Complex Training vs Plyometrics: What the Evidence Says

Complex training has a case. It does not have a coronation.

Complex training is the gym-floor idea that sounds too elegant to fail: lift something heavy, then do something fast and explosive in the same session, and your nervous system will supposedly become a better engine on command. Coaches often sell it as the smarter, more advanced version of plyometrics alone. Newer evidence does not support that pitch.

A 2026 meta-analysis by Thapa et al. pooled 19 studies with 537 participants, from sedentary adults to highly trained athletes, and asked a practical question: when you compare complex training with ballistic training alone, which one improves performance more? The answer was not "complex training wins." It was "sometimes, for some outcomes, under messy conditions."

Most people do not need a training philosophy. They need a method that matches the job. If your target is maximal strength and some sprint outcomes, complex training may help. If your target is explosive power, reactive strength, and jumping ability more broadly, ballistic training alone is still a serious tool, not the budget version.

The cleanest read of the evidence is simple: complex training can be useful, but plyometrics alone are not a compromise.

What the meta-analysis actually found

In the pooled comparison, complex training beat ballistic training alone for a few specific outcomes. Thapa et al. reported an effect size of 1.12 for one-repetition maximum squat, 0.37 for squat jump height, 0.67 for 10-meter sprint performance, and 0.72 for 40-meter sprint performance. For countermovement jump, jump power, change-of-direction speed, and short sprints under 20 meters, the two approaches produced statistically equivalent results in the analysis.

That pattern is narrower than the usual marketing around complex training. It does not show a universal upgrade in "power." It suggests a possible advantage for heavy-load strength expression and for some longer acceleration tasks, while leaving many explosive outcomes tied.

The same review also reported that training duration mattered. Programs lasting more than 7.5 weeks appeared to produce more favorable results for complex training. That detail makes the finding more plausible. Strength adaptations often need time. They do not arrive because a workout has a clever acronym.

The main problem: the certainty was weak

The authors rated the certainty of evidence as low for the squat jump result and very low for everything else. That is the part many summaries skip. Very low certainty means the apparent advantage could shift substantially with better evidence. It is a warning label, not a footnote.

The published summary available here reports the direction and size of the pooled effects, but it does not provide every confidence interval in the supplied abstract summary. In that situation, the certainty rating matters even more. A medium-size effect estimate with very low certainty is still shaky ground.

Why confidence in the result drops further

A peer-reviewed methodological commentary raised problems that cut directly into the case for complex training. The commentary said at least one ineligible study was included because of a screening error. It also said one study that compared two complex-training formats against each other was misclassified as a complex-training-versus-ballistic-training comparison. If that critique is correct, the pooled advantage for complex training may be inflated.

The same commentary also argued that the inclusion criteria were too broad. Not every "complex training" protocol in the literature actually tests the same idea. Some protocols are built around the post-activation performance enhancement, or PAPE, rationale: use a heavy resistance exercise to prime the nervous system, then follow it with a ballistic movement that benefits from that priming. Other protocols bundle heavy and explosive work together without cleanly testing that mechanism. Pooling both under one label can blur the answer before the statistics start.

This is not a technicality. If the intervention is conceptually mixed, the average effect can look decisive while the real-world prescription remains foggy. That is one reason complex training studies often generate firm opinions and soft conclusions.

The mechanism is real enough, but it is moody

The mechanism most often invoked for complex training is PAPE. In plain terms, a heavy effort can acutely improve performance in a later explosive task. The catch is that this response is highly variable.

A 2025 meta-analysis by Xu et al. reviewed prescription variables for PAPE and found that the response depends on load, rest interval, exercise type, and research methods. Fitness level matters too. The same heavy set that wakes one athlete up can leave another athlete fatigued, slower, and briefly convinced that physics has become personal.

That variability helps explain why chronic complex training results are equivocal. If the proposed edge depends on getting the acute potentiation recipe right, protocol differences across studies will matter a lot. A 2024 systematic review focused on basketball reached a similar practical point: volume, intensity, rest, and exercise sequence vary so much across complex-training studies that comparisons become hard to interpret.

Even acute work supports caution rather than certainty. Byrne et al. studied composite training in hurling players and looked at neuromuscular and fast stretch-shortening cycle drop-jump performance. That kind of experiment supports the idea that acute potentiation can happen. It does not prove that every combined heavy-plus-ballistic program will beat ballistic training alone over weeks or months.

Ballistic training alone already has stronger support than the hype admits

If complex training truly were the superior path to explosive performance, you would expect ballistic training alone to look clearly second-best. It does not.

A much larger 2023 meta-analysis by Ramirez-Campillo et al. pooled 61 studies with 2,576 healthy participants and found that plyometric jump training improved reactive strength across the lifespan, with moderate-certainty evidence. That certainty rating is materially stronger than the very low-certainty superiority claims in the 2026 complex-training comparison. The review also found that programs lasting more than seven weeks and using three sessions per week tended to maximize gains.

That does not make ballistic training universally better. It does mean the evidence for ballistic training as a standalone method is broader, more stable, and less dependent on a narrow sequence of loads and rest periods. If your goal is reactive strength, jump quality, or explosive output, you do not need to treat "heavy lift first" as sacred doctrine.

A 2025 head-to-head study in elite female field hockey players adds some nuance. In that trial, complex training showed a delayed but sustained progression in countermovement jump, while ballistic training alone produced faster early gains that plateaued sooner. The authors also reported that ballistic training alone was insufficient for sustained maximal strength progression in the context of an endurance-heavy team sport. That is useful because it shows a plausible reason for divergence: if an athlete needs both ongoing strength development and explosive work, complex training may solve two problems at once.

Sequence may matter as well. A 2026 randomized trial in judo athletes found sequence-dependent adaptation differences when comparing resistance-before-sprint and sprint-before-resistance training over six weeks. That does not prove the standard complex-training order is always best, but it does support the broader point that design details are not decorative. They are the intervention.

What should an athlete or coach do with this?

Start with the outcome, not the brand name of the method.

• If the main goal is maximal strength plus some sprint improvement, especially over longer acceleration distances, complex training has a reasonable case.
• If the goal is countermovement jump, jump power, change of direction, or reactive strength, the current evidence does not show that complex training reliably beats ballistic training alone.
• If the program needs simplicity, consistency, and fewer moving parts, ballistic training alone has the stronger evidence base for many explosive outcomes.
• If you choose complex training, the details matter: training age, load selection, rest interval, exercise pairing, and program duration all affect whether the proposed advantage appears.

The mistake is treating complexity as proof of superiority. Exercise science does not hand out extra points for choreography.

The honest verdict

The 2026 meta-analysis did not settle the argument in favor of complex training. It found a selective advantage for strength and some sprint outcomes, but many power-related endpoints were equivalent, and the certainty was low to very low. A methodological commentary then raised screening and classification problems that may have made the complex-training result look better than it is. Meanwhile, ballistic training alone already has stronger evidence for reactive strength, and PAPE research shows why the proposed edge of complex training is so sensitive to protocol details.

So the conclusion is not that complex training is useless. It is a tool with a narrow evidence-backed use case, not an elite badge. If you need strength and speed together, use it carefully. If you want explosive performance and you can train plyometrics well and consistently, ballistic training alone is not Plan B. It is often the right plan.