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Last Updated: July 7, 2021
Who It’s For: Conditioned athletes looking to enhance their performance and running form on an affordable curved treadmill
- Powder coated steel frame and uprights
- This is a sturdy machine. However, unlike other manual treads that tip the scales at close to 400lbs, the AirRunner only weighs 280lbs, so it is comparatively light
- Wheels on front of track and leveling feet at the base
- When you need to move it, the wheels allow it to be gently rolled. Leveling feet on the rear base make it so it won’t rock on your floor.
- Large steel beam at base of track allows machine to be tipped and rolled
- This enables users to move the AirRunner safely, without grabbing the side of the frame or the slats
- Horizontal handlebar supports LCD console
- Handlebars allow for safely getting on and off the AirRunner. A horizontal bar spans the front end and supports the console
- Console is simple and easy to use, powered by four AA batteries
- You do not need to plug in the AirRunner. It is manually powered and only requires a few batteries to run the console
- Slat belt has no max speed, it will go as fast as you do
- This belt is designed to last up to 150,000 miles. There is no max speed as the belt moves underfoot to match your pace. Want to go faster? Speed up. Want to slow down? You’re in charge.
- Running surface is 17” wide and 62” long
- While this is a little narrow, the 62” length provides room for plenty of forward stride and kickback space.
- Powder coated steel frame
- Shock-absorbing slat belt
- Running surface is 17.1” wide and 62.2” long
- Step-Up Height: 13.45” high
- Treadmill weight: 280lbs
- Footprint: 70” L x 32” W x 64” H
- Max user weight: 350lb
- LCD Console with both Bluetooth and ANT+
- Console powered by 4 AA batteries (not included)
- Console displays Time, Calories, Distance, Speed, Watts, Pace & Heart Rate
- Comes preloaded with Interval programs, Target programs and Heart Rate programs
- Function keys include Bluetooth and ANT+ connect
- Split time key
- Speakers on/off
- There are also start/stop keys
- Rest/Work indicator lights for interval programs
- Manual belt
- Does not require electricity
- Belt is rather narrow at just 17.1”
- There is no max speed, the belt will go as fast as you do
- Upright handles for balance while running
- Curved belt supports proper running form
- 5-year warranty on Frame
- 3-year warranty on On-Wear Parts
- 1-year warranty on Labor
In-depth Review of Assault Fitness AirRunner Manual Treadmill
The Assault AirRunner has a steel frame with powder-coated uprights. Rubberized slats combine to create the slat belt which sits on 100 low-friction ball bearings that line the surface of the deck. The bearings allow the slat belt to move smoothly over the surface of the curved frame. The frame is sturdy with adjustable leveling feet on the base to ensure it sits level on your floor. There are two wheels on the front of the deck and a steel handlebar at the base of the deck allows you to lift the AirRunner and roll as needed. This is a comparatively light machine, it weighs 280lbs — which sounds monstrous, but compared to other manual treads it’s not bad. It will support up to 350lbs, so it is still a solid manual treadmill.
- Construction: The frame is sturdy with black powder coated sides and uprights. It does require some minor assembly. The deck comes preconstructed, you just need to attach the uprights and front handlebar (with console). We love that Assault Fitness has made this a one-person job! The uprights are pre drilled and notched, so you can set the upright into the notch on the side of the frame and it will sit there (semi-secure) while you attach the other side. This makes it so you don’t have to have one person hold the upright while another one screws it into the frame. The pre drilled holes and notched system is very handy. The uprights and handlebars are sturdy, but not super heavy, so again this is very manageable by one person.
- Cushioning/Feel: The cushioning in a slat belt treadmill is in the slats themselves. While the rubberized slat components do absorb a bit of impact shock, we noticed less cushioning on the AirRunner than on more expensive machines. This could be because the slats are narrower (only 17.1” wide), so there’s less surface area to absorb shock, but cushioning is not the signature feature on the AirRunner.
- Length/Width: The AirRunner running belt is 17.1” wide and 62.2” long. You have plenty of forward stride and kickback length, but the width is a little narrow. If you are a large runner with a wide foot span, the AirRunner may not provide enough room side to side. While running, if you hit your foot on one of the side rails as opposed to the slat belt, it can be dangerous.
- Indoor Training Value: One huge benefit of the AirRunner is the ability to train indoors all year round. Since the AirRunner closely mimics running outdoors, it is a great training option for runners who want to stay conditioned through the off-season.
- Many treadmills provide a smooth run, but they do not enhance or facilitate proper running form in the same way a curved manual treadmill does. This provides extra benefits to your indoor training.
- There is no motor on the AirRunner since it is a manual tread. The belt moves in conjunction with your foot cadence, so the faster you run, the faster the belt moves. This allows for exceptionally responsive training since you don’t have to wait for the machine to slow down or catch up to you. It also makes it much similar to running outdoors.
