The plethora of machines at the gym do different things, sure — but you can’t go wrong when you choose one. Whether you walk, jog, or pedal, you’re bound to get your heart pumping for a healthy dose of exercise. But if you have specific fitness goals in mind, that’s when the differences between treadmills and bikes start to matter.
“Both bikes and treadmills are great for training cardiovascular endurance,” David Robertson, an instructor at CycleBar, tells Bustle. “Both can also help you build strength in your legs, particularly by increasing resistance on a bike and increasing incline on a treadmill.”
The two machines diverge when it comes to their effects on your joints, the muscle groups they work, and the specific kinds of workouts you can do on each. And each has its advantages. Here, fitness trainers compare working out on a treadmill vs. a bike so you can pick the right one for your exercise needs.
Exercise Bike Benefits
Pedaling on a stationary bike will strengthen your quads, glutes, and hamstrings, and you work different parts of your lower body depending on your pedaling motion. “The quad muscles work to extend the knee, so every time the legs push down on the pedals it works those muscles,” TJ Mentus, an ACE certified personal trainer, tells Bustle. “If you use a spin bike and spin shoes that clip into the pedals, you’ll work the hamstrings as you pull the pedals up.” Exercise bikes also target your core muscles, Robertson adds, “which should be engaged throughout your ride.”
Again, there’s lots of cardio to be had, especially if you pedal hard and increase resistance, a feature many stationary bikes offer to simulate cycling uphill. “The immediate benefit is improved cardiorespiratory performance,” Mentus says. “Working out on the bike will increase your heart rate as well as breathing, thus working the heart and lungs and improving fitness.”
Keep in mind: There are quite a few different styles of stationary bikes, including upright, recumbent, and even fan bikes (also known as assault bikes). You power fan bikes manually by pedaling and sometimes pulling on moving handlebars, which helps to strengthen the arms and back. Upright bikes, the kind typically found in spin classes, hit the quads, calves, glutes, and core. Recumbent bikes, where you kick back in a seat and pedal, zero in on those quads.
Bikes also have less impact on your joints than many other exercise machines. “I would recommend riding a bike to someone who wants a low-impact workout — perhaps if you’re recovering from an injury or are [...] looking for something that won’t create a lot of wear and tear on your joints,” Robertson says.
Stationary Bike Features
On a bike, you’ll be able to set it up so that you’re in a proper position for your workout. “Most stationary bikes have controls to adjust your seat height, seat distance from the handlebars, handlebar height, and handlebar distance from the seat,” Robertson says.
The main variable you get to work with on an exercise bike? Resistance, which will make it harder or easier to pedal. Depending on the model, the bike might even show how far you’ve biked, how fast, and for how long. “Some may have heart rate trackers in the handles as well,” Mentus says. “With both a spin and a stationary bike you can manually adjust the resistance. With a spin bike you are completely in charge whereas stationary bikes might have preset programs that will adjust the resistance at certain intervals.”
Workouts You Can Do On A Stationary Bike
Hopping on a bike and pedaling for 10, 15, or 30 minutes totally counts as a workout. But if you want something a little more robust, consider interval training. “An interval involves dialing up the intensity to push your body and increase your heart rate,” Robertson says. And there are three ways to do so: increase your speed, increase the resistance, or increase both.
“An interval can last anywhere from 15 seconds to a minute and should feel uncomfortable,” Robertson adds. “An example of interval training would be to push your speed (RPMs) to a challenging pace for 30 seconds and then rest at a comfortable pace for 30 seconds, repeating that sequence for however long you want.” You’ll be dripping in sweat by the end.
Treadmill Workout Benefits
While you can always exercise on a bike and a treadmill, there are plenty of reasons to hop on a tread. “Whether you walk, jog or run, working out on a treadmill is great for improving your cardiovascular health as well as strengthening your muscles and joints,” Steve Stonehouse, a certified run coach and director of education at running studio STRIDE, tells Bustle.
Exercising on this machine will strengthen the glutes, quads, hip flexors, and calves — and you’ll get an added burn in those lower body muscles if you bump up the incline so that it feels like you’re walking or running uphill. It’ll also work your core, especially if you have to lean forward. “These are the [muscles] you use naturally when you run or walk,” says Sarah Pelc Graca, a NASM-certified personal trainer and founder of Strong With Sarah.
In terms of the strain on your joints — like your knees — a treadmill brings more than a bike but less than running outside. “Treadmills offer a softer running surface than concrete outside, so you save your joints from some of the impact of logging miles outdoors,” Stonehouse says.
Treadmills will typically allow you to change the speed and the incline. “They also tell you the speed the belt is running at, the time elapsed, your mile pace, and sometimes your heart rate through the handles.” Many treadmills include preset programs that change speed and/or incline or simulate competing in a 5K.
Workouts You Can Do On A Treadmill
A treadmill workout doesn’t have to be fancy to be beneficial. “When you just want to increase your fitness level, [you can build] your stamina and endurance by going at a slow and steady pace,” Graca says. But if you want to branch out, try HIIT-style interval training.
“Intervals on a treadmill involve increasing your speed or incline for a period of time,” Stonehouse says. “For existing runners, doing interval work improves their running efficiency. For folks who don’t consider themselves ‘runners,’ interval workouts are a great way to introduce some mileage in small chunks, which lets your body adapt and can help prevent injury.”
Treadmill Vs. Bike
The overall consensus? An exercise bike is ideal if you’re looking for a more low-impact workout or are dealing with an injury, while a treadmill is your best bet if you’re in the mood to run or are training for something specific. “If someone wanted to run a marathon or similar style race, obviously the treadmill would be a great choice,” says Graca. “The same goes with biking. If you are training for a specific biking event, you can go with the stationary bike route.”
In terms of the machines themselves, bikes are a bit safer. Since you’re the one powering the machine, it’s much easier to slow down and stop, “which is less dangerous than a treadmill that has a continuous belt moving,” says Mentus.
If you’re just looking for a machine that’ll provide some cardio in your fitness routine, you can’t go wrong with either.
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Sarah Pelc Graca, NASM-certified personal trainer
TJ Mentus, ACE-certified personal trainer
Steve Stonehouse, USATF certified run coach