What type of fitness testing works best: FTP or LT testing? Or is more info needed?
Shannon Grady of Go Athletics responds:
Cyclists / triathletes ask me this question often. The two metrics are comparable to one another but also comparably deficient, and thus ineffective training indicators. Neither FTP nor Lactate Threshold testing tells you the “what”, “why”, or “how.” In other words, “what” type of energy an athlete has available to perform work/training/racing; “why” the athlete may or may not be improving his/her FTP, LT, or performances; and “how” to the athlete should steer his/her training to improve physiology for better performances.
FTP is an arbitrary metric, and serves as a proxy for only one type of effort. Using % of FTP values as a benchmark for training will, as a result, over work some and under work others. “Lactate threshold” (LT) values can be similar to an FTP value, but similar to FTP, it is a one-dimensional view of performance. Comprehensive blood testing (of which lactate threshold is a component) opens the doors to dynamic analysis on how all energy systems are performing (not just one energy system like FTP/LT), each of which are critically important in determining successful performance. Looking at either FTP or LT in a silo will give you a misinformed view of the truth.
Instead, I use (and recommend you use) a physiological profile test (PPT), which uses lactate but is not a lactate threshold test. This kind of test gives a more complete picture of the entire energy spectrum, and enables coaches and athletes to understand the “what,” “why,” and “how.” As a result, the coach or athlete can have more insight into the training stimulus required to improve both the metabolic outputs and performance of each athlete.
Below is an example of two cyclists PPT results (who I recently tested), both of whom have the same FTP values. Despite having the same FTP values, Cyclist #2 is operating off more bioenergetic availability than Cyclist #1.
Cyclist #1
Cyclist #2
Even though both have the same FTP value, they arrive at this value using different energy sources. Cyclist #1 will have a negative metabolic response and performance outcome if he trains at the same FTP % values as Cyclist #2 because their actual energy contributions when performing work at the same percentage of FTP are about 25% different. In summary, FTP or LT is too one-dimensional to extrapolate usage across various energy systems because it assumes all athletes have the same functional work capacity. This is not true given that the physiological blueprint for all athletes are extremely unique, and will cause athletes to under-optimize the needed training stimulus. Physiological profile testing will better pinpoint functionality across all energy systems and be specific to each athlete.
Shannon Grady. Physiologist. CEO/Founder Go Athletics. Coach/Consultant to Pros, Olympians, NCAA Champions, HS and Recreational coaches and athletes. 5x TeamUSA member, Ex-Pro Runner, NCAA All-American, now enabling others to achieve their potential.