There will be thousands of runners lined up at the start line on Sydney’s Harbour Bridge on Sunday to race in the annual Sydney Marathon.

And for those preparing to take the 42km race around the famous city seriously, a waist belt will be their number one accessory.

Amazon’s Sport2People running belt is discounted for a limited time only to just $12.66, with its design heralded by customers as the ultimate in support for long-distance running and fitness classes.

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The running belt won’t move, bounce or rub on your skin as you run and it can fit everything from your phone to cards, car keys and even an energy bar to fuel you on the journey.

It’s expandable so can be made to fit both men and women and features a water-resistant pocket to keep your items dry in any weather condition.

The two reflective strips down either side of the belt help to keep joggers seen even in low light conditions.

There are a multitude of reasons one might wear the belt, even after the marathon is completed. It’s perfect for travel and even at large music festivals.

There are more than 680 reviews on the running belt, with 72 per cent of those five stars.

“It’s not bulky. Slim. Can confirm you can put in an iPhone 11. I use it when I go for a bicycle ride. I also found other uses like when I’m mowing the lawn,” said one customer.

“This sports belt is ultra lightweight, adjustable and easy to fit. Two separate zipper pockets fit my car keys and mobile phone. Little opening allows for earbuds lead. Good quality and competitive price. You know something is great when you keep using it,” said another.

A third person added: “Very convenient. As advertised. Fits in the cell phone, keys and cards very easily. Hassle free runs”.

You can read more about the running belt, and even choose a different colour, on the website here.