Complex training and other exercise sequencing: Pros and cons

There is a lot of terminology around exercise sequencing; complex training, contrast training, ascending training, descending training, French contrast training etc. But there is also a lot of confusion around the pros and cons of each of them. We spoke to Patrick Cormier from the Canadian Sports Institute to break this down over six questions for this week’s Sportsmith Six.

What programming sequences are typically used to elicit the potentiation effects of complex training?

Before we dive into the mechanisms underpinning Complex Training, we should clarify some of the terminology based on recent evidence. Recently, two meta-analyses in Journal of Strength and Conditioning Research ^[1] and Sports Medicine ^[2] both used different terminology to express the exercise sequences presented where the terminology Complex and Contrast training were used to describe similar exercise sequences. As a result, the authors of the two papers teamed up to explore the origins of these training methods and provide clarifications, which has resulted in a new publication in Sports Medicine: Within session exercise sequencing during programming for complex training: Historical perspectives, terminology, and training considerations.

Based on our assessment, we proposed the terminology outlined in Figure 1.

This narrative review made another clarification regarding “post-activation potentiation” (PAP) and “post-activation performance enhancement” PAPE^[1,3]. PAP is thought to be responsible for the acute muscle enhancements (< 1min) in force following excitation of skeletal muscle, e.g., via high load resistance training exercise or conditioning activity (CA) ^[3]. On the other hand, PAPE’s proposed underpinning mechanisms are associated with changes in voluntary force following a CA. These changes persists over longer rest periods of 6-10 minutes. For PAPE, the proposed mechanisms are an increases in temperature, muscle and cellular water content, muscle activation, alterations in motor pattern and potentially other factors. There is not yet agreement around these mechanisms, but it is important for practitioners to consider them when they are programming.

What adaptations are seen in sporting dynamic movements (vertical jump, sprinting, etc) from these types of programming sequencing?

Using the terminology outlined in Figure 1, Contrast and Descending Training appear to have a good transfer to isolated sporting dynamic movements. Recent meta-analyses show slightly greater adaptations in lower body 1RM, vertical jump, sprinting, and change of direction (COD) ability while using Contrast Training. However, both training sequences resulted in similar adaptations in some meta-analyses. This is because there were no statistically significant differences in the studies included due to the large variation in adaptations and program characteristics. Overall, though, including both light and moderately heavy loads within a session is ideal to promote adaptations within both components of the force-velocity relationship, which potentially enhances expression of mechanical power in sporting specific movements.

Contrast Training can enhance improvements in lower body power expression, such as maximal strength, vertical jump, linear sprinting, COD ability, peak power, peak force, and peak velocity. This depends on the athletes’ familiarity with the exercises, strength levels, muscle fibre composition, muscle–tendon properties, and overall performance level. Team sports athletes displayed a slightly greater magnitude (expressed as effect sizes) of adaptations when directly comparing Contrast to Descending Training:

Descending Training resulted in similar but slightly smaller adaptations. However, if maximal strength is the primary goal of the program, then Descending Training could be optimal since the heavy load exercises come at the beginning of the session. That way, fatigue doesn’t affect the movement quality of the exercises towards the end of the session. With Contrast Training, this method may be preferable after acquiring the prerequisite levels of strength required to maximise its benefits.

Complex training alternates “biomechanically similar” high load strength and lower load power exercises. Do you have a checklist or list of rules when developing these two sets of exercises to ensure they are sufficiently similar to have an effect?

Traditionally, “biomechanically similar” exercises involving high loads (>85% 1RM) and light load power exercises are implemented in “contrast pairs.” However, the interpretation of this method has evolved, and its implementation is quite flexible.

The cardinal rule when implementing Contrast Training is to select your exercises based on the context of your athlete and the adaptation you want to achieve, rather than following strict rules. That said, when the objective is to optimise potentiation within contrast pairings:

1. Use light to moderate load conditioning activities. <85% 1RM tends to elicit the greatest acute potentiation and chronic adaptations to Contrast Training.

