I was first introduced to curved nonmotorized treadmills (CNMTs) in early 2017 while in New York City on an unrelated project. A TrueForm Runner treadmill had been used for many years at Drive 495 on Broadway in SoHo, and I was asked to give my opinion. My immediate impression was that this type of treadmill required quite a bit more coordination and proprioception than the conventional motorized treadmills. It felt awkward and unsettling initially and could easily be passed off as gimmicky at first glance. And to be quite honest, I’ve never been a motorized treadmill fan at all. As such, the thought of running on any treadmill—compared to overground running and sprinting—was not an attractive option for me. But by the second session of running on the TrueForm the very next day, I started to see the benefits and potential of this device and was motivated to try other brands and see if all CNMTs are created equal. In this article, we will discuss the reasons why they may not be.

The challenges presented by the recent global pandemic and the associated stay-at-home orders around the world made training for performance or fitness a major headache over the last few months. I had many clients—both teams and individuals—wondering how to stay in shape at a time when gyms, tracks, and playing courts and fields were closed to everyone. And even though some restrictions are now lifting, the demand remains for equipment that allows individuals to stay home, distanced from groups of people who could transmit the virus. Regardless of the throngs of manic people rushing back to beach parties and barbecues, there is still the silent majority who don’t want to gather socially.
In the case of running and sprinting activities, we’ve experienced some unique challenges during the lockdown’s peak. While it was understandable that many people didn’t have access to a full complement of weights, it didn’t help that some were afraid to go outside to run, sprint, or jump around. In some cases, inclement weather added to the reasons to avoid going outdoors, making many athletes feel literally trapped in their homes.
All of these constraints made me reconsider the use of CNMTs as a primary training stimulus for all sports. Performing running drills on the spot, tethered by a resistance band to a doorknob or bedpost, can only take you so far. With the help of TrueForm, I was able to connect athletes and teams with a training modality that served many purposes, with sprinting as the foundational activity to prepare for the return to sport. This included athletes playing professional basketball, baseball, football, and ice hockey.
Curved nonmotorized treadmills are now one of my primary equipment recommendations in my consulting and course offerings, says @DerekMHansen. Share on XThe ability to engage in locomotion at maximal velocity with the TrueForm treadmill has certainly been a game-changer during this time. Listed below are a few of the key reasons why people have gravitated toward the TrueForm and similar products lately, and why it’s been one of my primary equipment recommendations in my consulting and course offerings.
General Benefits of the Curved Nonmotorized Treadmill
There are many benefits to using a CNMT, whether you’re a serious runner, competitive athlete, or simply a fitness participant. Being able to step on a treadmill and begin running without having to figure out your desired speed or fear of being swept off the deck by a malfunctioning motor provides great convenience and comfort. For first-timers, stepping on a CNMT deck can be a little bit of a balancing act, but the brain and body adapt quickly. This feature also makes it very easy to use with rehabilitation patients beginning to walk or jog on a treadmill. They can set their speed based on self-assessed ability and confidence, as opposed to needing a practitioner to designate a speed for them. The benefits greatly outweigh the challenges with this technology, and users will quickly gravitate toward the device’s more natural feel. Collectively, the benefits listed below provide great incentive to investigate the value of CNMTs for all types of running-related work for athletes, fitness participants, and rehabilitation patients.
1. Accommodation of Step-to-Step Variability
I’ve always felt awkward running—or even walking—on a conventional treadmill. I’ve never found the correct speed for walking, running, or sprinting on a motorized treadmill, which always involved tinkering with the speed buttons to find some semblance of a sweet-spot for my particular gait. Science and research have shown that everyone experiences some degree of step-to-step variability when it comes to movement velocity and ground contact time. Some steps provide more propulsion, while others lead to more braking forces. There tends to be higher variability at slower speeds because the skeleton, joints, and muscles engage in a type of negotiation with the ground from step to step.3 Gait symmetry is more attainable at higher speeds due to the short ground contact and support periods as well as elastic responses, providing even more support for a sprint-based approach to improve running form and overall symmetry.
When running on a motorized treadmill, you have to move at the set speed of the treadmill belt, while a CNMT accommodates your unique step-to-step differences more readily. Experienced runners will notice an immediate difference while novices will quickly acclimate and find comfort in the treadmill’s adaptation to their rhythm and pace, rather than the other way around. A rehabilitation patient will benefit from the variability permitted by the CNMT during the early stages of treatment and won’t feel nervous about searching for an appropriate pace to fit their particular circumstances. The difference in feel is analogous to listening to the variable rhythm of a drummer in a band versus a repetitive drum machine. The human drummer is much more enjoyable to the human ear and brain, just like running on a manual treadmill.
2. Overload Abilities
CNMTs generally provide a relatively significant increase in the physiological cost of running when compared to overground running and motorized treadmills. Several studies have demonstrated differences between these modes of running, finding that CNMTs require approximately 20% more effort—determined by assessing VO2 and heart rate—than overground running.1, 5 Researchers attributed the additional effort to having to run on an inclined deck—essentially uphill—on the upward curved portion of the CNMT deck and having to move a heavy treadmill belt manually.
Curved nonmotorized treadmills significantly increase the physiological cost of running compared to overground running and motorized treadmills. Share on XThey also found that heavier athletes required less effort to run on the CNMT because their weight helped propel the treadmill belt down the curve and back with greater ease; running over regular ground favors lighter athletes. One thing you’ll notice immediately is how much you sweat when running on a CNMT. If you factor in the additional 20% effort required to run plus the lack of air cooling when running through the atmosphere, this makes perfect sense.
The weight of the treadmill belt can vary from brand to brand and even from model to model within brands. The belt’s weight and the impact on your muscles are certainly noticeable when you run on a CNMT for a given time and then step onto solid ground to perform a short run. It’s as though the posterior chain muscles are hyper-activated by the CNMT, and hip extension is noticeably easier on regular ground. I’ve used this contrast approach in many of my courses where we have a participant sprint maximally for six seconds on the CNMT and then immediately step off the treadmill and perform a ground-based sprint of 20-40 meters. When I ask how the ground-based sprint felt, everyone would reply with either, “It felt like someone was pushing me forward,” or “My knees just came up automatically!” The responses made me think more about the supplemental use of CNMTs for posterior chain development in appropriate doses. It essentially qualifies as a safer form of horizontal loading in the upright sprint position (as opposed to dragging sleds 50-60 meters), and I’ve used it effectively in contrast sessions, mixing it with overground flying start work.
3. Sprint Training Alternative
The COVID-19 pandemic has certainly made it a challenge for people to sprint both indoors and outdoors. Closures of gyms, track, and outdoor fields have made it virtually impossible to do a good sprint workout. Sprinting on asphalt or concrete is a reasonable way to get high-speed work accomplished. Still, the impact on the feet, ankles, shins, knees, and back becomes apparent after only a few workouts and the constant repetition of decelerations required over time.
As we're moving back to outdoor activities, we've seen technical improvements & physiological abilities transfer from curved nonmotorized treadmills. Share on XMany of my clients have access to CNMTs in their homes or their private gyms, and we’ve had to modify their training plans to integrate upright maximal sprinting on these treadmills to make up for the loss in volume via conventional track or field work. Over time, I’ve become comfortable with providing equivalent speed workouts on the CNMT. And, and as we’re making our way back to outdoor activities, we’ve seen some positive outcomes with a transference of technical improvements and physiological abilities.

