Are you in Canada? Click here to proceed to the HK Canada website.

For all other locations, click here to continue to the HK US website.

Human Kinetics Logo

Purchase Courses or Access Digital Products

If you are looking to purchase online videos, online courses or to access previously purchased digital products please press continue.

Mare Nostrum Logo

Purchase Print Products or eBooks

Human Kinetics print books and eBooks are now distributed by Mare Nostrum, throughout the UK, Europe, Africa and Middle East, delivered to you from their warehouse. Please visit our new UK website to purchase Human Kinetics printed or eBooks.

Feedback Icon Feedback Get $15 Off

Human Kinetics is moving to summer hours. Starting May 31 – August 2, our hours will be Mon – Thurs, 7am – 5pm CDT. Orders placed on Friday with digital products/online courses will be processed immediately. Orders with physical products will be processed on the next business day.

Defining and Understanding Strength Training Load Progression

This is an excerpt from Periodization Training for Sports-3rd Edition by Tudor Bompa & Carlo Buzzichelli.

Defining and Understanding Strength Training Load Progression

Progressive overload is the favorite modality for eliciting morpho-functional adaptations through a progressive increase of muscular, metabolic, or neural stress over time. There are many ways to rationally progress the load and thereby elicit the desired adaptations, such as higher levels of hypertrophy, muscular endurance, maximum strength, or power. In order to understand these options, we must analyze the loading variables and how they influence the final training effect.

In the case of strength training, the training parameters are shown in figure 7.11.

Figure 7.11 Strength training parameters.
Strength training parameters.

Throughout a macrocycle, we can progress one or more of these parameters according to the training effects (adaptations) that we want to elicit. The parameters are described in detail in the following sections.


The number of repetitions per set is very much linked to the percentage of 1-repetition maximum (1RM) used and the desired buffer (the difference between the number of repetitions performed in a set and the number that the athlete could perform to exhaustion at that percentage of 1RM). Throughout a macrocycle, we can either increase repetitions in order to increase endurance (more volume), keep repetitions the same while manipulating other parameters, or decrease repetitions to increase intensity (percentage of 1RM) or to unload or peak while maintaining or slightly reducing the intensity. In the latter two cases, we unload by increasing the buffer.

Throughout a macrocycle, we can decrease the buffer while maintaining the same number of repetitions. Doing so makes each workout progressively harder, while maintaining the same number of sets and reps (a preferred method by powerlifters that can also be used in other sports). We can also keep the buffer the same while increasing or decreasing one of the other parameters. Usually, we do not increase the buffer throughout a macrocycle, unless we are transitioning from a maximum-strength development macrocycle to a maximum-strength maintenance or a power macrocycle.

A high buffer allows for performing more technically correct repetitions because the load is less challenging, more explosive concentrics, and reduced residual fatigue. Thus high-buffer sets are used especially for intermuscular coordination work, for power development, and for unloading microcycles (see table 7.1). Buffer 0 means going to concentric failure, a preferred modality for hypertrophy training. Doing multiple 1 to 3 reps per set to failure or close to failure (5 percent buffer) elicits gains in relative strength that is an increase of strength without an accompanying increase of body weight. Going to failure or getting close to failure with a slightly higher time under tension per set and performing 3 to 6 reps will elicit gains in absolute strength that are gains in both strength and muscle size. Performing sets of 1 to 3 reps with a buffer of 10 to 20 percent will increase both maximum strength and power (what some call the "strength-speed method"). Performing 3 to 6 reps with a buffer of 25 to 40 percent will increase both maximum strength, via an improvement of the intermuscular coordination, and power (what some call the "speed-strength method"). We believe that terms such as strength-speed and speed-strength should be replaced by power training with high loads and power training with low loads, because in physics we have power, not strength-speed or speed-strength.


Throughout a macrocycle, we can increase sets in order to increase work capacity and endurance (more volume). We can also keep the same number of sets to increase one of the other parameters or decrease the number of sets to unload or peak. The number of sets (volume) is the single most influential variable the on training's residual fatigue effect.


Tempo is the duration of a full rep; therefore, it affects set duration. In turn, both the tempo of a single rep and the set duration directly influence the final training effect. For this reason, once the desired training effect and the corresponding rep tempo and set duration are established, it is advisable to keep them stable throughout the macrocycle. Changing them - for example, by performing the repetitions faster - might give the false impression of progressing when in fact the training effect is changed. Tempo is indicated with three or four numbers. The first number depicts the duration in seconds of the eccentric phase; the second number depicts the pause between eccentric and concentric; the third number depicts the duration of the concentric phase (an X means explosive); and the fourth number depicts the pause between the concentric and eccentric phase. For example, 3.1.X.0 for a squat means a descent of three seconds, followed by a pause of one second, followed by an explosive ascent and no pause before descending again.

Rest Interval

Like tempo and set duration, the rest interval directly influences the final training effect. We can increase the rest interval if the macrocycle moves toward a decrease in reps and an increase in intensity (percentage of 1RM). We can decrease the rest interval in order to increase endurance (more density). Or we can keep the rest interval the same while changing one or more of the other variables. When performing series of sets for power endurance and muscle endurance, reducing the rest interval between sets (while maintaining their power output) allows a densification that later translates into a higher mean power output for a longer duration.

Technique should also be considered; indeed, it should never be sacrificed for the sake of a false load progression. As Paul Chek has said, changing technique to grind out more reps or complete a heavy one is just "the world's fastest superset" - a potentially injurious and certainly deceiving action.

For an example of progression in parameters, see the program for the junior soccer player in the previous chapter (law 4).

Learn more about Periodization Training for Sports, Third Edition.

More Excerpts From Periodization Training for Sports 3rd Edition