The PWC-170 Cycle Test

What 's The Point?

Measuring power output (watts) is an accepted way of measuring a cyclists training development. If their power output at a given heart rate (measured as bpm) increases over time, then their training program is effective.

What Do You Need?

• A cycle ergometer
   
• A heart rate monitor
   
• A stopwatch
   
• An assistant

How Do You Do The Test?

After a thorough warm up, the athlete performs two consecutive six minute bicycle ergometer rides in the first one the workload is selected to produce a heart rate between 120 and 140 bpm, on the second one the workload is selected to produce a heart rate of between 150 and 170 bpm.

For each session, the average Heart Rate (bpm) and Power Output (watts) are recorded.

What Results Will I See

By performing the test regularly you will be able to track the progress of the athletes power output. The calculation of this is performed as follows:

Calculations

• Use a graph to plot the two points: X axis = Power (Watts) and Y axis = Heat Rate (bpm).
• Draw a straight line through the two points so that it is extended to 170 bpm.
• Draw a perpendicular line from the point plotted at a heart rate of 170 bpm to the X axis.
• Read off the projected power output at this point.

Example: An athlete produces the following test results:

Session 1 - average heart rate of 130 bpm at 100 watts (600 kg/minute)

Session 2 - average heart rate of 153 bpm at 150 watts (900 kg/minute)

Power output = (((P1 HR2) - (P2 HR1)) (HR2 - HR1)) + (170 ((P1 - P2) (HR1 - HR2)))

Where:

P1 = Power (watts) for session 1
P2 = Power (watts) for session 2
HR1 = Heart rate for session 1
HR2 = Heart rate for session 2

Power output = (((100 153) - (150 130)) (153-130)) + (170 ((100-150) (130-153))
Power output = ((15300 - 19500) 23) + (170 (-50 -23))
Power output = -182.61 + 369.57
Power at 170bpm = 186.96 watts

What's Being Measured Again?

This test measures a cyclists power output at a pre-determined heart rate.