Mass Research (Volume 1 - Issue 1)
Daily undulating periodization (DUP), the practice of altering repetitions or training focus (hypertrophy, strength, or power) each session, has increased in popularity in recent years. However, when the prescribed repetition schemes are performed in a fixed order throughout the week, the resulting rigidity may not accommodate fluctuations in the athlete’s readiness, so it may be beneficial to incorporate some form of autoregulation within a DUP model. This study compared a flexible DUP (FDUP, n=14) strategy against a fixed DUP (n=11) weekly strategy to test this hypothesis with trained males. The FDUP lifters could choose which daily training session they wanted to do (hypertrophy, strength, or power) based upon their daily readiness, with the stipulation that each of the three sessions must be performed within each week. The DUP group performed training in the fixed weekly order of hypertrophy (Monday), power (Wednesday), and strength (Friday). The training programs lasted 9 weeks, and squat, bench press, and deadlift 1RMs, along with Wilks Score (relative strength) were tested before and after the 9 weeks. Further, total volume and repetitions performed were compared between groups.
Both groups had significant increases (p<0.05) in both absolute and relative strength for all individual lifts and powerlifting total (FDUP: +9.3% and DUP: +9.2%) over the 9 weeks, but there were no differences between groups for any strength measure (p>0.05). Additionally, there were no group differences in training volume or repetitions (p>0.05). Interestingly, there was possibly slightly greater adherence to training in favor of FDUP. Importantly, FDUP produced similar adaptations in trained males to a fixed weekly order DUP configuration of hypertrophy, strength, and then power over 9 weeks.
The purpose of this study was to compare the effects of 9 weeks of DUP versus FDUP (i.e. flexible order of weekly training sessions) training on training volume and absolute and relative strength in the powerlifts and powerlifting total. A secondary aim was to assess if there were any differences between satisfaction of training sessions, rating of perceived exertion (RPE) per session, or motivation to train when using a flexible versus a fixed weekly training order.
Research question 1: Does a flexible weekly training order (FDUP) result in greater strength and total volume performed than a fixed weekly training order (DUP)?
Research question 2: Does FDUP result in greater motivation to train and training satisfaction than DUP due to allowing individuals to choose workouts based upon daily readiness and desire?
The authors hypothesized: 1.) That FDUP would result in greater strength adaptations (absolute and relative) compared to DUP due to greater readiness allowing for more repetitions performed, thus more total volume; and 2.) Subjects would have higher motivation to train and greater satisfaction with a training session with FDUP compared to DUP.
These hypotheses are based on the concept that autoregulating training sessions based upon daily readiness would improve performance.
Subjects were 34 males with at least 6 months of training three times per week and 1RMs of at least the following:
However, only 25 subjects completed the study (FDUP: n=14, DUP, n=11).
This is about a 16% dropout rate, for various reasons, which is not uncommon in a training study. 25 finishing subjects is a pretty good sample size in comparison to similar research (2).
For 9 weeks, each group trained on three non-consecutive days per week. DUP trained in the weekly order of hypertrophy, power, and then strength. FDUP could choose which session they wanted to perform upon entering the laboratory with the stipulation that all session types must be performed each week; therefore, each group would be performing one hypertrophy, one power, and one strength session per week, albeit in a potentially different configuration. At pre- and post-testing, there were 1RM tests for the powerlifts along with body composition assessment via ultrasound.
Further, session RPE was assessed following each training session to gauge a measure of overall post-training fatigue, while motivation to train and training satisfaction were gathered before and after each session, respectively.
The specifics of the training program can be seen in Table 1.
The only difference between groups was the ability of the FDUP group to choose the weekly training order. Squat and bench press were performed every session, while deadlift was only performed during power sessions.
This table displays the training program for the main lifts for the entire study. All notations are “Sets×Reps”. For the power day, percentages of one-repetition maximum (1RM) after week 1 were based upon a predicted 1RM, which was calculated via the Epley Formula using the previous week’s plus set performance on the strength day. Pre-testing was completed 48-72 hours prior to the first training session, and post-testing occurred 48-72 hours following the last session in week 9. Additionally, assistance exercises: (DB lateral raise, DB triceps extension, DB curl for hypertrophy day; pullups and abs for power day; and barbell row and abs for strength day) were performed with either 3×12 or 3×15 in week 1 and decreased to either 2×6 or 2×8 in week 9.
+Plus set= As many repetitions as possible were completed on the last set of this exercise.
