The most efficient way to incorporate exercise into your day is to make it part of your commute. Walking, biking, taking the train etc. - different modes are viable for different locations.
If you choose a job where this is not possible, you're just going to have to make it up some other way - two hours per week in a gym goes farther than most people think if you spend that time well.
In many cases at least one of these options is available to people but instead of taking it they whine that the job itself is too sedentary. I don't have a lot of sympathy, there are far worse jobs for the body than sitting in a chair (or standing stationary, your choice!) all day.
If truly none of these options are available to you in your current job - find a new one if you value your health. So many people have chosen a job for the money or prestige and just ignored this element completely. Those are unhappy people on account of their own choice.