THE SQUAT. It seems that people either love this exercise or hate it. If you hate doing squats, then you need to learn to love them. There is probably no other exercise that has a greater impact on your body's muscle, metabolism and energy expenditure. Why? Because the squat is a complete-body movement exercise. This means your legs (especially quads, hamstrings and glutes), abdominals, lower back, arms and shoulders are targeted.
I would recommend doing squats without machines or weight belts. This will force you to learn how to stabilize your body without artificial support. If you are not able to perform squats with barbell or dumbbell weights because of injury, then start with body-weight squats. Either way, don't exercise without doing squats.