It's true, there were a lot of 60-90 min sessions sitting on an exercise bike. High intensity can work for lots of people, but depends quite heavily on your wei

It's true, there were a lot of 60-90 min sessions sitting on an exercise bike. High intensity can work for lots of people, but depends quite heavily on your weight / health condition. There's also a heightened risk of illness and injury if you're combining lots of high intensity training with a significant caloric deficit. I'd suggest talking to a PT and /or your doctor before jumping into doing high-intensity work if you haven't before.