Final answer:
The Bruce protocol is an exercise protocol that can be used to measure the maximum O2, or VO2 max, that can be achieved by a healthy adult male.
Step-by-step explanation:
To measure the maximum O2 that can be achieved by a healthy adult male, the exercise protocol that can be used is the Bruce protocol.
The Bruce protocol is a graded exercise test that involves progressively increasing the speed and grade on a treadmill until the participant reaches their maximum oxygen consumption (VO2 max).
This protocol is commonly used in exercise physiology and sports medicine to assess an individual's cardiovascular fitness and endurance.
The other exercise protocols listed – ramp test using a cycle ergometer, six-minute walk test, and eight minutes of treadmill walking at 2.5 mph, 12% grade – may be useful for other measurements or assessments, but they are not specifically designed to measure maximum oxygen consumption.