ProForm Carbon TLS

Why it's worth it

The ProForm Carbon TLS is a folding treadmill, which makes it the only machine here that lets you actually run rather than glide. It tips up when you're done, so a spare room can go back to being a spare room between sessions.

Nothing on an elliptical teaches your legs to run. If you're training for a 10K, or you just like running and the weather where you live is hostile for four months a year, a treadmill is the tool. You get real gait, real cadence and real hill work when you raise the incline. That's the whole argument for this machine, and it's a good one.

Folding is the feature that decides whether a treadmill survives in your house. A full-size cardio machine is furniture, and furniture in a spare bedroom starts arguments. The Carbon TLS tips up between sessions, so the room stays usable. You give up a little rigidity underfoot compared with a fixed deck, but for walking and easy running you probably won't notice the difference.

From our review of 4 home cardio machines, by Eleanor Vance, Health & Beauty Editor

What we like

• +Nothing on an elliptical teaches your legs to run
• +Folding is the feature that decides whether a treadmill survives in your house
• +It's the least joint-friendly machine we're recommending, and that's not really a knock — it's the point
• +Check the console before you commit

What to know

• –Treadmills are the loudest machines you can put in a home gym
• –A folding deck adds hinges, and hinges develop play over time, so expect it to feel less planted after a few years than a fixed…