One of the major adjustments we’ve made when prescribing work on the CNMT is to use time or the total number of steps per repetition as our work indicator, as opposed to distance traveled. Time works well if there’s another person on hand to cue a five- to six-second effort verbally, but having an athlete time their maximal effort can have unwanted side effects. At maximum velocity, the slightest movement of the head down to see the elapsed time on the digital display can throw off posture and technique, resulting in a drop in hip height and poor foot placement. Thus, we’ve adapted some workouts to only rely on the total number of maximal strides for each repetition. If we know an athlete is capable of running 4.5 steps per second at maximum velocity, we will calculate a total of 18 strides for a four-second effort. Typically, I’m replacing a 30-meter sprint with about a five-second effort on the CNMT, as it takes more effort to accelerate overground than it does to start sprinting maximally on the treadmill. To compensate for the lack of access to acceleration work, I also prescribe jumps and plyometrics over short distances to target specific muscle groups and ground contact times associated with starts and short accelerations.
Upright max sprints on curved nonmotorized treadmills had significant effects on output capabilities, general fitness, stress tolerance, & psychology. Share on XI found that using upright maximal sprints on the CNMT for the two months of primary stay-at-home measures during the current pandemic worked quite well for my clients and family. You never want to get too far away from the specifics of sprinting overground, but the intensity of the runs on the CNMT also had some significant systemic effects on individuals in terms of output capabilities, general fitness, and stress tolerance. Also, the ability to sprint maximally when outdoor options were not available provided significant psychological benefits to these athletes, knowing they were accumulating beneficial training at very high intensities when their competition may not have similar opportunities.
4. Video Analysis Abilities
Treadmills have always offered an easy means to video record an effort and analyze it through various apps and biomechanical software programs. The placement of a tripod for a video camera or smartphone allows for a simple and economical way to standardize video analysis. Conversely, filming outdoors is always a challenge when trying to pick a consistent vantage point to compare from repetition to repetition. The perspective outdoors changes constantly, and you may only be able to strictly analyze two or three strides if you wish to measure angles and ranges-of-motion.
Curved nonmotorized treadmills proved a realistic, pragmatic way to analyze upright sprint mechanics consistently over 20 to 25 strides. Share on XThe CNMT experience, however, provides a very realistic and pragmatic means of analyzing upright sprint mechanics consistently over as many as 20 to 25 strides. Factor in CNMT’s natural step-to-step variability benefits, and you also can analyze an athlete’s true output abilities. In contrast, the motorized treadmill scenario could be biased by the output of the treadmill itself.


