For discussion purposes, I take exception to the conclusion. It could be that not enough information was included in your podacast about the study for I to make such an exception.

In today’s power language, peak power normally represents one’s functional threshold power (FTP) level – meaning the average power one can maintain in an all-out effort for one hour. I do not believe a comparison of 80% of one’s heart rate and 80% of one’s FTP is a reasonable comparison. I train with power and performing intervals at 80% of my FTP does not elicit a heart rate close to 80%, rather much lower. In fact, riding at one’s 80% of FTP can be accomplished for quite a long duration with relative ease. 80% FTP is not that challenging. To give a little perspective, most triathletes bike a half-iron distance triathlon in a power range between 85% – 90% FTP. When I do intervals such as those performed in the study, I perform the intervals at 100% of FTP.

You utilize Training Peaks and are likely familiar with the use of Training Stress Score (TSS) which combines duration and intensity into a training load indicator statistic. Intensity has a much greater influence than duration in the calculation of TSS. The greater one’s TSS for a workout, the greater the training load applied to one’s body for adaptation. There is a significant difference in one’s TSS at 80% FTP versus 100% FTP.

I would argue that power training is more beneficial than heart rate training. Heart rate can be viewed as the symptom of work performed. However, heart rate can be affected by a number of variables (heat, dehydration, stress, amount of sleep the night before, etc). These variables can and do skew one’s heart rate, whereas power is power — a watt is a watt. For example, if one is attempting to train at 80% heart rate, but due to the variables discussed their heart rate is influenced to be at a greater rate than normal, then the athlete while adjusting their training intensity to maintain that 80% mark would actually be incurring a lower training load and adaptation than the workout was trying to achieve since in reality they are performing at a heart rate actually lower their real 80% level. Contrast that to power; if workout is to hit a %FTP and that was achieved, then workout achieved desired results without the variables that skew one’s heart rate. The existence of variables skewing one’s heart rate compared to the lack of variables skewing a watt imply that power training is more beneficial than heart rate training, all other factors equal.