When you start exercising, nearly anything you do will help you to get in better shape. If you were previously sedentary, taking walks in the park will improve your fitness. If you are used to hitting up the gym sporadically 1-2 times per week, then getting on a consistent schedule of 3x / week will help you to improve your fitness. For someone who is used to hitting the gym 3 days per week, 4 days per week may be the answer. However, with exercise, there is definitely a point of diminishing return with regards to the frequency and intensity of workouts. Once you become very fit you will be able to push your body hard enough, consistently enough, that recovery from workouts will be the main obstacle to progress. At this point you must scale back your workout volume, frequency or intensity to find where your work / recovery sweet spot is.
A good analogy for conceptualizing the idea of exercising diminishing return is to think about pouring water into a cup. When you tilt a water bottle to the side, water begins to flow out. If you tilt the water bottle over a little bit water will flow out rather slowly. You might notice that the water will be moving slowly, but very smoothly into the cup. After getting bored of watching the water move so slowly you might decide to tilt the water bottle over a little more. At this point the water will be pouring out more quickly. The water coming out of the bottle might be getting a little bit more choppy. Overall, the water should still be flowing smoothly into the cup. At this point you decide you have had enough with waiting for the water to come out so you tilt the bottle completely over until it is upside down. You now notice that the water is violently splashing out of the bottle. Instead of flowing smoothly into a cup the water is splashing out around the cup. Most of the water is either splashing around the cup and falling to the ground or causing some of the water in the cup to displace and splash over the side. You look at the water bottle completely empty and realize the horrible mistake you have made. You squish your feet in your now wet shoes and curse the gods for the cruel trick they have played on you. Because of your need for gains, I mean water, you have wasted what was a great bottle of water. This analogy represents what happens to someone when they up the volume, frequency, or intensity of their workouts beyond what they can recover from. when this happens the progress from their workouts will be lost just like the water that was supposed to be poured into the cup.
Continuing with the analogy, you should want the impact of your workouts on your body to be like the water pouring quickly and smoothly out of the bottle. You need balance in your frequency, intensity and volume. This is perhaps the main reason that cookie cutter programs are largely better than instinctive training for newbies. When you don’t have a clue about what your body can handle you are very likely to train too hard or not hard enough. Basically it is like someone trying to pour the water into a cup with a blindfold on and earplugs in. When you are relatively new to training your senses regarding what your body can and cannot handle are not well developed. Just to reiterate this does not mean everyone is out their overtraining. New trainees are just as likely to not push themselves hard enough. This is another reason coaching programs are an even better option than cookie cutter programs. While cookie cutter programs give you an idea of how hard normal people with normal lifestyles can push themselves, coaches can teach you how hard you can push on an individual level. Coaches can take into account your recovery ability, athletic background and lifestyle factors to design a program that allows you the fastest progress. This does not mean the fastest progress period, just the fastest progress that is reasonably sustainable given your unique circumstances.
I like the water bottle analogy because of its relevance to exercise in particular. It is such a great way to conceptualize your training. When you begin to make progress you definitely can speed up the progress by working harder. Anyone who has started a new program and really floored it can attest to this. You are working hard and killing it in the gym. All of your lifts are going up and you are looking better in the gym nearly every day. Everything is awesome and you are planning on staying the course indefinitely. Then you stall. You cannot get more reps or more weight and your body flattens out. For new trainees this could take quite a while, maybe 6 months. For experienced trainees, this often happens in 3 weeks or less on a new program. In order to continually make progress you must learn to moderate the different variables of exercise that will affect your recovery.
Many coaches have their own methods of moderating the intensity of workouts. One of the most popular fitness authors Mike Matthews advocates a controlled rep speed for new trainees. He uses a 2-1-2 rep speed, or 2 seconds lowering the weight, one second paused at the bottom and 2 seconds raising the weight. This type of rep speed forces the trainee to terminate a set when nearly absolute control of the weight is no longer possible. This prevents sloppy reps and pushing the body with weights beyond what it is capable of really controlling. Another popular fitness author Greg O’Gallagher advocates stopping the set a rep or 2 shy of failure. Never one to use light weights, this approach allows him to load up as heavy as possible without worrying about a breakdown in form. By emphasizing the weight as opposed to pumping out as many reps as possible, he is able to really push hard to get stronger without absolutely frying himself by also pushing for the max number of reps and sets. Though he advocates some seriously heavy weights for his trainees, his overall exercise approach is lower volume and frequency than most other authors. He advises trainees to use an average of 3 workouts per week with an average of just around 10 work sets per workout. An example of one of Greg’s workouts can be seen on Mike Matthews Muscle For Life site. Another great method for moderating workouts comes from the popular strength coach David Dellanave. David talks about using biofeedback with his clients to determine what exercises they will respond best to. Biofeedback is simply testing for a response from the body to determine how it will respond to different types of exercise. While he says their are many different methods of biofeedback that can be used, he recommends a simple stretch for most people. His stretch test allows him and his trainees to determine how beneficial or harmful different types of exercises, weights and rep schemes might be on any given day. By selecting the movements, weights and rep schemes that test best, his athletes are able to get more progress, with less of the deleterious effects that come from overtraining. Finally, Martin Berkhan discusses this idea of testing in one of his articles about learning when to back off on workouts. Martin says that because of his experience training, he can tell when he should back off. When he walks into the gym and notices the weight feels heavier than it should he knows it might be a day to back off. In one article he talks about setting up for a deadlift. After noticing that the plates he carried to the bar as well as his warm up sets were feeling heavy, he decided to cut his workout and walk out of the gym. While the advice about knowing when to pack it in is not as beneficial as something like testing for a new trainee, it lends credibility to the idea that their is definitely a point of diminishing returns. When guys as successful as the above four authors are all saying the same thing it definitely pays to listen.
If the above information makes sense, but leaves you wondering what to do, I would advise you to follow a training program to the T, hire a coach and follow their workout program to a T, or learn to cycle workouts yourself. Following a program to a T will allow you to gauge how your body responds to a certain style of training. After following a program for 6-12 weeks you will have at least a little bit of an idea about what a certain frequency, volume and intensity will do to your body. If you stick to enough programs for long enough you will gain a pretty solid understanding of how your body responds to different types of programs. When you work with a coach you will learn a tremendous amount about how you might be biasing your own training. By giving and receiving feedback about your workouts and thought process surrounding your workouts you accelerate your learning curve tremendously. You are able to learn where your point of diminishing returns is more quickly. A coach will unemotionally tell you if you are working too hard or not hard enough. A coach can easily tell you that “hey those extra sets of pull-ups and sprints are a waste and are hurting your progress” or “hey the programming is fine, if there is a problem it is with your intensity”. Finally learning to cycle your workouts is something most people will have to learn how to do in order to reach advanced levels of strength. Many authors talk about cycling intensity, but the basic concept is to cycle through phases of slightly higher volume or slightly higher intensity. This is simply to alter the stimulation the body is receiving slightly in order to make continued progress.
When starting any workout program your goals should be to progress, but also to continue learning about how your body responds to exercise. Continued learning in training is one of the best parts about exercise. You get better and better at determining your point of diminishing returns over time. Once you learn how your body responds its simply a matter of making small changes to your training in order to get slightly more progress over and over.