Generally speaking, what sorts of split routines do you recommend to allow for the body to get adequate rest? I realize it has to be appropriate for the individual's schedules/goals. I know of two day splits (Day 1 - Chest/Shoulder/Triceps and Day 2 - Legs/Back/Biceps), upper/lower splits and two body part per day splits, but is the body affected in terms of strength and growth when the muscles are indirectly hit the day before?
I'm sure one would get a wide variety of responses to a question like this. The key is to separate opinions, beliefs, theories and gym science from the true sciences (i.e., biomechanices, physiology and nutrition as well as genetics and the client's goal).
Yes, there are many different types of "split routines," but without paying strict attention to the above mentioned "true sciences," the split that is ultimately chosen may wind up becoming more of a negative consequence than a positive one.
You virtually answered your own question when you stated: "I realize it has to be appropriate for the individual's schedules/goals." If the goal is post rehab, injury prevention, stability, coordination, power or improved overall performance, than the "traditional" training splits you are inquiring about would prove to be somewhat useless as they primarily focus on isolationist uniplaner exercises on artificially stabilized surfaces, with a goal of maximal hypertrophy only. In this day and age, with all the information available to fitness professionals, it must be universally understood that traditional hypertrophic goals make up only a small segment of a well balanced fitness/performance periodization plan and by no means qualify "fitness" (hence the old phrase "perceivably fit but unhealthy").
The following excerpt from "The Science of Loading" by Mitch Simon explains how one might determine the frequency of any given exercise program:
"How many workouts per week? Often the vicissitudes of life decide this question for us. Few of us are prepared to arrange our lives so that our primary focus is working out. Personal trainers can have a particularly tough time with this because the typical client will not surrender as much time per week for workouts as would, say, a college athlete. To make matters worse, that same typical client is often expecting a physical transformation of unlikely proportions - an elite physique in three hours a week! - within a time frame of three months or so. Good luck."
Digging in, we find five issues strongly influence (more like dictate!) our decision about how often to train.
- How much time per week the trainee can devote to exercise.
- The client/athlete's level of training. Effective workout schedules exist that call for six workouts per week for advanced trainees. Unfortunately "level of training" is hard to qualify. Considerations such as age, genetic endowment, concentration, exercise tolerance, activities of daily living, emotional stress, sleep habits (qualify and quantity), nutritional support, etc., as well as the quantifiable aspects of exercise history (e.g., time training, strength, skill, volume) all influence a person's "level of training."
- Intensity (percentage of one RM) of both the total workout (that is, the calculated average intensity of all the exercises in the workout) and individual exercises that may sufficiently tax a particular muscle group so that is requires extra rest. As we've said before, the more intense a workout is, the longer it takes to recover.
- The goal. Realistic goal setting is an important part of the client/trainer interaction. All kidding about clients wanting miracles aside, very often the trainee doesn't have enough information to set realistic goals. Once the trainer and trainee have set a goal together (beware of hidden agendas), then it can be broken down into long and short term goals with objective measures (e.g., a 10 percent strength increase in exercise within three months, ten pound loss of body fat in 30 days, etc). After these parameters have been set, it becomes easier to make an informed estimate of how many workouts a week are optimal.
- Soreness. If given adequate rest and nutritional support, our bodies tend to respond to the stress of working out by overshooting the pre-workout levels of metabolic substrates, biochemical cofactors, contractile proteins and other elements specific to the type of exercise performed, in a process known as super compensation. The new levels aren't permanent and will return to pre-workout levels if we don't exercise again in timely fashion (within a few days). If a client/athlete experiences delayed onset muscle soreness (DOMS) following a workout, it is by no means an indication of a good workout. In fact, if the soreness is enough to interfere with the workout we have a paradox. If the soreness is serious enough to cause a client to miss a workout, he will lose the super compensation. If soreness is serious enough to interfere with a workout and the client works out anyway, he risks injury and overtraining. Stretching to reduce DOMS has been shown to be ineffective and may even prolong soreness. Only two things reduce DOMS: anti-inflammatory and pain killing drugs AND performing the movements that caused the soreness at greatly reduced intensity. Take home message: Don't train clients in such a way that they become very sore. It's useless and self defeating.
I hope this helps in your decision process. Good luck.