Flexible Non-linear Periodization: Keeping Your Options Opened

Non-linear periodization is a topic I have covered many of times in past blog articles.  I have looked at research and given some practical applications of how to use this sort of periodization structure.  Just to review, linear periodization begins with low-intensity/high volume lifting and progresses to high-intensity/low volume lifting over the course of many weeks.  For example:

  • Week 1-3: 3×10
  • Week 4-6: 3×8
  • Week 8-10: 4×5
  • Week 11-12: 6×3

While non-linear periodization allows for weekly or daily fluctuations of training volume and intensity.

A weekly non-linear periodization example:

  • Week 1-2: 3×10
  • Week 3-4: 4×5
  • Week 6-8: 3×8
  • Week 9-10: 6×3

A daily non-linear periodization model example:

  • Day 1: 4×4
  • Day 2: 3×8
  • Day 3: 3×10

Flexible Non-Linear Periodization

A recent study published in the Journal of Strength and Conditioning Research actually looked at the concept of flexible non-linear periodization.

What this basically means is that you have the freedom to alter the workout based on how the athlete (or yourself) is feeling on any given day.  There are various ways to determine when to change the workout, and I will address some of these below.  But in a nutshell, this concept allows you to take into consideration the individual and make the program more specific to them.

Training programs are really nothing more than a shell or outline of what needs to take place.  The program should, however, be plastic and allow for changes depending on the individuals progress (progressing quicker or slower than expected), competition schedule (a competition may come up in the middle of a training cycle, or the athlete may decide to jump into a competition at the last second that was not on their original competition schedule), or based on how the athlete feels (tired, beat down, getting over being sick, etc.).

The study conducted by McNamara and Stearne sought out to determine the effectiveness of flexible non-linear periodization when compared to regular non-linear periodization.

The subjects were placed into two training groups for the entire 16-week cycle:

  • A non-linear periodization group who alternated workouts between 10-reps per set, 15-reps per set and 20-reps per set.
  • A flexible non-linear periodization group who used the same repetition numbers; however, this group was allowed to pick between which repetition number they performed for a given workout.  This choice was based on the subjects rating their energy levels (a scale of 0 to 10, which 0 being “no energy” and 10 being “extremely motivated and full of energy”).  In order to ensure that the subjects in both groups performed the same total volume for the entire study, the subjects in this group were allowed to choose their rep number, however they had to choose one of the other two rep numbers in the next workout, so that one rep number was not prioritized over another.  Because of this, towards the end of each 4-week mesocycle, it was possible that the subjects were not given a choice of which rep range to choose, in order to keep total volume between groups similar.

The subjects trained twice a week for 30min. each session.

Pre and post tests consisted of leg press, chest press and standing long jump.


The flexible non-linear periodization group improved significantly in the leg press, while changes in the standing long jump and chest press were not significant between the two groups.

The researchers stated that the superior improvements in leg press by the flexible non-linear group may be attributed to the subjects having the ability to choose between rep numbers for each workout, allowing them greater recovery between sessions, and thus greater improvements in strength.

The insignificant improvements in long jump may be attributed to the fact that the subjects performed no power training during the 16-week training program, and the training program in this study consisted of repetitions that were low in velocity.  Thus there was no stimulus to adequately improve this quality.  The lack of significant difference between the two groups in the chest press may be due to the fact that the upper body received more overall training volume, a greater number of exercises, than the lower body, leading the researchers to believe that the upper body may have been overtrained.

The researchers concluded that, “A flexible non-linear periodization program may be a highly effective method of training for improving leg strength.  Coaches can immediately implement a flexible non-linear program by evaluating the readiness of an athlete immediately before his or her training session, then adjusting the assigned exercise intensity accordingly.”

My thoughts on using this practically

While a flexible approach to periodization is certainly nothing new, this is the first study (that I am aware 0f) that actually looked at the difference between a non-linear and a flexible non-linear training program.

In Supertraining, Mel Siff, actually talks about the concept of cybernetic periodization, which he discusses in regards to the training of the Bulgarian Weightlifting Team.  Basically, instead of being stuck in a very rigid periodization program, where you are forced to stay true to whatever lifting percentage is prescribed for the day, Mel advocates adjusting the daily lifting percentage based on subjective and objective feedback obtained by the lifters performance.  From there, the lifter trains on a rate of precieved exertion.  If things feel heavy that day or the athlete does not feel strong, then the training load is lighter, and vice versa.

This concept is not a bad idea, as it allows you to ensure that the athlete is fully recovered before performing high quality work.  The 0 to 10 scale in the study should not be the only way to obtain information on the athlete.  Obviously lazy athletes or athletes who like to go out and party and drink at night, will constantly be reporting low numbers so that they can slide by with easier workouts (but, you should really talk to the athletes about their all nighters and party habits, as this can be a real problem with their preparation).  On the flip side of that, highly motivated athletes that never want to give in to having a light workout will always report high numbers so that they can always train harder.

In Optimizing Strength Training: Designing Nonlinear Periodization Workouts Kraemer and Fleck advocate testing the athlete with a power exercise – like a vertical jump – to determine if the athlete is prepared for intense training (either power or intense strength work) that day.  If the power exercise is near their normal pre-training numbers (within 10%) then they are cleared to go, if it is outside of that 10%, then you need to divert to a less intense, more recovery focused workout.

Obviously other tests could be performed in a addition to or instead of the power exercise, to gain more feedback on the athlete.  Some coaches may use things like blood pressure, resting/waking heart rate, and others have talked about using Heart-Rate Variability as measures of an athlete’s preparedness to train.

One of the issues with the study above is that it was conducted on subjects who were new to resistance training, so it is difficult to tell whether or not this type of flexibility will be successful in elite athletes.


It appears that flexible non-linear periodization may be helpful in the preparation of athletes, as it allows for individual variability in recovery from training and competition.  No two athletes are alike, and one may have better recovery from a training program than another.  Because of this, coaches need to monitor their athletes to ensure that they are getting the most out of their training program and recovering adequately, to prevent overtraining and decreased performance.


McNamara JM, Stearne DJ. Flexible Nonlinear Periodization In A Begginer College Weight Training Class. J Strength Cond Res2010;24(1):17-22.

Siff M. Supertraining. Supertraining Institute; 6th ed. 2003. pgs. 326-327.

Kraemer WJ, Fleck SJ. Optimizing Strength Training: Designing Nonlinear Periodization Workouts. Human Kinetics. 2007.