I’ve often used multi-camera setups for my sprint work with athletes on the TrueForm Runner and Trainer models. Capturing sprint repetitions from the side, front, and rear views is very effective for collecting valuable data in a short amount of time. I’ve even situated cameras for slow-motion close-ups of an athlete’s feet contacting the belt to analyze ground dynamics, ultimately giving the athlete different cues or involving a physical therapist to address any specific concerns.
5. Performance Training At Home
Training at home has never been an exciting prospect regardless of whether you’re lifting weights, doing body-weight circuits, or performing drills in a corridor or across the dining room. Having a CNMT at home during the global pandemic has been a game-changer for my family and me. I have three kids at home who did not get to participate in the spring track season, which would have included numerous training sessions and valuable competitions over 100-, 200-, and 400-meter distances. Hence, the canceled track season left us with an enormous hole in their training and performance preparation.
Being the overzealous sport parent that I am, I quickly jumped on the CNMT bandwagon and ordered a TrueForm Trainer right away. As soon as it arrived, I quickly assembled it and had my kids taking turns to get accustomed to the dynamics of the curved deck and weighted belt. Before you know it, we had a whole series of workouts and competitions taking place in my basement with no complaints from the kids. It’s been a pretty amazing experience, all helped by the fact that the CNMT offered both a degree of novelty and reality. All of the kids were able to deliver maximal efforts on the CNMT and process technical instruction quite easily. Because we could record their repetitions with our smartphones, we could show how they should approach the next repetition. More recently, we were able to go to a nearby park and perform some sprints over various distances, and my wife was surprised at how good each of them looked. The home-based performance experiment was complete, and the investment paid off. Now we have the treadmill available for training during inclement weather, particularly during the winter months, when it’s virtually impossible to run fast outdoors.
6. Social Media and Virtual Training Opportunities
Because of all of the facts identified above, the CNMT now presents an interesting opportunity to share performance, training sessions, and running mechanics easily on social media. Yoga, dance, and weightlifting have been easy to share over social media because of their stationary qualities and ease of video recording. Running hasn’t been so easy to capture and convey on Instagram and TikTok. However, the use of CNMTs offers a new way to capture running technique and the quality of movement displayed by athletes. While some videos have focused on speeds attained on CNMTs, I believe there is a greater benefit from demonstrating good technique for everything from sprinting to interval training to longer-distance efforts.

I’ve been using Zoom and Facetime to guide coaches, physical therapists, and athletes on how to carry out workouts effectively while also giving useful tips on running technique. I record these sessions and pass them on to the clients to review before our next training session, giving them some homework upon which to develop their technique further. Some clients have set up heads-up displays that are cast onto HDTVs or projected onto walls to ensure they can maintain posture during our sessions. You can stream video using a GoPro or similar technology to provide high definition views of every repetition.