*Hypertrophy day progressed based upon plus set repetitions in accordance with Table 2.
** Strength day progressed based upon plus set repetitions in accordance with Table 2.
For progression, a plus set (as many repetitions as possible) was implemented on hypertrophy and strength sessions, and loads were autoregulated for the following week on that session based upon plus set performance (Table 2). Additionally, 2-3 assistance exercises were performed each session in the exact same manner for each group to avoid subjects doing additional training outside of the laboratory.
Adjustments are referring to the same session type for the following week. For example, if 5 more repetitions than required were completed on the strength session in week 2, then 7.5kg would be added for the strength session in week 3. Adapted from Colquhoun et al. (1)
All strength measures increased; however, there were no statistically significant differences between groups for any measure.
Training volume, repetitions completed, and average training intensity
Both groups did roughly the same number of reps on their plus sets, and volume through the rest of the training week was equated. Therefore, there were no significant group differences (p>0.05) in training volume or total reps performed.
Further, since progression was autoregulated, average intensity could be calculated. There was no difference (p>0.05) between groups for average intensity, suggesting that rate of progression was similar between groups. In fact, average intensity throughout the 9 weeks was very similar for squat (DUP: 87% and FDUP: 86% of 1RM), bench press (DUP: 86% and FDUP: 87% of 1RM), and deadlift (DUP: 87% and FDUP: 83% of 1RM).
As previously stated, all strength measures increased from pre- to post-testing, but no differences existed between groups (Table 3). Furthermore, an effect size was calculated for each group from pre- to post-testing to examine the magnitude of change. No effect sizes were drastically different between groups, indicating that the meaningful magnitude of change was also similar.
Research understanding note: The calculated pre-to-post effect size for both groups is not a direct comparison; rather, it is a magnitude inference for each individual group. However, effect sizes can also be calculated in a manner which allows you to compare the groups directly, which may be more helpful than simply calculating pre-to-post effect sizes for each group (3).
Research applicability note: The absolute values for squat, bench press, and deadlift 1RM are presented in Table 3 to show the training status of the individuals. While an average ending deadlift of >180kg in each group (about 400lbs) and squat of 165kg (363lbs) in DUP is not overly impressive to most readers of MASS, this is actually quite good for resistance training research, which makes these findings more applicable than most for a competitive strength sport population.
All perceptual measures (motivation to train, training session satisfaction, and session RPE) were similar between groups. FDUP did not provide an additional psychological benefit compared to the DUP weekly training order of hypertrophy, power, and strength.
There were no changes from pre- to post-testing, nor were there any differences between groups for any of the body composition measures (fat-free mass, fat mass, or body fat percentage). No change here should have been expected, as this was not the point of the study, nor was dietary intake tracked. As a side note, just to give greater insight into the population, body fat percentage was about 11% in FDUP and 13% in DUP for males who weighed 80kg on average.
Powerlifting Total= Sum of squat, bench press, and deadlift. All pre- to post-testing changes are statistically significant; however, no group differences existed for any measure. Adapted from
Colquhoun et al. (1)
This study reported no significant differences in strength gains between groups; therefore, allowing flexibility in weekly session configuration using DUP did not enhance adaptations compared to a fixed session order. Correspondingly, the average number of repetition across all plus-set days was almost identical (FDUP: 9 versus DUP: 8), meaning there were no group differences in training volume.
Previously McNamara and Stearne (2010) reported that a flexible non-linear periodization model produced greater strength gains than an inflexible non-linear approach (4) in a 12-week program that allowed subjects to choose between a 20-, 15-, or 10-repetition day over two weekly training sessions. However, subjects in that study only had the stipulation that they had to complete each training type eight times (1/3 of the 24 total sessions) over the 12 weeks, whereas the presently reviewed study from Colquhoun and colleagues restrained subjects to only allowing within-week flexibility (i.e. hypertrophy, strength, and power all had to be performed within the same week). Because there was less flexibility in Colquhoun’s study, there was an increased chance of an individual training with low readiness, possibly resulting in the conflicting results.
As a side note, these two studies used different terminology: flexible daily undulating periodization versus flexible non-linear periodization. While both are correct, non-linear can refer to weekly or daily undulating; thus, daily undulating is more specific and is an easier term to visualize for the reader (I prefer Colquhoun’s terminology).
