Ramp Test with SmO2.pdf (407.0 KB)
This is my first use of the Humon during a ramp test to estimate my FTP or LT2. According to the TR-Ramp Test I did a week ago, it estimated my FTP at 205 W. So, I designed this ramp test beginning with 50 W (yellow), increasing every 4 minutes by 30 Watts.
I found it very interesting how SmO2 (blue) behaves. When the power steps up I see 2 phases:
Phase 1: in the initial phase a decline of SmO2, which is due to a higher demand on muscle oxygen in respect to an insufficient supply. Then,
Phase 2: the body reacts to the increased energy demands by raising blood flow to the muscles (e.g. capillary dilation) resulting in an increasing oxygen supply and a change of direction of SmO2, now going up.
This pattern is consistent for all steps except at 200 Watts. Here in phase 2, SmO2 does not go up, instead there is a further decline which means that the body cannot increase oxygen supply fast enough to cover energy demands. Around the middle of the interval, SmO2 stabilises, staying approximately constant until the end of the interval.
At the onset of the 220 W step there is a further drop of SmO2, even more pronounced following the 230 W step. This means that increasing energy demands, which cannot be supplied by oxidation (maxed out) alone have to come from glycolysis.
Summing up, I would assume that my anaerobic threshold (FTP, LT2, VT2) is around 200 Watts, because it is at this level that SmO2 does not increase (phase 2). It is the level that I could probably sustain, which is also colored green (sustainable) by the Humon App.
At the bottom you see the humon color zones: Green (steady state): when the oxygen delivery and consumption in the muscle is balanced, meaning the athlete is training at a sustainable pace.
Orange (approaching limit): when the muscle begins consuming more oxygen than what is being delivered, meaning the athlete is nearing their body’s limit.
I would say Orange (approaching limit) is already crossing the limit, so being conservative, II would rather use the “last” green step (200 W) as my FTP.
I am really amazed how well Humon works. It shows the actual zones while training. I did also an interval session which was also quite interesting, that I will show later.
I hope you guys find this as interesting as I do and I am looking forward to more insights using SmO2.