The Standard Bruce exercise test protocol requires a change in speed and grade every 3 minutes. The incremental increases of work are 2-3 Metabolic Workloads (METs) greater for each stage.
The test begins with a 10% incline/grade and 1.7mph pace.
After 3 minutes, the grade increases to 12% and the speed to 2.5mph. The workloads increase every 3 minutes unless arrhythmias or symptoms preclude continuance or until one reaches a predetermined endpoint such as Target Heart Rate or Stage Goal.
Stage 1
1.7mph
10%grade
Stage 2
2.5mph
12%grade
Stage 3
3.4mph
14%grade
Stage 4
4.2mph
16%grade
Stage 5
5.0mph
18%grade
Stage 6
5.5mph
20%grade
Stage 7
6.0mph
22%grade
The Modified Bruce protocol starts at a lower workload than the Standard Bruce, and is typically used for patients who are deconditioned and/or post MI, whose history suggests symptoms at a low workload, and for elderly or sedentary patients who may not be able to keep pace with the faster Standard Bruce protocol.
Stages 1 and 2 of the Modified Bruce are performed at 2.9 and 3.7 METS and the third Stage corresponds to the first Stage of the Bruce protocol. Thus, the person who does 9 minutes in the Modified protocol does the same workload as 3 minutes on the Bruce; 12 minutes on the Modified is the same as 6 minutes on the Standard Bruce.
If you are conditioning for the FAA’s stress test
see: tmst.htm
