The short answer
Elliptical or Stationary bike?
Start on the bike if you have knee arthritis, if you are cleared after a knee operation, or if walking itself hurts. In instrumented knee implants, moderate cycling loaded the knee less than walking, 119% of body weight at 60 W. The elliptical came out lower than jogging but no lower than walking, so it fits knees that walk fine and want something longer. With kneecap pain either can work. Set the bike seat high enough, though, because pressure behind the kneecap tends to rise as the seat drops.
Side by side
| Question | Elliptical | Stationary bike |
|---|---|---|
| What it is | Standing on two footplates that travel in a long oval, with or without moving handles. | Pedalling a fixed bike, upright or recumbent, against a resistance you set. |
| Equipment | An elliptical trainer | An upright or recumbent exercise bike |
| Knee load in implant studies | Lower than jogging, not lower than treadmill walking (3 people) | Lower than walking at every power from 25 to 120 W; 119% of body weight at 60 W (9 people) |
| Your body weight | Standing, carried through the legs, with no landing | Seated, with the saddle taking your weight |
| How far the knee bends | Further than in walking, at both hip and knee | Set by the seat. Too low and the knee folds deeply at the top of each turn |
| Energy cost (2024 Compendium) | 5.0 METs moderate, 9.0 vigorous (codes 02048, 02049) | 6.0 METs at 90 to 100 W, 6.8 general (codes 01220, 01200) |
| 30 minutes at 70 kg (154 lb) | About 184 kcal moderate, 331 vigorous | About 221 kcal at 90 to 100 W, 250 general |
| 30 minutes at 90 kg (198 lb) | About 236 kcal moderate, 425 vigorous | About 284 kcal at 90 to 100 W, 321 general |
| Getting on and balance | Step up and stand, with handles to steady you | A recumbent has a back rest and a low frame to step through |
| What to adjust first | Resistance, then stride length if the machine has it | Seat height, then resistance, then cadence |
Choose the elliptical when
- Walking is comfortable, running is not, and you want something longer and harder than a walk.
- Sitting is the problem: your back or hips stiffen after 20 minutes on a saddle.
- You want the arms working too, on the moving handles.
- You are working back toward running and want a movement close to walking.
Choose the stationary bike when
- Walking itself makes the knee ache.
- You have knee arthritis and want the lower measured knee force of the two.
- You are rebuilding after knee surgery and your surgeon or physio has cleared cycling.
- Balance worries you, and a recumbent bike lets you train seated against a back rest.
- You want exact control, with watts and cadence on the screen.
Using both in one week
Make the bike the base and treat the elliptical as a test. Ride two or three times a week for 20 to 40 minutes. Once the knee has been quiet for two weeks, swap one ride for 15 minutes on the elliptical. No worse that evening or the next morning? Add 5 minutes a week. If it grumbles, go back to the bike for another fortnight. Easy pedalling will not rebuild a weak thigh, though. ACSM's 2026 position stand puts strength gains down to heavier loads, so keep some leg strength work your knee tolerates.
Bike first, then earn the elliptical
- Set the seat so the knee keeps a slight bend, 25 to 30 degrees, with the pedal at the bottom. A rough check: with your heel on the pedal at the bottom, the leg is just straight.
- Ride 10 to 15 minutes at light resistance and a smooth, quick cadence. In the implant study, force rose with power and fell as cadence went from 40 to 60 rpm.
- Add 5 minutes a session up to 30 to 40 minutes, provided the knee feels no worse the morning after.
- Then add resistance, one small step at a time.
- Test the elliptical with 10 to 15 minutes after a short bike warm-up, light resistance, standing tall.
- Grow the elliptical by 5 minutes a week while the knee stays quiet.
The numbers
- Knee force, cycling at 60 W
- 119% of body weightPeak force at 40 rpm in 9 people with instrumented knee replacements, and lower than walking at every power tested (Kutzner 2012).
- Knee force, level walking
- 261% of body weightAverage peak in 5 people with the same lab's instrumented implants (Kutzner 2010).
- Seat height for knees
- 25 to 30 degrees of knee bendAt the bottom of the pedal stroke, the setting a review of 62 references suggested to reduce knee injury risk (Bini 2011).
- Bike, 30 min at 90 to 100 W, 70 kg
- About 221 kcal6.0 METs (code 01220) x 3.5 x 70 / 200 = 7.35 kcal a minute, x 30. A moderate elliptical (5.0 METs) is 184. At 90 kg: 284 and 236.
Mistakes that cost the most
- A bike seat set too low. Each turn folds the knee further at the top, and that tends to raise the pressure behind the kneecap.
- Grinding heavy resistance at a slow cadence. Knee force in cycling rose in step with power.
- Picking the elliptical because it is called low impact when walking already hurts. In implant data it loaded the knee about as much as walking.
- Pulling a recumbent seat so close that the knee comes up toward the chest on every turn.
Questions people ask
Elliptical vs stationary bike for knees: which is easier on them?
The bike, going by direct measurements inside the knee. Instrumented knee implants recorded lower forces in cycling than in walking at every power from 25 to 120 W, while the elliptical came out lower than jogging but not lower than treadmill walking. Both studies were small and used people with knee replacements.
Elliptical or bike for knee pain?
Bike first if walking hurts. If walking is comfortable and only running hurts, the elliptical is a sensible step between the two. With kneecap pain, test the elliptical in short doses, because it bends the knee more than walking and asks more of the thigh at the knee.
Recumbent bike vs elliptical for knees?
A recumbent is a bike with a back rest. The implant studies did not test one, but the pedal motion is the same, and it is the easiest of the three to get on and off. Slide the seat so the knee keeps a slight bend with the pedal at its furthest point. Too close, and every turn crams the knee into a deep fold.
Can I use an exercise bike after knee replacement?
Usually, once your surgeon or physio clears it. The authors of the implant study called moderate cycling suitable after knee replacement. If the knee will not bend enough to take the pedal over the top, raise the seat and rock the pedal back and forth instead of forcing a full turn.
Sources
- 2024 Adult Compendium of Physical Activities: A third update of the energy costs of human activitiesJournal of Sport and Health Science, 2024
- Loading of the knee joint during ergometer cycling: telemetric in vivo dataJournal of Orthopaedic and Sports Physical Therapy, 2012
- Loading of the knee joint during activities of daily living measured in vivo in five subjectsJournal of Biomechanics, 2010
- The Mark Coventry Award: in vivo knee forces during recreation and exercise after knee arthroplastyClinical Orthopaedics and Related Research, 2008
- Joint loading in the lower extremities during elliptical exerciseMedicine and Science in Sports and Exercise, 2007
- Similarity of joint kinematics and muscle demands between elliptical training and walking: implications for practicePhysical Therapy, 2010
- Effects of bicycle saddle height on knee injury risk and cycling performanceSports Medicine, 2011
- Resistance Training Prescription for Muscle Function, Hypertrophy, and Physical Performance in Healthy AdultsMedicine and Science in Sports and Exercise (ACSM position stand), 2026
Figures on this page come from the studies above or from the arithmetic shown. Read how claims are reviewed and updated in How the guides are written.