Ideally, all athletes would have access to a CNMT to allow for opportunities to receive remote coaching from experts. While we would like to think that good coaches exist in every corner of the world, the reality is that people must search for the best possible options to ensure they’re getting experienced and capable eyes watching them move. The CNMT gives us a chance to provide a realistic training experience that can be adjusted and optimized in real-time regardless of geographical distance. Further advances in heads-up display glasses with video feeds and running metrics streamed from other wearables and in-shoe technology will only make this experience more viable and valuable. The possibilities are endless.
Why TrueForm Treadmills?
Circling back to my introduction to CNMT technology in 2017, some of the reasons I keep coming back to the TrueForm brand are based on confidence, trust, communication, and familiarity. After those initial experiences running on the TrueForm, I made an effort to try other brands to see where the true differences lay. Because I was in New York City, finding other brands was very easy and conveniently only a few blocks away from Drive 495 on Broadway. I was able to try a Woodway Curve, a Technogym SKILLMILL, and an Assault AirRunner, all within a few days of my first workouts on the TrueForm Runner.
At first, I didn’t notice any significant differences from treadmill to treadmill. They all had curved decks and slatted belts. The handrail configuration differed slightly, I could detect subtle differences in the steepness of the curves, and the weight of the belts varied. Some were noisier than others. And the prices varied significantly. So which treadmill was the best fit and value for what I was trying to do, and would I feel comfortable recommending a particular brand to friends and clients?
TrueForm was the winner for a variety of reasons. Value is one of the biggest factors in picking any product. Sure, I’d love to have deep pockets and choose the most expensive equipment to outfit a facility or train my clients. However, we must set limits and include other considerations before pulling the trigger. Below are my reasons for going with the TrueForm products for my training, my courses, and recommendations for individual and team clients.
1. Versatility
One of the first places I had a TrueForm Runner installed was a physical therapy clinic where I offer my services. The flatter curve of the TrueForm allows me to transition patients from slow walking to fast walking easily and then jogging and faster running throughout their locomotion rehabilitation. I use it with patients recovering from knee replacements, ACL reconstructions, hip replacements, sprained ankles, Achilles ruptures, hamstring strains, and quadriceps tendon avulsions. Patients are surprised at how easy it is to move on the TrueForm and also comment that they could feel it working other muscles up the chain, including back and abdominal muscles. Patients also need very little monitoring for their workouts because they can choose their speed and comfortably complete their session. There’s no fiddling with speed settings or incline adjustments. The TrueForm treadmill offers a combination of simplicity and novelty that everyone enjoys without creating any fear or uncertainty.

On the other end of the spectrum, I use the TrueForm with sprint athletes to work on their top-end speed and associated mechanics. It’s very easy to encourage faster running and efficient mechanics by propping up the front end of the TrueForm with a block of wood or a weight plate. Even an inch of elevation can be a great stimulus for athletes to find their groove for high-speed running. When some people argue that other brands with a steeper curve would be better for high-speed running, I always remind them that the versatility of the flatter curve gives me many more options for working with a wider variety of clients and patients. I can prop up the front end of the TrueForm in less than a minute to fit the needs of my high-performance clients.
2. Durability
One of the biggest draws of the TrueForm line of treadmills is their durability. My good friend and podcast partner, Don Saladino, has had a TrueForm Runner in his Drive 495 facility for over four years. Knowing how much maintenance is required for high-end motorized treadmills, I remember asking him how much maintenance the TrueForm required. I recall him saying, “I don’t think we’ve had to do anything for the TrueForm except wipe it down. It’s bulletproof!” And ever since, I’ve heard the same story from other gym owners and teams who’ve purchased TrueForm products.
Durability is a significant factor for any gym considering a purchase of over $5,000 for a piece of equipment. The less a facility owner has to worry about maintenance and potential breakdowns, the more attractive the investment, particularly if it’s a popular piece of equipment. I’ve seen TrueForm treadmills in Cross-Fit facilities that had to be hosed down at the end of the day from constant intense use by gym members. TrueForm has also held outdoor events and competitions in beach environments where the treadmills get covered in water and sand, with no impact on the performance or longevity of their machines.
For homes or small fitness studios, there is much less wear and tear and overall volume of use. Thus, the choice of the TrueForm Trainer makes a lot of sense for consumers who want the convenience of being able to sprint or run at home. Knowing that TrueForm wanted to create a more affordable option for consumers entering the CNMT market, I was a little apprehensive initially about the “cheaper” overseas-produced model, knowing the solid reputation of the American-built TrueForm Runner product. However, I’ve been pleasantly surprised at both the build quality and performance of the Trainer model, and we’ve been using it almost daily for walks, tempo runs, or sprints. I expect to be using this piece of equipment for well over ten years.
3. Support
When buying any product that is a significant financial investment, you want to make sure you have the best possible customer support moving forward. From the beginning, I’ve been exceptionally impressed at the quality and frequency of communication I’ve had with the TrueForm crew from day one. The company essentially has four employees who run things efficiently and effectively because the circle is tight, and the right hand always knows what the left hand is doing. If I have a question, Jeff or Zack at TrueForm get back to me by text or email within the hour and provide a solution. As a running coach who relies on this equipment for my day-to-day consults and coaching sessions, having the ability to troubleshoot any hardware issues with staff right away is a huge confidence and trust-building factor in my decisions around purchases and recommendations. If I know a product is not only reliable but also well supported, it’s a no brainer decision for me.