This study was also modeled after Zourdos et al. (2016), and the present results also differed slightly in this comparison. Zourdos and colleagues (2) compared two fixed weekly session configurations of DUP in powerlifters: 1.) Hypertrophy, power, and then strength (HPS – the same order as Colquhoun’s fixed group) versus 2.) Hypertrophy, strength, and then power (HSP). HPS was designed to manage fatigue (separating the strength session from the hypertrophy session, which was likely to cause the most muscle damage), and it led to larger strength gains than HSP, as hypothesized (2). Colquhoun then adapted the already-successful HPS configuration and compared it to FDUP. Ultimately, FDUP may have not been more favorable in the presently reviewed study because the comparison model (HPS) already has fatigue and readiness management built into the configuration (i.e. separating strength 96 hours from the most damaging weekly session: hypertrophy). However, none of the above is to say that an FDUP strategy is not useful or never has its place. As with any finding, we cannot look at results in a vacuum; we must learn to think conceptually. Below, I want to present two ways of how understanding conceptually can allow you to utilize a flexible template:
1). When looking further into these results, we see that overall adherence to training may have been slightly better in FDUP. Specifically, both groups started with 16 subjects, for a total of 32 subjects (34 total were screened, but 2 did not meet the inclusion criteria). All 16 finished the FDUP protocol, while only 11 finished the DUP protocol. At the end, data from only 14 subjects were used for FDUP (as 2 were excluded for engaging in exercise outside of the study). Furthermore, 79% of the subjects in the FDUP group completed every training session, while 73% of the subjects in the DUP group completed every training session. It may be that allowing within-week flexibility increased adherence, despite not producing differences in the motivation to train on the Likert scale. Adherence is obviously one of the most important factors when designing a training program. If an individual does not adhere to the training prescription, everything else is of trivial importance. Thus, some flexibility may be beneficial in the long-term.
2). Second, utilizing a “somewhat flexible” weekly configuration may be beneficial. This recommendation takes into account that the already-established weekly order of HPS is beneficial, but fluctuations in daily readiness do happen, and long-term increased adherence should still play a role in program design. Therefore, it seems logical that you could train with a pre-determined order of HPS while reserving the right to still implement a flexible strategy in extreme situations (i.e. < 4 hours sleep or less than 30 minutes of availability to train). To accomplish this, we must think outside of the box.
Even though one hypertrophy, one power, and one strength day were performed within each study by both Colquhoun and Zourdos, if a “somewhat” flexible model (Table 4) is used, the HPS order could be implemented with the freedom to add a power day (since power-type sessions are the least taxing and consume the least amount of time) in the situations mentioned above, then continue on with the next day that had already been scheduled before the power day was "flexed" in. In essence, this would not control for number of session types within each week; it would simply allow a power-type session to be substituted when readiness or time stipulations occur. If preferred, session-type stipulations could be given in the long-term (i.e. over months). Two examples of “somewhat” flexible strategies can be seen in Table 4 compared to the fixed HPS.
In the proposed model, the last two rows present a “somewhat flexible” weekly configuration. In example 1, the lifter sets out with a normal HPS (hypertrophy, power, and strength) weekly training order; however, the individual can “flex” in a power day when necessary without altering the overall pattern. Thus, after the extra power day is inserted in week 1 due to poor readiness (fatigue, sleep disruption, etc.), the individual simply keeps the planned order and picks up with strength in the following session. In example 2, the individual "flexes" in a power day as needed on Monday of week 2 and then simply picks up with hypertrophy-type training in the next session, which would otherwise have been performed on Monday.
It should also be noted that this study provides an example of an integrated periodization strategy (this can be seen in the methods). Specifically, although DUP was used within each week, the methods describe how repetitions on the hypertrophy- and strength-type days decreased every few weeks, thus causing an increase in intensity in an effort to peak. This design shows a within-week DUP strategy encompassed with overall linear changes. I am sure MASS will cover this concept in more detail at some point, but this is an excellent example of how to look beyond the presented data to see the intricate details of a study design. The design demonstrates that these authors possess a solid understanding of scientific and practical program design.
Ultimately, the flexible strategy implemented was not more effective than the fixed HPS order; however, this is not to say that flexible templates have no benefit (as discussed above). It is important to implement a flexible strategy over the long term in future studies to examine if adherence is truly increased. If adherence is indeed increased in the long term, this would be solid evidence for allowing a “somewhat” flexible strategy within your program design to avoid having a high intensity session when readiness to train is poor.