Alternatives to treadmills for exercise testing

Our vascular lab recently lost access to our treadmill for exercise testing for arterial dopplers. As a result, we have not been offering this test. I am wondering if anyone has heard of an alternative manner of excercising the patient which would take up less room than a treadmill, but still be consistent.

Any help would be appreciated

John Doe
Vascular Surgeon
Dallas, TX
+1 214-214-2142