Can I change the difficulty level during my training session?
According to your equipment, it's possible to change the global difficulty of the video from the app. If you have interactive equipment, you'll see a difficulty option with a '+' and '-' button: 
100% difficulty means the original difficulty is applied. You can change the difficulty from -50% to +50%.
For users having non-interactive equipment, this is what you'll see:
As we can't control the difficulty of your equipment, you have to apply the resistance percentage manually.