2. Select exercises based on similar movement pattern characteristics to produce greater potentiation.

3. Pairing exercises that have similar contraction modes (e.g., concentric with concentric, rather than isometric with concentric) may limit motor pattern interference, which could contribute to the lag or attenuation of PAPE.

4. Strong and experienced athletes can tolerate shorter intra-contrast rest periods of <5 minutes. However, weak athletes require longer periods to overcome the effects of fatigue.

The research shows that the responses to these methods are highly individual. So I challenge practitioners to consider the recommendations based on available research, but also experiment with their athletes to find optimal, individualized rest periods and exercise intensities.

You may have noticed I did not give many “rules” for implementing Complex Training. There are many factors that can affect adaptation, making it highly individual.

Rather than focusing on “rules” you should aim for the goals and objectives of the training to match the needs of the athlete and their sport, while also considering the adaptive principles to achieve those goals. When programming Complex Training, I ask myself these three questions:

1. Are these exercises and intensities appropriate for the individual?
2. How will each exercise effect the subsequent movements throughout the session, i.e., exercise sequence?
3. Considering the principles of adaptation, will this session – this bout of stress – help the athlete adapt in the long term?

Does the athlete’s level or training history have any impact on the effectiveness of each training sequence?

This is a very important aspect when implementing complex training methods. It is unclear whether athlete calibre is a true mediator of acute or long term adaptations. However, athletes’ strength levels are and do have such an influence.

Depending on the context, elite athletes may inherently possess greater levels of strength, perhaps based on their training history and their fibre type composition. In this context, higher calibre athletes have developed superior adaptations, especially from Contrast Training. Typically, athletes that can squat ≥1.75-2x their body mass will see greater levels of PAPE in lower body movements, need shorter rest periods between sets and will benefit most from Contrast Training. Further, being able to bench press ≥1.35x body mass appears to be a prerequisite for upper body PAPE.

Does the intensity or volume of one of the components positively or negatively affect the overall outcome?

Generally, based on findings from recent meta-analyses, using conditioning activities such as light plyometrics or moderate load (30-84% 1RM) exercises were beneficial for eliciting PAPE compared to heavy loads in contrast pairings. A minimum of three weeks with 2-4 sessions per week and at least 1-3 contrast pair sets is necessary for PAPE.

Now that we have a general idea of the adaptations from Complex Training with some  guidelines for programming, it is important to dive deeper into this area of training and future research. For example, Poulos et al. ^[7] recently published work on Contrast Training with rugby 7’s athletes. They assessed the force-time and velocity-time characteristics of reactive strength index, active stiffness, peak power, impulse and jump height in conjunction with contrast pairings, such as a jump squat with drop jumps. This kind of research allows us to examine the nuances of PAPE in Contrast Training, and future researchers should explore this area more deeply.

Hopefully, the clarifications from our recent paper can guide future research on the topic. There is an abundance of literature on Complex Training for practitioners to draw upon. However, now that we know the state of the literature on this topic, we must address the methodological gaps in the research so we can provide better solutions and smooth out the programming puzzle around Complex Training.

What are the biggest mistakes you see young practitioners/clinicians make and what advice would you give them to help?

This is an interesting question, since I consider myself a young practitioner. Regardless, the biggest mistake I see in young(er) practitioners is getting stuck in absolutes, which biases their view of training and how they interact with others, and stunts their growth as a practitioner and a person. In every situation we must make our best judgment based on the context in front of us.

There is a lot of information out there, which can make it difficult to find evidence-informed solutions for our practice. However, keeping an open mind is paramount. As long as you have a rationale that you have logically thought out based on the context, you will do great.

Another piece of advice would be to meet and collaborate with as many people from as many different countries as you can. This will open your mind and will make you a better practitioner in the long run. Chats with physiotherapists, technical staff, athletic therapists, team physicians, even the kit man could give you valuable advice that could impact your practice and bring joy to your work.