Reebok I Run 4.0 Treadmill Review: Worth Buying?

If you're looking for a new home treadmill, the Reebok I Run 4.0 is a compact, foldable machine built from the ground up with home running in mind. It aims to strike a balance between gym-style features, sturdy build quality and affordability, while staying small enough to store away when it's not in use.

We bought the I Run 4.0 and tested it thoroughly over 8 weeks, putting every feature through its paces and pushing it to its limits to see how it holds up. So, is it any good?

First impressions and setup

Out of the box, the I Run 4.0 is a little smaller and lighter than most of Reebok's other treadmills, at around 56kg. It still takes two people to lift, so make sure you have an extra pair of hands ready on delivery day.

Setup is quick and easy. It took us roughly 10 minutes from unboxing to starting our first run, with no assembly required: just unpack, unfold and you're good to go. Despite being lighter than some other Reebok treadmills, it never felt cheap or flimsy during testing.

Running belt and cushioning

The running deck is one of the most important features of any treadmill, and the I Run 4.0 does a decent job. It's fairly wide, with similar dimensions to other treadmills in this price range (L125cm x W46cm).

The Elastomer cushioning technology works well underfoot, providing a comfortable, shock-absorbing surface. Many budget treadmills leave your feet fatigued from a lack of cushioning. The I Run 4.0 doesn't have this issue. After 60+ minutes of running, we felt fresh and able to keep going.

Display

The 4-window LED display is bright and modern, built into the front of the machine just below the tablet holder. It feeds back on speed, distance, time, calories, pulse, body fat and your total step count.

The body fat guide is a nice touch. It uses the integrated hand sensors along with your gender, age, height and weight to estimate your BMI. BMI isn't a perfect measure of fitness, but it's handy for tracking rough progress on your fitness journey.

The most notable drawback is the lack of Bluetooth. At this price, we'd expect every treadmill to connect to your phone so you can track runs in a fitness app. It's a shame the I Run 4.0 misses this, though if you're not bothered about app tracking you won't even notice. Otherwise, the display covers all the metrics you'd want while running.

Speed and incline

The I Run 4.0 has a maximum speed of 16 km/h (approx. 10 mph), powered by a 1.25 HP motor. It feels smooth and runs almost silently, so you won't wake the family or neighbours during early-morning workouts.

There's no adjustable incline, which is a shame, but it does have a fixed 4-degree incline. It's barely noticeable, though a slight incline while walking and running has been shown to be better for joint health.

Speed is adjusted using the buttons below the display. We'd have liked integrated handlebar controls at this price, but Reebok seems to have opted for a sleeker, simpler design here. It's not a dealbreaker, just worth noting.

Programmes

This is where the I Run 4.0 really comes into its own. The 12 programmes are easy to access and cover a range of walking and running sessions to suit all abilities, from the gentlest stroll to the most gruelling run.

On top of the 12 presets, you get a choice of 3 target workouts focused on time, distance or calories burned. We loved this feature, and often found ourselves pushing to hit a calorie target before ending a session.

Build quality

As with every treadmill we review, we put the build quality to the test. Plenty of training programmes are all well and good, but you want a machine that's going to last.

Straight out of the box, the frame felt solid and strong for the price. We were impressed by how light the 4.0 is compared with other treadmills in this bracket. It's still heavy, just not quite as heavy as some rivals, and it folds and unfolds smoothly without any hassle. In use, the machine stays sturdy without rocking, moving or rattling, and runs with very little noise thanks to the cushioned deck.

Warranty

Reebok always provides great warranties, and this treadmill is no different. It comes with a 10-year motor warranty as standard, so you're covered if anything goes wrong with the motor through no fault of your own. You also get a 2-year parts and labour warranty.

How it compares

For a similar price, you can pick up the Reebok Jet 100 Treadmill, which we've also tested. It has more features than the I Run 4.0 and a larger running surface. The one important difference is the maximum user weight (120kg on the I Run 4.0 versus 110kg on the Jet 100).