To those of you who have a power meter and/or run gps device you may ask yourself from time to time, "What are these things really for?" There are a few reasons these devices can be beneficial. Some of them are obvious and some are not so obvious. The obvious reasons include being able to know how many watts you can produce on the bike or what pace you are maintaining on the run. These factors can be compared to your heart rate and this gives us an idea of how hard you are working. From this you and/or a coach can determine a great deal about where to take your training. However, if you want to take things to the next level you will want to learn and study training stress scores. No longer will you be measuring your long ride or next interval workout by how long you spent in heart rate zone
1-5a. You will be assigning each workout a TSS or Training Stress Score based on duration and measured intensity. This TSS score can be produced by your run gps device and/or power meter when the workout is uploaded into WKO+ software. However, it can also be estimated by using a formula(TSS = Duration in hours x IF squared x 100) in and perceived rate of exertion scale devised by Andrew Coggan. This formula works equally well for the bike or the run and you can also use it to determine your TSS for swim workouts. You will notice on Joe Friel's blog that he makes special note of his TSS for each and every workout he places into his Twitter account. He is doing this in order to provide a better picture of what that workout meant to him in terms of duration and intensity.