Dieting, meds, different programs and power.
Has anyone any similar experiences of a greatly differing FTP using different programs? I'm on a high protein, low carb diet at the moment and appreciate that low carbs isn't ideal for prolonged high end efforts, but didn't expect a drop of 14 watts! My previous FTPs have been with TTS4 and their CP20 and the Zwift CP20 test, both with similar results. The last test was about 6 weeks ago and have been pushing hard in between. A drop in power was not expected, especially when combined with the weight loss. I'm on statins for a left subclavian occlusion, so my heart rate rises rapidly and stays there, but my legs don't suffer as a consequence.
I ride a bike. Doesn't make me green or a tree hugger. I drive a car too.