His doctoral thesis concerned the measurement of anaerobic threshold in the sport of running.

Although exercising at lower intensities will improve aerobic conditioning, the most rapid gains are made when exercising close to an individual's anaerobic threshold.

This in turn can help a person to maintain an appropriate level of consumption and utilization by studying a graphical representation of the anaerobic threshold.

This tends to be at a heart rate of approximately 20-40 bpm less than the anaerobic threshold and correlates with about 65% of the maximum heart rate.