Hi all, I did attacker this morning and the distance displayed was about 8kms less than when I’ve done it previously. Average power wasn’t much different. Any ideas as to what might be happening? I’ve dialled down to 95% of my last tested numbers from March but the targets are still higher than this time last year which was calculated to be virtually further.
Virtual distance in SYSTM is an estimation at best. Won’t ever be precise. There ought to be fewer discrepancies provided you select virtual speed (rather than using a speed sensor or trainer speed) but even still, if will likely never be exact.
There’s more info here https://support.wahoofitness.com/hc/en-us/articles/4405896793490-Understanding-Virtual-Speed-in-the-SYSTM-app
but the bottom line is that SYSTM is not a real world simulator so I wouldn’t get too hung up on distance (or speed, or missing elevation) for the workouts.
One other suggestion is to check where the distance calc is coming from. 95% of the time my computer connects to virtual speed. The other 5% of the time it connects to the speed calculated by my bike. That is always 20-30% lower in distance. I catch it most times and change it but a few times I didn’t, and got that result.
One thing I will state is that the distance calculated by Virtual Distance is and always has been an approximation. It is never what you do on the bike. Same with Virtual Speed (and I can say that I was moving way slower on the Endurance rides than Virtual Speed gave me). The good part is that it shouldn’t have changed by the amount you state. I would look at your speed indicator (are you using Virtual Speed or the speed off of you wheel) and then look at the distance covered. I suspect you changed what you were using and now it appears off.
Thank you. I will check virtual speed. I didn’t get the power drop outs I have done in the past, but my phone bluetooth was turned off so maybe the signal wasn’t interfered with.