TrueForm has also been very receptive to recommendations for updating the treadmills based on my personal experiences. They’ve adjusted the handrails forward to allow for more room and a greater emphasis on front-side mechanics—for both the legs and the arms. If an athlete thinks they might clip the handrail with a hand or a knee during a maximal sprint, they alter their mechanics to the detriment of the session. The adjustments made by TrueForm to accommodate these mechanics have been very helpful with my athletes and clients. We’ve also discussed various options and innovations for heads-up displays that allow athletes to maintain a higher line of sight for monitoring time, speed, heart rate, and pace. The fact that we’re having these conversations and they’re making changes gives me great confidence in this company. It also communicates to me that TrueForm behaves like a modern technology company, adapting quickly and responsively to their consumers, rather than forcing people to adapt to apathy and lack of imagination.
4. Community
As part of my Running Mechanics Professional courses that I began offering in 2019, TrueForm expressed an interest in being part of these in-person events, to my surprise. There are many opportunities to demonstrate the value of the CNMT technology, and at first, I only covered the intricacies of these workouts if a hosting facility or organization already had a CNMT on hand. I soon realized that not all CNMTs were created equal, and I got stuck with some lower quality models for my courses; I wasn’t pleased with the outcome of the demonstrations and the user experience for course attendees. When TrueForm heard about this, they committed to providing both TrueForm Runners and Trainers at various courses. We had the TrueForm crew deliver treadmills to New York, Montreal, and Kansas City during the summer of 2019, making all of the events a great success.

More importantly, the trips by TrueForm staff conveyed to me a sense of community and commitment to exposing their product to various markets and professionals by any means necessary. Watching them unload dozens of treadmills from their truck and trailer after a long road trip is inspiring. When we held a running clinic at Drive 495 in SoHo New York in 2018, TrueForm did not hesitate to commit 12 TrueForm Runners to the event to give people a chance to sprint and run on their product. They also provided custom graphics to support both Drive 495 and SprintCoach.com, which made a huge difference to the branding around the event. And I’ve witnessed TrueForm staff hauling their trailer all over the country to attend Triathlon, Cross-Fit, and Spartan Race events wherever they can. They are truly committed to developing a community around their product.
5. Customized Graphics
TrueForm has a fantastic option for customers who want to personalize their treadmill to display their brand. Using a local graphics company, they provide custom decals and wraps for customers that add some flash to the end product. There have been numerous teams, athletes, and celebrities who’ve taken advantage of this feature and have been ecstatic with the results. I recently connected TrueForm to a popular social media influencer who likes to train furiously in his apartment, particularly during the stay-at-home orders. Within a few days, they had a TrueForm Runner delivered and set up in his apartment with full graphics displaying his company and brand. He was elated with the results and was training on the TrueForm the next day, producing captivating content for his followers. While this may seem like a gimmicky feature to the TrueForm full service, you can’t discount the impact of an aesthetic upgrade to enhance the overall customer and user experience. It’s been a game-changer from my personal experience in working with clients.

I joined in on the graphics production for my own TrueForm Trainer. In working with my kids, I wanted to demonstrate the concept of moving to the front of the Trainer when they wanted to run faster. I produced decals with a photo printer for these speed zones (illustrated in Image 10), so it was clear what they had to do to run faster. Of course, as you move forward, you have to put more vertical force into the treadmill belt, but they had no problem executing the technique once they grasped the concept. I now have other clients use the same placement of these decals to make sure they understand where they need to be on the treadmill for their various workout activities.

