3 Ultra-Effective Exercise Machines You’re Not Using, But Should Be

It’s easy to get into a gym routine and just bust in, do your thing, and leave. We all do it. (Especially in this nasty cold weather: have you SEEN the 10 stages of running when it’s freezing outside? Yeah.) But in case you haven’t noticed, the gym is filllled with cool machines—and chances are, you haven’t tried all of them out yet. Translation? One of them could be your new gym BFF and you simply haven’t given it to the time of day it deserves. So we asked Greg Justice, an exercise physiologist at AYC Health & Fitness in Kansas City, for the top three machines he notices that people don’t use enough—but really, really should. Try at least one of them next time you go!

The Stair Climber

Yeah, yeah, it may or may not elicit Jane Fonda flashbacks. But even though you practically never see anyone on the thing, it’s a winner and it deserves to make a comeback. You burn more calories using the stair climber than walking on the treadmill at the same pace, explains Justice, because you’re involving more muscles, like your hamstrings and your glutes.

The Rowing Machine

Like the stair climber, this machine tends to just sit in most fitness centers, gathering dust—but it’s another overlooked gym gem! That’s because it works so many muscles groups at one time—your quads, hamstrings, glutes, back, shoulders, and core—which is really unusual for most cardio equipment. To maximize your calorie torch, check out these tips for how to burn more calories while rowing.

Suspension Trainers, like the TRX

Those are those things that look like belts that hang down from a pole and you swing in them…you follow? Justice says that they’re underused, probably because they look so innocent—people think, “It’s just a belt; how much can it really help?” A lot. The cool thing about them is that you control the resistance just by adjusting your body position. And also, they enable you to get a fast, effective, total-body workout in a short amount of time. Win! Check out this intense TRX Total Body Workout to get an idea for how to use them.

One caveat, of course: Be careful not to go trying every machine at the gym, though—some really do do more harm than good, like these 10 exercise machines to avoid.

This article was written by Annie Daly and originally appeared on Time.com.