Before revision: Level 1 - 10%DIF < incline at 2.7 km/h Level 2 - 12%DIF < incline at 4.02 km/h Level 3 - 14%DIF < incline at 5.47 km/h Level 4 - 16%DIF < incline at 6.76 km/h Level 5 - 18%DIF < incline at 8.05 km/h Level 6 - 20%DIF < incline at 8.85 km/h Level 7 - 22%DIF < incline at 9.65 km/h Level 8 - 24%DIF < incline at 10.46 km/h Level 9 - 26%DIF < incline at 11.26 km/h Level 10 - 28%DIF < incline at 12.07 km/h History Before the development of the Bruce protocol there was no safe, standardized protocol that could be used to monitor cardiac function in exercising patients.
After revision: Stage Minutes %DIF > grade MPHmin/mile km/hmin/km METSm/s 1 3 10 1.7 35:18 2.7 22:13 30.75 2 3 12 2.524:00 4.0 15:00 4-51.11 3 3 14 3.417:39 5.5 10:55 71.52 4 3 16 4.214:17 6.8 8:49 101.89 5 3 18 5.012:00 8.0 7:30 142.22 6 3 20 5.510:55 8.9 6:44 172.47 7 3 22 6.010:00 9.7 6:11212.69Total Duration = 21 minutes History Before the development of the Bruce protocol there was no safe, standardized protocol that could be used to monitor cardiac function in exercising patients.