As we know everyone have their own native cadence. Even in pro peloton, different riders have different comfortable cadence, some stay most of the time at as low as 80rpm, while others can keep it at up to 110rpm and feel just great.
For me, comfortable cadence, which I can sustain without any issues for 370km ride with an average 2.8w/kg or for one hour race with an average of 3,8w/kg is 80-85rpm. At races I can sustain 95rpm in long sprints and on very short sprints I can spin at 105rpm. (I took data from real word rides and races in zwift using wahoo kickr 15 with wahoo cadence sensor).
ERG mode is where the problem start to occur.
I will take as an example “4wk FTP Booster - Week 1 - Day 2” program.
It asks a rider with a ftp of 4w/kg to keep 7.1w/kg at 100rpm for 45sec, 6 times with some rest in between. For instance this would be more than okay for me at cadence 95, but zwift forces any rider to keep it at 100rpm, which is overkill for me, and instead of concentrating on power output I am forced to grind thru resistance to rise the cadence again and again.
In ERG mode to get to required cadence the rider needs to break thru current resistance, which basically means put more power than it is set to and face such issues as constant resistance drops and rises while smart trainer is trying to adjust itself. This heavy “spin faster” grinding reminds of pedaling in mud but at quite high power output. That easily can lead to injury in knee joints.
I offer to add the line for target average cadence somewhere near the ftp/weight/maxhr in profile settings, so each workout program will adjust required cadence accordingly to this number. So if your comfy cadence is 95, all the cadence requirements in a workout will be raised by 5.
This number can be picked up from the existing “ftp test“ by default, and should be opened to be set manually if the rider wants to increase his comfy cadence (low cadence is a usual thing for a beginner).
ps. some of people I know experience the same problem as I do because their comfy cadence is lower than default and some other guys always find the same workouts as “very nice and silky smooth”, but their comfy cadence is 95rpm.
pps. sorry for my English