The Athletic Performance Curve

One of the most amazing things about humans (and all organisms really) is our ability to adapt. We are not robots with rigid body parts or hard-coded software. Our tissues are malleable and reactive, and our DNA provides our bodies with biological algorithms that can respond to a wide array of circumstances.

This adaptive capability is the core mechanism of fitness. In order to promote adaptation and improve fitness, we need to create the right physical conditions that will trigger the body’s adaptive processes.

But you can’t force or “confuse” the body to drive improvement. You must follow a logical program that progresses along the athletic performance curve to properly optimize the stress-recovery-adaptation cycle.

The Stress-Recovery-Adaptation Cycle

Inducing the body to adapt requires an “overload event” that pushes the body out of its comfort zone. The physical exertion required to produce an overload event varies depending on an athlete’s training focus and training level (beginner, intermediate or advanced).

For beginner athletes, the overload event is usually just an increase in stress from the last training session. For advanced athletes, however, the overload “event” is much more complex, and might actually be many events over the course of several weeks or even months.

When the body experiences an overload, its systems are stressed beyond anything that has been encountered before. The body needs time to recover from that stress. During this phase, food is broken down, energy stores are replenished, tissues are repaired and a myriad of other biological processes occur to bring the body back into homeostasis.

After the cycle is complete, the body is stronger and better prepared for the task. At this point, you produce another overload event at a slightly more stressful level than the last time, and the cycle starts all over again.


This is how the body adapts, and how you train to improve performance. Doing the same thing over and over will not produce any improvements. Too much stress, and you run the risk overtraining and exhaustion, which often leads to regression. So you need to achieve a fine balance with careful, precise athletic training.

Training at the Right Level

We’ve been using the terms beginner, intermediate and advanced. People usually associate these words with a certain level of ability, expertise, or skill.

But when it comes to athletic training and program design, ability or ultimate potential have nothing to do with the equation.

The key component is adaptive capacity.

Adaptive Capacity

Recall the stress-recovery-adaptation cycle discussed above, and how a beginner requires a relatively simple overload event compared to an advanced athlete who requires a more complex overload event.

This happens because, as an athlete becomes stronger, and their body becomes better adapted to a certain type of stress, it takes more and more stress to cause further adaptation. And as the body encounters these higher levels of stress, it also requires longer recovery periods.

What this means is that beginners actually have much more room to adapt, and they will be able to progress faster. Advanced athletes, on the other hand, have already progressed to a point where they are starting to approach their genetic limitations.

Training at the Wrong Level

If a beginner athlete attempts to follow an advanced program, one of two things will likely happen: 1) they will be overwhelmed by the training volume and intensity, and they will stall out and become exhausted; or 2) they will progress at a rate far below their potential and remain a beginner indefinitely.

Likewise, an advanced athlete who attempts to follow a beginner training program will either not be able to handle the rate of progression, or will not undergo enough stress to promote adaptation and improve their ability.

It is possible that a beginner can start out with higher athletic capacity than an advanced athlete because of innate genetic ability. However, a genetically gifted beginner cannot jump straight into a more advanced program to achieve superior results. They still have to start training at a beginning level and work their way up to optimally exploit their potential.

With these facts in mind, you can start to understand why achieving optimal fitness requires following a training program suited to each athlete’s level of experience. We can more easily visualize this by looking at the athletic performance curve.

The Athletic Performance Curve

The progression from beginner to intermediate to advanced, and the law of diminishing returns that governs this progression, follows a pattern found everywhere in the universe: the asymptotic curve. In the context of athletic training, we like to call this the “athletic performance curve.”


By looking at the beginner stage of the performance curve, you can see that the beginner has the most to gain and will experience the fastest improvement (assuming they follow an appropriate training program). Intermediate and advanced athletes encounter the law of diminishing returns – they have to work harder and harder to achieve smaller and smaller incremental gains.

Beginners can get more bang for the buck and improve faster than advanced athletes. Training athletes at a higher level before they are ready is a complete waste of time. Doing so ignores the body’s adaptive capacity and potentially leaves performance gains on the table.

Remember, advanced is not “better” than intermediate, nor is intermediate “better” than beginning. These classifications merely express where an athlete sits along the curve. And it allows us to choose an appropriate training program that will maximize the athlete’s progress.

The Differences Between Beginner, Intermediate, and Advanced

Ok, great. Athletes at different phases need to train at different levels. But what exactly does this look like? What does it mean that intermediate and advanced programs are more “complex?”

The meaning of “program complexity” varies somewhat from sport to sport, and even exercise to exercise. However, in general, complexity refers to the combination of volume, intensity, and recovery that make up a routine.

Let’s use strength training as an example.


Someone who has little or no experience lifting weights will begin by learning the movements. This is sometimes awkward and uncoordinated at first. But as the athlete practices, their nervous system adapts, and they start to recruit more muscles to perform the exercises.

In many cases, the first improvements in strength are mostly improvements in nervous system efficiency. In essence, your body gets better at using the muscles it already has in order to lift the bar. A beginner may not add much muscle at all and still get stronger, or they might add quite a bit. It mostly depends on genetics.

As an athlete progresses through the beginner phase, the body is able to adapt within a day or two. The weight on the bar is being increased every time (or almost every time), but the amount of weight is not so stressful that the athlete needs extensive recovery (though this may vary with genetics too).

Below is a graph that shows the training history of a hypothetical beginner. The red line shows the weight on the bar for each workout (intensity) and the blue line shows the total amount of weight lifted for the workout (volume, or weight × reps).

You’ll notice that the lifter starts out on a steady upward trajectory in terms of both intensity and volume. However, at one point, the total volume lifted starts to dip as the weight on the bar increases. After a couple dips in total volume, the routine is changed to introduce an active recovery day to allow for more recovery time. From there, the routine continues to increase the weight on the bar, but not in a straight line.

(By the way, don’t read too much into any of the graphs here. The rate of progression and the timeline used are for illustrative purposes only.)


Towards the end of the beginner phase, you’ll notice that additional complexity was introduced. The line between between beginner vs. intermediate, and intermediate vs. advanced is not necessarily clean cut.

Maybe we could draw the line where the intensity started to fluctuate, or maybe when volume started to dip. It doesn’t really matter.

The bottom line is that at some point the lifter could no longer progress at the same rate they were before. And this requires a change in the routine to account for the adaptations that occurred in their body.

The athlete is now stronger, and the level of stress required to create an overload event has increased. Additionally, the amount of time needed to recover has increased as well. Going forward, the routine will need to take these factors into account.

This next graph shows the routine of a hypothetical intermediate lifter.

You’ll notice that volume and intensity are now fluctuating from workout to workout. The relationship between the two variables has changed to create a more complex stress-recovery-adaptation cycle.


Once a lifter has progressed to the advanced phase, increases in performance are much harder to come by. Routines must be planned out with precision and discipline.

The advanced lifter does not achieve a personal record by chance.

Take a look at the graph below to see the progression of a hypothetical advanced lifter.

In this situation, the overload “event” is actually the entire first half of the routine. Next there was a recovery period where the lifter maintained high intensity for several weeks in a row, but kept volume low. Finally, after more than a month and a half of work, they were able to achieve a new PR. After that, they entered a deload period in preparation for the next cycle.


We used a strength training example here, but the same principles mostly hold true for any athletic endeavor.

As you can see, the training protocols are very different depending on the an athlete’s position along the athletic performance curve. If your program isn’t optimized for the body’s adaptive capacity, athletes won’t progress as well as they could.

Athletes must correctly train along the athletic performance curve to get optimal results.