Progressive Loading: A Better Way to Think About the Concept of Progressive Overload
Progressive overload, according to the National Strength and Conditioning Association (NSCA), is the principle of gradually increasing the demands placed on the body during exercise to stimulate further adaptations, such as increased strength or endurance. This can be achieved by increasing weight, repetitions, sets, or other training variables.
Progressive overload is crucial to resistance training for there to be improvements and adaptations, as the stimulus needs to progress over time in some form or fashion. Progressive overloading does not necessarily have to be increases in weight. It can also be manipulations or progressions in sets, reps, overall volume, velocity, and perceived fatigue/RPE (1).
Now, here is the big question I will attempt to address: does adaptation occur because you added weight/reps/sets and had to adapt to it (i.e. forced the adaptation), or did you adapt to the current stimulus over time where it is less stimulating than it was and now require increased stimulus to match your increased performance ability to continue to adapt?
I like the idea that Barbell Medicine has proposed where it’s more progressive loading vs overloading. Where you gradually progress the loading as your body adapts and indicates it needs increased loading vs forcing the overload. Plotkin et al provides an explanation that also aligns with this idea: “Maintaining a sufficient stimulus to match adaptive capacity is termed progressive overload. (1)
I think of it like this: you start with a stimulus that is relevant and appropriate to what you are after – strength, power, hypertrophy, etc. The weight, sets, reps, and effort should give you this stimulus. You stay with this, repeating the stimulus over and over again until the stimulus is no longer enough. This indicates you have adapted and are now in need of increased reps, weight, sets and/or effort to make the stimulus appropriate and stimulating again.
In order for progressive loading to be possible, it is necessary to adapt the body to the new effort provided by constant training because, without the adaptation phase, our body cannot continue to use a task that is superior to its possibilities. (2)
You don’t force the overload and adaption per se. You do need to start with an effective stimulus that is going to require you to adapt to a certain level of stress that is slightly beyond your current state, so in a way I suppose this is “forcing” to a degree. However from here you stay with this same weight/sets/reps/effort until this is no longer as stimulating (i.e easier), then you progress one of the variables from there. The stimulus may be enough stress and take longer than one training session/exposure for adaptation, so if you force and add progressions each session, you are doing so before you have adapted to the current stimulus. So the big difference is that you progress load or stimulus when there is indication that the current stimulus is no longer enough vs forcing the stimulus by increasing load each session or week regardless if your adaptation and performance indicates readiness for this.
Even in rehab, progressive loading is required as rehab is really training in the presence of injury and at some point the injury needs to be loaded progressively to facilitate recovery and return of function. In a rehab situation, the progression indication likely stars using pain levels and tolerance initially but will eventually progress towards more of a performance marker just the same as with training.
How do you know the training stimulus is not enough? How long do you stay with the same stimulus? You need some sort of metric(s) in your programming to indicate that you’ve progressed to a point where you need an increase in stimulus. Typically some variables will need to be held constant and 1 or 2 can be manipulated over time. Double progressions are currently my preferred way, where you progress both reps and weight over time. Double progressions will naturally progress load as your body adapts and demonstrates the need for increase in demand. As you get more adapted to the weight you will be able to perform more reps, and once you perform enough reps to reach a determined target, then you have demonstrated you are ready for progression of load. It’s a natural regulation and progression process that regulates to your state of performance each session and allows progression when it is appropriate and needed. The timeline for progression is naturally built in. I also like this as it incorporates both a progression of load AND reps, both of which have independently shown potential for improving strength and hypertrophy. (1) So you potentially are getting the best of both.
An example of double progression:
Pick a rep and set range, so we’ll say 10 reps and 2 sets
Then pick a weight: lets say roughly 75%, or a weight you think you could do around 6-8 reps and be 1-3 reps from failure with as a start point
You will do 2 sets with this weight doing as many reps as you can close to failure (you can determine how close to failure depending on you goals, etc but generally within 2-4 reps to failure. Once you achieve 10 reps for both sets, you have now demonstrated that you are stronger and need progression of load to meet your new strength level.