- The non-motorized design also means you do not have to place the treadmill by an electrical outlet for power. The AirRunner can be placed anywhere in your home or gym. Since it does not rely on electricity to power, it can be used at any time in any facility. If you have a garage gym, but no extra power source, the AirRunner is a great option.
- There’s no tripping over or moving cords or cables when rolling the AirRunner.
- The console is an LCD screen with control buttons on the right side. It is firmly attached to the horizontal handlebar and runs on four AA batteries.
- For a manual treadmill, this is actually a pretty impressive console. There are numerous programs you can run and the Rest/Work lights are very helpful.
- The console has multiple programs for intervals, target programs, and heart rate programs. There is also a yellow light for rest and green light for work to help you easily know how to pace your intervals.
- The screen is not super large, but the numbers are digital. Time elapsed, calories, distance, speed, watts, pace, and heart rate are all displayed.
- An enter and start/stop buttons sit at the base of the console.
- The AirRunner has a slat belt design, which means it is constructed of individual rubberized slats placed horizontally along the deck. Each slat is a composite material with a textured tread so your foot doesn’t slip while running. The treads are placed close enough together to ensure a constant surface underfoot.
- Slat belts look different than traditional tread belts, which feature a single piece of material that wraps around a tread deck. Since the slat belts are a v-shape design, with the flat edge on top, they are nearly indestructible. The AirRunner belt is advertised to last up to 150,000 miles. A bit of lubricant may be needed from time to time, but the slats will not wear out. This makes these belts much more durable.
- The slats sit on 100 bearings that line the sides of the deck. The belt is also supported by twelve running belt guide pulleys that facilitate smooth motion. The AirRunner does not have a flywheel, so all motion is runner controlled. This does make it slightly more challenging to run on (other manual treads do have a flywheel), but the belt never feels like it is getting ahead of you or pulling you along. On the AirRunner you are in control throughout your routine.
- Slat belts support non-motorized running much better than a traditional sliding belt. The weight of the slats combined with the resistance in the belt makes it more challenging to run on a manual, slat machine which is one of the main reasons runners burn so many more calories with this design. However, the construction of the slats and the method by which they rotate over the deck creates a hearty running surface that is both durable and supportive.
- The console is both Bluetooth and ANT+ enabled, so it will pair with any Bluetooth or Garmin device. This allows runners to store their metrics in their personal app for future reference and comparison
There are several benefits to running on a curved treadmill:
- The curved design supports proper foot strike. The best foot strike pattern is a midfoot strike with a roll through the ball of the foot and a strong toe-off. Many runners develop a heel strike pattern that can cause hip and knee pain with prolonged running. Due to its curved design, the AirRunner naturally pushes runners away from the front of the machine and towards the middle. At this angle, it is more intuitive to run with a midfoot strike as your front foot reaches footward, connects midfoot with the curved belt and pushes it back, releasing contact at the point the backend starts to curve up. This is one of the main reasons why conditioned athletes and seasoned runners used curved treadmills.
- A curved treadmill burns calories faster. Running on a curved, manual treadmill burns 30% more calories than running the same speed on a flat treadmill. This is in large part because it is more difficult. Rather than a tread belt that moves automatically underneath you, a curved slat belt treadmill is only powered by your cadence. This requires much more work by the runner to move the belt.
- Curved treadmills are perfect for High-Intensity Interval Training (HIIT). You’ll increase your heart rate faster and keep it up, increasing your need for oxygen and helping torch more calories than regular aerobic exercise.
- A curved treadmill engages more muscle groups.Curved treadmills force your legs to provide all the motor power, which engages everything from your glutes to your hamstrings.
- A curved treadmill is less harmful on joints. The rubber surface of the AirRunner helps absorb the impact on your joints and connective tissue as you run. This helps prevent overuse injuries. While the cushioning on the AirRunner is not as soft as on the NordicTrack incline trainers or Woodway Curved Tread, it is certainly better than training outdoors on asphalt or concrete.
Incline / Decline range
- There is no incline or decline on the AirRunner. It has a fixed, curved frame.
- Noise level on the AirRunner is commensurate with running on other slat belt treads. There is a bit of impact noise as your foot hits the tread, but there is no motor, so you don’t have background motor noise while running.
Storage / Folding
The AirRunner does not fold, but it has wheels and a lift bar so you can tilt and roll it when necessary.
Assault Fitness claims the AirRunner tread belt will last up to 150,000 miles. Most users report favorable experiences with the AirRunner. There are a few reports of the belt wearing out or getting noisy before the 150,000 mile mark, but Assault Fitness offers a 5-year frame, 2-year parts, and 1-year labor warranty. It is also significantly less expensive than comparable manual curved treads by nearly half, so we find the AirRunner to be a good value.