Xert FTP Tested
Xert Claims my FTP (Functional Threshold Power) Sits At 265 Watts. Is It Accurate?
I’ve always wondered if calculated Functional Threshold Power Values are accurate. Since 2017, however, I have relied on the Xert FTP value.
For years, we relied on the “20-Minute” Test. Riders would perform a 20-Minute effort, all out, and then subtract 5% from that value. The new number was considered “Threshold”.
Later, physiologists looked at 90% of a 3-Minute Maximal Effort.
There’s the 5-1-5 test….
Step Tests (25w steps every 3 minutes)…
Ramp tests (15-20w every minute)…
The latest ‘Testing’ asks for a 20-minute, 5-minute, 1-minute, and 5-second effort.
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Xert Claims that my FTP (Functional Threshold Power) is at 265 watts. Let’s find out how accurate that really is.[/caption]
NO MORE TESTING???.
Why We Still Look at Heart Rate
One of the old standards is Heart Rate. For decades, Heart Rate was a practical way to measure intensity. It could also be used to measure recovery, hydration, and fatigue.
We cannot look at wattage alone. We have to look at wattage as an extrinsic force. When we look at heart rate, this is an intrinsic force. Both bring value.
Here’s an example:
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Looking at Wattage and MPA only, this cyclist did not work too hard.[/caption]
This cyclist was given a workout of 60 minutes. The main set of intervals were 2 minutes long, with one at the end which was very intense and would hopefully yield a breakthrough per Xert.
If we look at the wattage chart alone, it shows a successful workout. MPA dropped, then rose, and the final interval yielded a CLOSE CALL, but not quite a breakthrough. Watts followed the load very closely.
However, when heart rate is revealed, it shows something more.