Introduction

The westside barbell conjugate method was invented by the late Louie Simmons.  Louie took the concepts from the Soviet Union literature and Bulgarian systems and applied them to his sport of powerlifting.  As Louie and his athletes gained success in powerlifting, the conjugate method started to get applied to sport performance by Louie himself and by other coaches in the strength and conditioning field.  

Generally speaking, the conjugate method is a 4 day a week training program that utilizes an upper and lower split.  These are further broken down into a maximal effort day (1 upper and 1 lower) and a dynamic effort day (1 upper and 1 lower).  The goal of the maximal effort day is to increase an athlete’s absolute strength via heavy loads, whereas the goal of the dynamic effort day is to lift lighter loads at fast speeds to increase an athlete’s rate of force development and power output.  Although you can incorporate flywheel training into your maximal effort day, we will only be touching on dynamic effort in this blog.  

Dynamic effort is performed by moving a submaximal load (50 – 85%) at maximal speeds (1.0 – 0.5 m/s).  Traditional “westside” dynamic effort days are typically performed with submaximal loads with accommodating resistance (i.e., bands or chains) with the goal to move as fast as possible in both the concentric and eccentric phases.  However, one issue with accommodating resistance or traditional resistance training (TRT) as a whole is that athletes are not sufficiently loaded in the eccentric phase.  This is where flywheel training can make a large impact.  

Example of a traditional dynamic effort day by Joe Kenn

Flywheel training overview

Flywheel training provides your athletes with a 1:1 ratio, meaning whatever your athletes put in concentrically, the same output (i.e., velocity) is returned eccentrically.   Generally, flywheel training provides similar concentric outputs, yet much greater outputs in the eccentric phase in comparison to TRT (1).  In addition, Exerfly's Motorized Technology gives you the ability to boost the eccentric repetition up to 80% greater than the concentric repetition, which challenges the athletes with even greater eccentric demands in comparison to TRT and non-motorized flywheel training.  

Example of Motorized flywheel training

Eccentric Training  

Athletes are generally 20-50% stronger in the eccentric phase in comparison to the concentric phase (2).  This means with TRT you are constrained by your concentric strength.  This is where eccentric training (i.e., weight releasers or motorized flywheel training) can come into play as it can create an eccentric overload (eccentric output > concentric output).  Along with other benefits, eccentric training has been shown to increase an athletes rate of force development and power output which likely stems from an increase in fast twitch muscle fibers and muscle-tendon unit stiffness (3).    

Louie knew the benefits of incorporating eccentric training into his program in which he utilized weight releasers (4).  However, one challenge of training with weight releasers is the eccentric phase is often performed at slower movement speeds.  With flywheel training the eccentric phase can be performed at extremely fast speeds and the transition from concentric to eccentric is immediate (see video).  Both of these factors can contribute to and train an athlete’s ability to utilize elastic energy during the stretch shortening cycle (SSC).  Improved SSC function is fundamental to athletic movements such as jumping, running, and throwing.  This was corroborated in a study that examined 14 male sprinters that compared the effects of flywheel training vs traditional eccentric training (weight releasers).  Both groups significantly improved across all performance assessments following the 8 wk intervention, yet the flywheel training group showed greater improvements in countermovement jump and eccentric utilization ratio in comparison to the traditional eccentric training group (1).  These results suggest that flywheel training can enhance SSC utilization to a greater extent than traditional eccentric training, and a potentially more advantageous way to train to improve athletic performance.

Example of how Motorized flywheel training could be incorporated into dynamic effort day

The incorporation of flywheel training into dynamic effort day  

When incorporating dynamic effort day into your training program, the exercise and intensity of the exercise should be dependent on your athlete’s needs.  For instance, if your athlete has weak quads, the dynamic effort exercise should be one that is quad dominant such as a squat.  Similarly, the intensity of the lift (i.e., velocity zone or load) should also be determined based on your athletes’ needs or time of season.  For instance, if your athlete needs to work more on speed or power, a lighter velocity threshold/load can be utilized (Table 1).   Whereas if your athlete needs to work on strength or strength speed, a heavier velocity zone should be incorporated (Table 2).  For more on velocities zones please visit this blog.  

Table 1.  Dynamic effort day with emphasis on eccentric overload

Table 2.  Dynamic effort day with emphasis on intensity

Table 1 and 2 depicts how you may incorporate motorized flywheel training into your dynamic effort day.  For newer coaches or athletes, I generally recommend only manipulating 1 variable at a time (i.e., eccentric overload or velocity threshold/load).  This will allow you to easily gauge what stimulus drove the specific adaptation.  A linear increase of eccentric overload (Table 1) might be most appropriate if the goal of the training block is to increase an athlete’s eccentric capacity.  Whereas a linear increase of velocity threshold/load (Table 2) might be most appropriate if the goal of the training block is to increase athletes’ general strength or during a block that is more concentrically focused.  

Finally, the “generalized load” recommendations are intended for the moderately trained athletic population.  The corresponding load for the velocity threshold recommendations will vary depending on an athlete’s strength and specific exercise.  With flywheel training it is always recommended to utilize the outputs provided by the Exerfly App (i.e., velocity or power) to individualize load.  

Conclusion  

Integrating flywheel training into dynamic effort day can be a great way to surpass your plateau or increase your athletic performance.  Flywheel training can provide greater eccentric loading and improved SSC efficiency which can ultimately lead to greater power output, increases in rate of force development, and improvement in athletic performance.  With proper programming based on your athlete’s needs and time of season, flywheel training offers an effective and adaptable alternative to TRT, traditional eccentric training, and accommodating resistance.  

References

1. Hu, Z, Liu, Y, Huang, K, et al. Effects of inertial flywheel training vs. accentuated eccentric loading training on strength, power, and speed in well-trained male college sprinters. Life 14: 1081, 2024.

2. Nuzzo, JL, Pinto, MD, Nosaka, K, Steele, J. The eccentric:concentric strength ratio of human skeletal muscle in vivo: Meta-analysis of the influences of sex, age, joint action, and velocity. Sports Med 53: 1125–1136, 2023.

3. Suchomel, TJ, Wagle, JP, Douglas, J, et al. Implementing eccentric resistance training—part 1: A brief review of existing methods. J Funct Morphol Kinesiol 4: 38, 2019.

4. Simmons, L. Assisted Eccentrics. Westside Barbell, 2016, www.westside-barbell.com/blogs/the-blog/assisted-eccentrics?srsltid=AfmBOooerAwu_THtXAUkEZm20q0AJMdenPB1_vrCm0y5IErlc2B5l4aF.