Various elliptical trainers enable exercisers to use preset programs to automatically vary incline, resistance and stride length over the course of a workout.
Whenever exercisers lift the head and upper body from the mat, they lengthen the back of the neck and nod the head forward, without jamming the chin into the chest.
For less resistance, an assisted dip/pull-up machine can be used which reduces the force necessary for the exerciser to elevate his body by use of a counterweight.
Compulsive exercisers will often schedule their lives around exercise just as those with eating disorders schedule their lives around eating (or not eating).
Anaerobic exercisers also have lower testosterone compared to the sedentary but a slight increase in basal testosterone with resistance training over time.