Just entered the Zwift world a few weeks ago to supplement my running. I think everything is setup correctly with my FTP and HR for cycling. My question is are Zwift load numbers realistic or is the Intervals algorithm assuming it’s and outdoor ride? My Zwift speeds are much higher than outside so I question if the load is accurate?
How are you measuring load? Assuming power as you mention FTP.
What trainer are you using? A smart power based, or a non-smart trainer that uses speed and cadence.
The speed on Zwift, if you’re in a bunch will be faster than if you ride on your own. You do get a drafting benefit.
I bought the Zwift Ride with a Wahoo Kickr
So assuming your FTP is (relatively) correct, then the load will be (mostly) correct; it isn’t influenced by the speed. Weight can play a part on the gradients, if you’re “under weight”.
If Power is recorded, Intervals will calculate load based on power relative to FTP. This is not dependent on the Zwift Load, but should be very similar if your FTP is set at the same value on both platforms.
Thanks. That is good news.
I did a FTP test on the Zwift app so it should be fairly accurate. My weight is correct, so I’m not weight doping lol 
It’s not as simple as doing a test, but is close enough to be used. Have fun “zwifting”