which might seem counterintuitive.

However, people who walked the most were 23 per cent less likely to develop chronic lower back pain than those who walked the least, according to a study published in JAMA Network Open last month.

The research monitored more than 11,000 adults (who all started out without back pain) for more than four years.

Crucially, the back-protecting benefit came from the total amount of walking, not how fast or intense it was.

All these studies show that while more activity brings more benefit, the greatest comes from doing a small amount of walking as often as you can rather than doing nothing.

In other words, it’s not about marathons, expensive gyms or Lycra. Small strolls – the faster the better – to the shops, up and down the stairs, even a loop around the kitchen while the kettle boils, aren’t trivial. They’re life-extending.

@drrobgalloway

Avoid exercising near bed time 

If you do a high-intensity workout within four hours of going to bed, you’re more likely to struggle getting to sleep, get less of it and not recover as well, according to a new study by Monash University in Australia, published in the journal Nature Communications.

But shift that same session earlier – or just make it a gentler one in the evening – and those problems disappear.

We’ve now got a clear answer why, thanks to data from this study, where nearly 15,000 people used a wearable tracker (called WHOOP). It showed that when people did intense exercise late in the day, their resting heart rate stayed higher through the night, their heart rate variability – a key sign of recovery – dropped, and their core temperature stayed elevated, even into sleep.

In other words, their bodies just didn’t wind down properly. And that disruption made it so much harder to fall asleep and stay asleep.

All this matters because poor sleep messes with your ability to control blood sugar the next day, which could undermine one of the main reasons you exercised in the first place – maintaining a healthy weight.

So, doing something is almost always better than nothing – but timing matters, too.