A split workout is a type of workout routine in which a certain set of muscles worked on day one are rested on day two, while a different set of muscles are worked. On day three, the original set of muscles can be worked again. The idea behind a split workout is to keep the workout program going steadily while allowing certain muscles to rest sufficiently enough to be worked again later on in the week. Critics of the split workout contend that it does not allow the person exercising to excel beyond a certain point of fitness, while supporters argue the workout allows the body to recover more effectively, and it allows an exerciser to isolate certain muscle groups for development.
The most common split workouts are upper/lower splits, in which the upper body muscles are worked on one day, and the lower body muscles are worked the next workout day. Other split workouts exist, such as push/pull workouts, in which exercises that require the exerciser to push are done on day one, and exercises that require pulling are done on the next workout day. An example of an upper/lower split workout looks something like this:
Day One: chest, back, biceps and shoulders
Day Two: quads, hamstrings, calves, and abs
Day Three: rest day
Day Four: chest, back, biceps, and shoulders
Day Five: quads, hamstrings, calves, and abs
Day Six and Seven: rest days
Each day focuses on a set of muscles that typically work together. While working one's chest, for example, he or she may end up working the biceps and shoulders as a secondary exercise. The same goes for exercises that work the biceps: the chest and shoulders may end up being used during the exercise. The split workout is essentially the opposite of the full body workout, in which one would work all muscle groups in one workout, then repeat the workout again on a subsequent workout day.
Other advantages to the split workout routine include time savings. A typical split workout will take about 45 minutes at the gym, usually spent lifting weights. A full body workout can take up to two hours to complete, so a split workout can work out much better for people with difficult schedules that don't allow them much time at the gym daily. Split workouts are also usually higher intensity workouts since less time is spent at the gym, meaning muscle mass can be gained more quickly than it can be during a full body workout.