Is HIIT (High Intensity Interval Training) the best for fat loss?

HIIT can be a very effective tool for fat loss.

But it can also be the downfall for some.

Like most things…

It depends.

On paper, HIIT looks great.

You can burn a lot of energy in a short amount of time. It also has an effect on what’s called EPOC (excess post-exercise oxygen consumption) or, in simple terms, the “afterburn” effect.

Heart rate spikes. Lactate builds. Blood pressure rises. A number of systems in the body are pushed hard, and it takes time (and energy) to bring everything back down to baseline.

That process costs energy.

And yes – some of that energy will come from fat.

There are even studies showing significantly greater fat loss from HIIT compared to steady-state training.

Sounds like a no-brainer, right?

Not quite.

Because here’s the catch…

Too much of a good thing becomes a bad thing.

HIIT is very demanding. It places a big stress on the body.

This isn’t something you want to be doing every day.

For most people, once a week is plenty. Maybe two to three shorter sessions spread across the week if recovery is good.

But beyond that?

You’re likely digging a hole you can’t recover from.

And that’s the real key here:

You can only train as hard as you can recover.

This is where context matters.

In your 20s, with low stress, plenty of sleep, and minimal responsibilities, you can get away with a lot more.

Fast forward a few years…

Kids. Work. Bills. Broken sleep.

Now the same HIIT session hits very differently.

It takes longer to recover. It drains more from the system.

If your sleep is poor, your stress is high, or you’re already feeling run down, adding more high-intensity work is often the worst thing you can do.

The same goes for anyone navigating big hormonal shifts, where recovery is already compromised.

At that point, HIIT stops being helpful… and starts becoming another stressor.

And that’s not what we want.

Because ultimately, training should leave you feeling better.

More energised. More capable. More resilient.

Not flat. Not exhausted. Not dreading the next session.

So is HIIT the best for fat loss?

Sometimes. – But not always.

Used sparingly, it can be a powerful tool. Overused, it can hold you back.

Like everything else – it’s about using the right tool, at the right time, for the right person.