Now you will increase the load ~2-5% or 5-20ish pounds and repeat the process with the next weight.
You can also use RPE (rate of perceived exertion) as the indicator for progression with a set rep range where you would progress load if the RPE lowers (becomes less difficult) over time, indicating the need for increasing stimulus. The sets and reps are held constant, but the weight is progressed when the effort level (RPE) goes down. Here is an example of progression using RPE:
Pick a set and rep range, lets say 3 sets of 5
Now we determine how hard each set should be, using RPE (rate of perceived exertion),
Lets say we want the 3 sets to be an RPE of 7
We will start the first session by finding about where 5 reps at an RPE of 7 is for us.
We will repeat this weight again the next session for all 3 sets. If the RPE is the same or higher over the sets, we will repeat the weight again next session and potentially subsequent sessions until the RPE reduces. When the RPE becomes lower, indicating the weight is now easier, we will add ~5-10 pounds next session. So on and so forth
Linear progression programs work well for novice trainees and in certain rehab situations as the individual is relatively unadapted to the new stimulus, thus recovers and adapts quickly. Since they are unadapted or injured, they are going to start very conservatively compared to their potential, thus will look like they are making a lot of rapid, linear progress. In actuality, they are likely just progressing up to the appropriate stimulus initially, then are adapting further from there. They will typically be able to progress weight, reps, or sets nearly every session for a handful of weeks, but this is due to the quicker process of recovery and adaption to a novel stimulus as an unadapted trainee vs a forced progressive overload. They can adapt quickly and progress loading nearly each session. In rehab, there is likely a combination of detraining due to injury and starting at a very conservative start point, so the progress is going to look more rapid and linear since the start point was probably very far from their actual performance and capacity as the sensitivity and state of the injury is the limiting factor. However, the progress here is again due to a progression of loading due to quickly adapting in tolerance first, followed by strength/hypertrophy/power adaptations vs forcing the adaptations by progressive overload.
Forcing adaption via progressive overload by increasing reps, weight, or volume each session or week to week is not going to work for very long. The main reason is that you are likely not adapting that quickly, especially if you are not a novice trainee, thus the stimulus is increasing faster than you are adapting. You will potentially hit a wall very soon and could even develop pain issues or an injury in worst case scenario if the loading is increased too fast compared to what you are prepared to handle. You are trying to increase and force adaptations based off an arbitrary timeline vs realtime feedback that you have adapted and now need the progression.
Can you get stronger and/or improve hypertrophy lifting the same load over and over? Results from plotkin et al would suggest that yes, you can improve strength and hypertrophy by lifting the same load, however the reps need to progress. (1) There needs to be something that progresses for there to be progressive overload, thus if the weight stays the same, some other metric needs to progress to continuing increasing the stimulus. In this case, the volume or reps would be the progression.
Training has to be sufficiently stimulating to begin with and has to progress over time to facilitate continued and long-term adaptations. However, the progression needs to occur as you adapt and require more stimulus vs being forced at arbitrarily determined time points. Keep pace with the adaptations instead of trying to force them.
References:
Plotkin D, Coleman M, Van Every D, Maldonado J, Oberlin D, Israetel M, Feather J, Alto A, Vigotsky AD, Schoenfeld BJ. 2022. Progressive overload without progressing load? The effects of load or repetition progression on muscular adaptations. PeerJ 10:e14142 DOI 10.7717/peerj.14142
Geantă, Vlad Adrian, and Viorel Petru Ardelean. "Improving muscle size with Weider’s principle of progressive overload in non-performance athletes" Timisoara Physical Education and Rehabilitation Journal, vol. 14, no. 27, West University of Timisoara, 2021, pp. 27-32. https://doi.org/10.2478/tperj-2021-0011