Three minutes all out do more than ninety minutes at a steady pace

I am forever prodding at things to see whether they could work better. Once I started paying proper attention to my energy and to actually feeling good, plenty in my life shifted, and my training shifted with it. For years I was a runner. These days I cycle, partly because my joints much prefer it, and partly because someone gave me a mountain bike in orange and turquoise, retro as anything, exactly my colours. I get home, spot it standing there, and I am already looking forward to the next ride.

Running was the same story. Bright turquoise trainers, and every time they catch my eye I want to be out in them. My inner child, it turns out, can be bribed with my favourite colours. Silly? Probably. It works, which is the part I care about. Is purple your favourite colour? Then go and get yourself that cool purple bike! Nothing wrong with keeping your inner child happy with something that is good for the pair of you.

And I used to love wrecking myself. Being completely empty afterwards, knowing my body gave the lot, was a feeling I was rather fond of. Since the menopause I have known that heaping more stress on top is not clever, so I train differently now, and I went looking for something that gives plenty back without swallowing half my day.

Which is when I came across a study that had asked more or less that question. One group rode steadily for 90 minutes. The other went flat out for 3 minutes in total. Afterwards, the blood of that second group looked nothing like the blood of the first.

What they did, and what came out

At Rockefeller University in New York, Paul Cohen’s lab set the two kinds of effort against each other. One group did 6 sprints of 30 seconds, everything they had, 4 minutes of rest in between. The other rode for 90 minutes at a pace they could hold comfortably. Blood was drawn before and after, and the team looked at what had moved in it: proteins, metabolites, all the messages cells send one another.

Straight after the sprints, close to 25% of every protein measured had changed. After the 90-minute ride it was under 0.25%. More than 200 metabolites shifted on the sprint side as well.

The researchers then held those proteins up against data from more than 53,000 people in the UK Biobank, a large British health database. Of 33 proteins linked there with lower cardiovascular and metabolic risk, 32 moved after sprinting and 3 after the steady ride (Olsen et al., Cell Reports Medicine, 2026).

What those substances do

Muscles are not just engines. While you work, they release substances into the blood that talk to the rest of you: liver, fat tissue, blood vessels, brain. Exerkines, they are called, and the traffic between organs is what the researchers were watching.

So during those 4 minutes of rest, your body holds a brief meeting with itself. Unlike most meetings, this one produces something on the spot.

The new part from this study: that conversation keys on how hard you go, far more than on how long. 90 minutes is a perfectly good way to spend your time, just not if this particular signal is what you want.

So what about your steady ride?

Worth exactly what it was worth yesterday. Steady endurance work does things sprinting cannot, and the sprinters in this study were no healthier than anyone else: what got measured was the short window after exercise, in healthy, active people. Where that leaves you in 5 years is not in the paper. The Biobank comparison shows those proteins travel with lower risk, and travelling together is not the same as causing.

Where it turns practical: when time is short, this is the shape that moves the most per minute of effort.

Honestly? It is easier than it sounds

I have done the session a handful of times now, and I do understand that “flat out” sounds alarming. 30 seconds is nothing, though. You go, you count, and then you are allowed to potter again. 6 times, 4 minutes apart, spinning or jogging gently in between to get your breath back. The rest of the half hour is warming up and winding down. Almost anyone can do this, and it is properly good fun: 30 seconds is short enough to throw everything at it.

What the session looks like

10 minutes of warming up, finishing with 2 10-second bursts so your legs know what is coming. Then 6 sprints of 30 seconds, 4 minutes apart, and in those 4 minutes you keep moving gently rather than stopping dead. 5 minutes of cooling down to finish.

Those 4 minutes feel generous, and they are meant to. Only with proper recovery can you go flat out again on the next one, and flat out is the whole point. Shorten the rest and you have built yourself a hard endurance session with a different effect.

Come along

I recorded the session with music underneath that moves as you do: easy through the warm-up, sharp the moment you have to go. I tell you when to start, count you into every sprint and give you a shout with 5 seconds left. Nothing else to keep track of.

How to build up

The protocol from the study is where you are heading, not where you start. Begin with 3 sprints of 20 seconds at around 90%, same 4 minutes of rest. If that sits well after a week or two, make it 4 sprints of 30 seconds. The 6 from the study come after that. Each step comes when you genuinely feel recovered inside those 4 minutes.

And do not skip the warm-up. Without those 10 minutes the first sprint is a cold start, and it feels twice as hard.

Cycling or running outdoors? Check your route first

Indoors, on a bike or a treadmill, this is easiest: all you do is move and listen. Outside, work out in advance where the sprints will land. You do not want to be 30 seconds into one as a set of lights, a junction or a stretch full of people comes up. Find a long, quiet run with no traffic and put your sprints there.

Traffic comes first, always. If a junction is coming or someone is heading your way, wave that sprint off and take the next one. There is another along in a minute, and failing that, next week.

When to check first

Going flat out sends your blood pressure up sharply for a short while. If you are on medication, have a heart condition or are pregnant, speak to your doctor first. That is not caution for form’s sake: 30 seconds at full tilt is a different animal from an hour of steady riding.