Concluding Remarks
It’s important to point out that there are many high-quality options for CNMT machines available to both organizations and regular consumers. While most people are very price-conscious when analyzing their choices, you do reach a point where you have to pay a certain price to ensure quality, performance, and safety. As with any good technology or product, knock-offs and copycat products will hit the market before you can hit Enter for a Google search. So, consumers must be smart when evaluating all of the options on the market, particularly when budgets are tight. Consider the fact that a good CNMT product should be with you for well over a decade, and you can spread the cost of that purchase over the life of the treadmill. The benefits accrued over this time, assuming consistent use, are invaluable.
I chose to go with TrueForm based on my experience, history, and rapport with the company and the product itself. I feel very comfortable recommending their products because I’ve spent a good deal of time running and coaching on their treadmills. There are other good products on the market you should consider as well. As an example, I had the pleasure of running and coaching on a Woodway Curve XL at one of my courses in Phoenix, Arizona. I was very pleased with the build quality, performance, and roominess, and everyone who tried a few reps on the treadmill felt very comfortable. The extra space on the belt and deck provided a very secure experience for people who had not run or sprinted on a CNMT machine. The only downside of the XL is that it’s much more expensive than the TrueForm models and takes up a much larger footprint in a gym space. But it may still work for a larger facility with larger athletes who want to create the perception of more space while running on a CNMT, assuming the price is not an obstacle.

In the final analysis, as with barbells or medicine balls, it’s what you do with the equipment that will determine whether you made a successful purchase. I love my TrueForm Trainer treadmill because I know exactly how to get the most out of it with my experience and expertise in working with sprint-based athletes for over 30 years. And with the help of the TrueForm owners and staff, I’ve tweaked the technology to maximize the efficacy of every session. This also gives me the ability to work effectively with others who have access to TrueForm products via video calls and the provision of progressive sprint programs.
Because of the tremendous success I’ve experienced with clients and teams over the last few months, I’m developing a sprint-based digital platform for using treadmills to not only coach athletes but also to educate sport, fitness, and rehabilitation professionals on how to effectively use TrueForm products and other CNMT machines with their athletes, clients, and patients. We will be providing real-time educational experiences that simulate in-person sessions and build on the strength of the CNMT training environment. Pivoting and adapting in times of massive change and challenges and using new technologies is all part of the new normal. Jump on board, and I look forward to interacting with you at “high-speed” in the future.
Since you’re here…
…we have a small favor to ask. More people are reading SimpliFaster than ever, and each week we bring you compelling content from coaches, sport scientists, and physiotherapists who are devoted to building better athletes. Please take a moment to share the articles on social media, engage the authors with questions and comments below, and link to articles when appropriate if you have a blog or participate on forums of related topics. — SF
References
1. Edwards, RB, Tofari, PJ, Cormack, SJ, and DG Whyte. “Nonmotorized Treadmill Running Is Associated with Higher Cardiometabolic Demands Compared with Overground and Motorized Treadmill Running,” Frontiers in Physiology. November 2017: 8, 914.
2. Gonzalez, AM, et al. “Reliability of the Woodway Curve Nonmotorized Treadmill for Assessing Anaerobic Performance,” Journal of Sports Science and Medicine. 2013: 12, 104-108.
3. Hatchett, A, et al. “The Effect of a Curved Nonmotorized Treadmill on Running Gait Length, Imbalance and Stride Angle,” Sports. 2018: 6, 58; doi:10.3390/sports6030058.
4. Mangine, GT, et al. “Speed, Force, and Power Values Produced from Nonmotorized Treadmill Test are Related to Sprinting Performance,” Journal of Strength and Conditioning Research. 2014: 28(7), 1812–1819.
5. Schoenmakers, PJM, Crisell, JJ and KE Reed. “Physiological and Perceptual Demands of Running on a Curved Nonmotorized Treadmill Compared With Running on a Motorized Treadmill Set at Different Grades,” Journal of Strength and Conditioning Research. 2020: 34(5), 1197–1200.
6. Seneli, RM, Ebersole, KT, O’Connor, KM and AC Snyder. “Estimated Vo2max from the Rockport Walk Test on a Nonmotorized Curved Treadmill,” Journal of Strength and Conditioning Research. 2013: 27(12), 3495-3505.
7. Waldman, HS, Heatherly, AJ, Waddell, AF, Krings, BM and EK O’Neal. “Five-Kilometer Time Trial Reliability of A Nonmotorized Treadmill and Comparison of Physiological and Perceptual Responses vs. a Motorized Treadmill,” Journal of Strength and Conditioning Research. 2018: 32(5), 1455-1461.