Bruce protocol: A standardized multistage treadmill test for assessing cardiovascular health, The test was developed and described in 1963 by the American cardiologist Robert A. Bruce (1916-2004).
According to the original Bruce protocol, the patient walks on an uphill treadmill in a graded exercise test with electrodes on the chest to monitor the EKG. Every 3 minutes, the speed and incline of the treadmill are increased. There are 7 such stages and only very fit athletes can complete all 7 stages.
The modified Bruce protocol is an alteration in the protocol so that the treadmill is initially horizontal rather than uphill, with the first few intervals increasing the treadmill slope only.