According to the American College of Sports Medicine, the progressive overload principle states that to enhance muscular fitness, you must exercise at a level beyond the point to which your muscles are accustomed. In other words, if it doesn’t challenge you, it doesn’t change you.
It is the concept through which human performance parameters can be continuously improved. Granted, progression will eventually lead to diminishing returns, and certainly, you cannot continue to improve forever. However, understanding progressive overload will help you maximize your improvements over time.
A misnomer of sorts
There is a problem with progressive overload, unfortunately, and that problem lies in its name. Using the word progressive was an excellent choice to describe the continuous nature of improvement, but the word overload is misleading.
The word overload in the phrase is not exclusive to resistance. Instead, it’s in reference to an overload of stimulus. The misunderstanding of the phrase, itself, appears to be at least partially responsible for the belief that increasing exercise resistance is the only way (or at least the most rapid way) to grow muscles; this belief is untrue!
Heavier resistance does not mean larger muscle growth, and progressive overload does not simply mean increasing the resistance of your exercises.
What does it really mean?
Progressive overload is a theme across all forms of exercise. The phrase is in reference to progressively challenging your body to adapt. Unfortunately, as previously mentioned, the word overload is often misleading. The phrase might be more appropriate as “progressive challenge.”
If your goal is to build muscle mass, heavy resistance is not the only way to achieve this goal. In fact, in some instances, heavy resistance is not a factor, at all.
To outline all the possible challenges you can make within the scope of progressive overload, we use the FIT Principle:
Frequency: for exercise protocols, frequency overlaps with training volume describing how much exercise you are actually performing
Intensity: how hard you are working; resistance falls within this category, but intensity also describes effort/exertion and includes utilizing power (force * velocity, more on this below)
Timing: self-explanatory; includes repetition cadence and rest interval timing.
Frequency
For progressive overload, frequency is actually the most dynamic variable. There are four main ways to vary the frequency of your training: repetitions, sets, exercises, and workout sessions.
Repetitions per set: often, you’ll hear reference ranges for repetitions per set around 6-15, depending on your goals. With heavier resistance, repetition range is generally lower (5-8), where lighter resistance would normally demand a higher repetition count, per set (10-15). However, research has suggested higher repetition ranges (e.g., 30 or more) can still elicit similar muscle growth as lower repetition ranges.
Sets per exercise: many people perform 3 sets of a particular exercise before moving to a different one. However, if you feel like your routine is no longer benefitting you, adding additional sets per exercise is an option to create a more challenging environment for your muscles. Likewise, if you’re training to concentric* failure or absolute failure (defined here), it may be prudent to perform a lower number of sets (2-3).
Exercises per workout session: in Art of Anatomy, many of the exercise programs are based on training ranges where you will need to perform at least one exercise per training range. For muscles like the calves, there are fewer options based on limited movement capability; thus, you may only perform one or two exercises in one workout. For muscles like the deltoids, however—an incredibly dynamic muscle with enormous movement capability—you may perform 6-8 exercises in one session.
Workout sessions per week: while the risk for overtraining exists with increasing any of the previous three factors, the risk is even greater if you are not careful with how many exercise sessions you perform, for the same muscle, within the same week. Generally, it is never recommended to train the same muscle (or group) more than twice in one week*, and you should never train a muscle that is already sore from a previous training session.
*It is a myth that certain muscles (e.g., abdominals or calves) can be trained every day. This will lead to overtraining and may cause injury.
There are three ways to vary the intensity of resistance training within progressive overload: the resistance, itself; utilizing power; and effort/exertion.
Resistance: resistance is simply how much weight you are attempting to move for a selected workout, and increasing resistance will increase intensity. Unfortunately, many people think about resistance, alone, when discussing progressive overload. However, resistance is just one single factor, and it is not the most important factor for muscle growth!
Repetition tempo: The eccentric phase of the repetition should not vary; however, increasing or decreasing the velocity of the concentric phase will alter the intensity of the exercise. Increasing the velocity increases power, which can help to recruit more type-II muscle fibers.
As a performance metric, power is defined as the force multiplied by the velocity (or work over time). For example, bench pressing 135lbs with a 2-second concentric phase is less intense than bench pressing the same 135lbs with a 1-second concentric phase. You will learn more about utilizing power in the Repetition Performance page of Program Design (coming soon; sign up for email updates!). To simplify and separate power from repetition cadence, utilizing power would be performing the concentric phase as quickly as possible.
Effort/exertion: for resistance training, effort/exertion is described by your fatigue or failure of a particular set (or across multiple sets) of exercise. Common references for effort/exertion include volitional fatigue, repetitions in reserve, concentric failure, and absolute failure.
Effort/exertion
Effort/exertion can be described in many ways, and there are certainly more than the examples described below. For the purpose of Art of Anatomy, there are four categories of effort/exertion you can use in your training. The four factors are listed from least to most intense.
