It's one of the questions we hear most, usually from someone who has been pounding the pavements for months without much change: is HIIT better than running for losing fat? The honest answer on HIIT vs running for fat loss is that both can work, but they work in different ways. For most busy Londoners, HIIT has a few practical advantages.

One thing first. Fat loss comes down to energy balance over weeks and months, which means food matters as much as training. We've written more about that in calories and weight loss. What exercise does is help you burn more energy, hold on to muscle and stay consistent, and that's where the choice between HIIT and running makes a difference.

HIIT vs running for fat loss: how each burns calories

Steady running is predictable. You hold a pace for a set time or distance, and the calories you burn depend mostly on your body weight, speed and how long you're out. It's simple and it works, but your body adapts, so the same 5k route gets easier and slowly does less for you.

HIIT stands for High Intensity Interval Training: short bursts of maximum effort followed by short recovery periods. In our 45-minute classes, members can burn up to 1,000 calories, though the real figure depends on your size, fitness and how hard you push. Harder work also creates an afterburn effect, where your body keeps using extra energy while it recovers. It's a nice bonus, but the session itself does most of the work.

Why HIIT often has the edge

The biggest advantage is time. You get a hard, full-body session in 45 minutes, which is easier to fit around a London working week than a long run. The second is muscle. Running on its own does little for upper-body strength, while HIIT combines cardio with strength work. Our HIIT Strength class, for example, uses barbells and racks for heavy compound movements. More muscle helps you look leaner at the same weight and supports your metabolism.

The third is variety. With Circuits, Energy, Strength, TRX and Ass N Abs on the timetable, the workouts are always different, and that keeps people coming back. Our members' 6-week results show what consistency can do: Aneta lost 3.5kg and 4cm from her waist, and Hasan lost 3.7kg and 7cm.

Where running still wins

Running is free, you can do it anywhere and there's something to be said for clearing your head outdoors. It builds a strong aerobic base, and if you're training for a 10k or a half marathon, you need to run. Where people go wrong is running hard every day. That wears down joints and motivation. Easy running, a couple of times a week, pairs very well with HIIT.

The best approach: combine them

Our FAQ mentions the 80/20 rule: around 80% of your training at moderate intensity and 20% at high intensity. In real life, that could mean two or three HIIT classes a week plus an easy run or a long walk at the weekend. The NHS physical activity guidelines recommend 150 minutes of moderate activity or 75 minutes of vigorous activity each week, plus strength work on two days, and a mix like this covers all of it.

Don't do maximum-effort sessions every day. Recovery is when you adapt, and our coaches explain why in is HIIT safe every day? If you like the idea of running and functional training together, our Hyrox training classes are worth a look too.

Want to see what HIIT does for you? The 2-week HIIT Kickstart gives you four coach-led classes and a goal-setting consultation for £39. Questions first? Get in touch and we'll help you plan it.