10 Best Curved Treadmills 2025 in the United States

The Sunny Health & Fitness Smart Ultra Manual Treadmill (SF-X7110) is a curved, non-motorized treadmill designed primarily for high-intensity workouts with magnetic resistance. Its spacious running surface (59 x 17.7 inches) offers plenty of room for walking, jogging, or sprinting while encouraging natural running form thanks to its curved deck. The treadmill supports users up to 330 lbs, which suits a wide range of adults. One notable feature is the adjustable magnetic resistance with eight levels, allowing you to control workout intensity without needing electricity. This makes it a good choice if you want a durable, low-maintenance treadmill that offers a smooth, quiet exercise experience.

The build quality looks solid, with an alloy steel frame and premium belt components for stability and shock absorption, easing joint impact during workouts. Portability is decent for its heavy-duty build; it weighs 157 pounds but includes transport wheels and handlebars to move it around more easily. The device also connects via Bluetooth to the SunnyFit app, giving access to many guided workouts and tracking tools, which can make exercising more engaging. Since the treadmill is manual and does not have a motorized speed function, your speed depends entirely on your effort; the product lists a maximum speed of 1 mph which might refer to a baseline or default setting rather than a top speed, as users can sprint freely.

Assembly is required, and while the treadmill offers good stability features, it may not suit those wanting quick setup or motor-driven convenience. This treadmill is well-suited to fitness enthusiasts who want a sturdy, joint-friendly manual treadmill for varied resistance workouts and prefer a tech-connected experience without a motor. It may be less ideal if you prefer automated speed controls or a lighter, more portable machine.

The Assault Fitness Runner Pro is a unique curved treadmill designed for those who want a challenging workout without the need for electricity. Its motorless design means that users power the treadmill themselves, which can lead to a more intense cardio session, making it ideal for HIIT (High-Intensity Interval Training) and endurance workouts. The fact that it requires no plug-in makes it versatile for both indoor and outdoor use, and it's easy to transport thanks to built-in wheels. Plus, it comes with Bluetooth and ANT+ connectivity, allowing you to track your progress using various fitness apps, which is a great feature for tech-savvy users looking to integrate their workouts with other tools.

On the flip side, the AssaultRunner Pro is quite heavy at 280 pounds, which could be a concern for those who might struggle with moving it around or have limited space. While it claims to be portable, its size (70 inches in length) may not fit into smaller workout areas easily. Additionally, assembly is required, which might not appeal to everyone. Although the treadmill is designed for intense workouts, users who prefer a more traditional treadmill experience may find it challenging, especially if they aren't used to the self-propelling nature of curved treadmills.

The weight capacity is impressive at 350 pounds, making it suitable for a larger range of users. The build quality, made from alloy steel, appears solid and durable, ensuring it can withstand tough workouts. The 5-year frame warranty and a 3-year warranty on moving parts indicate a good level of confidence in its durability.

The AssaultRunner Pro is best suited for fitness enthusiasts who are keen on high-intensity workouts and appreciate the flexibility of a self-powered treadmill. However, those looking for a compact, user-friendly option or who prioritize a traditional treadmill experience may want to explore other alternatives.

The RUNOW Curved Treadmill is a non-electric, motorized treadmill that caters to a wide variety of users, from athletes to office workers, thanks to its versatile and user-friendly design. A major highlight is its ability to burn 30% more calories compared to traditional treadmills, making it a great choice for those looking to maximize their workout efficiency. The running surface is ample at 48 inches long, which should accommodate most users comfortably. It supports a substantial weight capacity of up to 400 pounds, making it accessible to a broad range of body types.

Its weight at 287 pounds may pose a challenge for those needing to move it frequently, despite the two transport wheels included for this purpose. The treadmill features a manual resistance adjustment with four levels, which can be beneficial for customizing workouts. The build quality is robust, with alloy steel construction and a rubber tread for good shock absorption, contributing to its durability and low maintenance needs. The 5-inch LCD screen provides essential workout metrics, although it may be considered small by some users.

Additionally, the treadmill does not have an electric incline adjustment, which might be a drawback for users looking for more advanced incline options. With a warranty of up to 5 years on the frame, the RUNOW Curved Treadmill offers good value and service. This product is ideal for those seeking a solid, manual treadmill for high-intensity interval training (HIIT), running, or walking without the need for electricity but may be less suitable for users who prioritize portability or advanced electronic features.