Reviewers say nearly every aspect of the LifeSpan TR4000i -- from its well-lit, easy-to-use controls to its smooth, efficient ride -- is well thought out. The only exception is its online workout log/USB thumb-drive interface, which could use a little more development.
A solid, gym-quality workout. The LifeSpan TR4000i's 20-by-60-inch running deck and 3.25-continuous-horsepower motor deliver a quiet, solid and smooth experience. "The treadmill has an excellent feel and is very joint-friendly," writes one Amazon.com user who logs 35 to 40 miles each week, adding that it's very quiet. "Very solid and smooth, no bounce," writes another.
Testers with Runner's World magazine agree: "The sturdy deck delivers a steady ride." The TR4000i has 15 levels of incline adjustment and a max speed of 12 mph, although it takes a few seconds to get up to speed.
Easy, intuitive controls. Reviews of the LifeSpan TR4000i's premiere feature -- a USB port that allows you to store your workout metrics on a thumb drive (for upload to a workout website) are mixed. Experts praise the novel idea, but most consumer feedback at Amazon.com suggests it isn't well executed.
The TR4000i's other highlights are better received. Testers with Runner's World say they particularly appreciate how easy it is to hit the large speed and incline buttons while running. Others say both the wireless and handgrip heart rate monitors work well, and the user-defined programs are simple to set up.
High-quality components. In an unusual turn of events, one Amazon.com user found that his treadmill shocked him when he ran on it. LifeSpan customer service inquired about the grounding in his house and sent out a tech to investigate but couldn't figure out a solution. Eventually, the user realized he got shocked only when wearing a particular type of running shoes and on that specific machine.
Aside from that unusual issue, customer reports about the LifeSpan TR4000i's durability have been positive, praising its "gym-like" feel. "The control panel and electronics seem to be solid," writes one runner who, along with others, recommends this machine to those who run anywhere from 30 to 80 miles weekly. One Amazon.com user notes it feels just as solid at maximum incline (15 percent) as flat. The treadmill receives a "very good" rating for its construction from a leading consumer research organization.
You have good odds. The LifeSpan TR4000i is backed by a solid warranty with lifetime coverage on the frame and motor, five years on parts and one year for labor. Although limited, the available user feedback about the company's customer service is promising -- for example, a frequent runner posting to Amazon.com says LifeSpan was very responsive and helpful when he had issues uploading his workout metrics to the workout log website. Another writes that "after about a month the circuit board failed, and I contacted the manufacturer and they shipped a replacement circuit board and had the technician show up and fix it ... all of this was done in one week!"
The LifeSpan TR4000i is one of dozens of treadmills tested in ConsumerReports.org's latest round of treadmill ratings. Each machine is evaluated in several categories, including ease of use and ergonomics, and assigned a comparative ranking. Full details are available to subscribers.
Review: Treadmills, Editors of ConsumerReports.org, As of November 2013
2. Runner's World
Fourteen staffers test nine new treadmills at Runner's World. Each gets a brief paragraph of analysis, but they aren't compared to each other. Testers say they like this treadmill's solid feel and steady ride.
Review: Rise of the Machines, Lisa Jhung and Sean Downey, Jan. 12, 2010
The editors of TreadmillDoctor.com give the LifeSpan TR4000i good scores for walking area, power and warranty, although they recommend purchasing either the next higher- or lower-priced models.
Review: LifeSpan TR4000i Treadmill Review, Editors of TreadmillDoctor.com, As of November 2013
Nearly 20 reviewers weigh in here, giving the LifeSpan TR4000i an average score of 4.4 stars out of 5. Most say it's stable and powerful and that LifeSpan's customer service is responsive.
Review: LifeSpan Fitness TR4000i Folding Treadmill, Contributors to Amazon.com, As of November 2013