Repetitions in reserve: this technique is when you stop your set (x) amount of repetitions before you reach expected failure. This is usually a strategy for higher volume training (e.g., planning to complete more sets). Repetitions in reserve is more calculated than volitional fatigue; you will often stop 1-3 repetitions before expected failure.
Volitional fatigue: choosing to end an exercise because you have reached a level of fatigue beyond which you don’t want to push; this is not equivalent to failure. This is often a strategy used when you are training without a spotter and performing exercises where failure may become dangerous (e.g., bench press where the bar can fall onto your chest).
Concentric failure: the inability to shorten the target muscle against resistance. For exercises such as the bench press and squat, this means failing to push the weight upwards. For a lat pulldown, it would be a failure to pull the weight downwards. In both cases, you will likely still have eccentric control (e.g., being able to control the weight in the down-phase for bench press). If you plan to train to concentric failure on exercises where the weight is on top of you, you must have a spotter for safety! Concentric failure is high-intensity training. If you’re choosing this intensity, your training volume must be lower.
Absolute failure: this technique requires a spotter for both safety and completion of the target exercise. Different than concentric failure, absolute failure is when you’ve eclipsed concentric failure and can no longer control the resistance in the eccentric phase (e.g., lowering the weight under control for bench press). Absolute failure is the highest intensity form of training, it must be performed with a spotter, and it demands lower training volume.
There are two factors of progressive overload that involve timing in your resistance training routine: repetition cadence and rest intervals.
Rest intervals: this is how much time you rest between individual sets of exercises, and this timing will vary based on other factors of your training. For example, heavier resistance and/or higher-intensity training will require longer rest intervals (3-5 minutes); likewise, lighter resistance and/or lower-intensity training may favor shorter rest intervals (1-2 minutes).
Progressive overload is not specifically about increasing the resistance (or load). Rather, progressive overload is a simple notion:
If the exercise (or routine) becomes easy, change one of the factors above to make the exercise more challenging.
If you’re training chest once per week using the bench press—performing 3 sets of 10 repetitions, a 3-second repetition cadence, 135lbs of resistance, stopping at volitional fatigue, and using a 2-minute rest interval—and it is no longer challenging, here are a few sample changes you can make to your routine. Below are the nine factors; you only need to change one factor at a time!
Frequency
Sets: perform an additional set or two
Repetitions: perform additional repetitions (e.g., 12-15 each set)
Exercises: add an additional exercise (e.g., dumbbell flies)
Sessions: perform the same routine twice per week instead of once
Intensity
Resistance: increase the resistance (e.g., 145lbs)
Repetition temp: perform the concentric phase with a greater velocity
Effort/exertion: bring a spotter and exercise to concentric failure
Timing
Rest intervals: shorten the rest intervals to 60 seconds
Challenge for change
For all living organisms, there is a universal truth that can be identified simply as the SAID principle: Specific Adaptation to an Imposed Demand. This principle is simple and straight forward; living organisms will attempt to change (adapt) to survive in their environment (imposed demand). Thus, progressive overload dictates a pattern for change.
Ultimately, your body will attempt to adapt to any demand you place on it, and exercise includes various types of physical demands. Training with volume and/or resistance are demands to which your body will adapt; the most common and desirable adaptation to these demands is an increase in muscle fiber size (hypertrophy). This adaptation is a protective mechanism for your muscles to prevent injury.
For progressive overload, it’s through the SAID principle that we adopt the phrase, if it doesn’t challenge you, it doesn’t change you.
This phrase is the safe, more appropriate alternative to the old-school “no pain, no gain,” which is dangerous and promotes an unhealthy attitude towards exercise. Exercise should never be painful. You may experience burning fatigue and occasional cramping, but the performance of exercise should not be painful. If you experience pain during exercise, stop what you’re doing and contact your doctor.
Strength ≠ mass
This misconception is still too common and often perpetuated by uneducated fitness influencers, poorly educated certified personal trainers, and every day gym-goers. Many people continue to claim and/or believe that lifting heavy is the only way to grow muscle—a clear misunderstanding of progressive overload.
While adding resistance is certainly a valuable factor in achieving muscle growth, adding too much resistance can be counter-productive and may also increase your risk for various injuries including muscle strains, joint or ligament sprains, or worse.
Concentric: when a muscle becomes shorter while under tension, it is described as a concentric contraction. Examples of concentric contractions are all the “up-phases” of your exercises—the up-phase of a bench press, squat, deadlift, biceps curl, etc. For exercises such as the lat pulldown, the concentric phase is pulling the handle downwards.
Eccentric: when a muscle becomes longer under resistance while controlling a joint movement, it is described as an eccentric contraction. Examples of eccentric contractions are all the “down-phases” of your exercises—lowering the weight to your chest on a bench press, the down-phase of a squat or deadlift, lowering a weight back towards your hip in a biceps curl, etc. For exercises such as the lat pulldown, the eccentric phase is controlling the handle on its way upwards.
