People who do CrossFit-style workouts can jump higher than regular active people, but they don’t jump noticeably higher than people who lift weights regularly.
Scientific Claim
Functional fitness training practitioners demonstrate higher jump height than physically active controls, but show no statistically significant difference in jump height compared to strength training practitioners, suggesting that both training styles may support similar levels of lower limb explosive power.
Original Statement
“Jump height was higher (p = 0.003) for the FFT group (53.5 ± 2.4 cm) compared to the control group (45.7 ± 3.6 cm), and did not differ in relation to the ST group (50.8 ± 5.7 cm; p = 0.058).”
Evidence Quality Assessment
Claim Status
overstated
Study Design Support
Design supports claim
Appropriate Language Strength
association
Can only show association/correlation
Assessment Explanation
The authors imply equivalence between FFT and ST, but p=0.058 is not statistically significant and does not prove equivalence. The claim must reflect association, not conclusion.
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.
Systematic Review & Meta-AnalysisLevel 1aWhether FFT and ST produce equivalent improvements in vertical jump height across diverse populations.
Whether FFT and ST produce equivalent improvements in vertical jump height across diverse populations.
What This Would Prove
Whether FFT and ST produce equivalent improvements in vertical jump height across diverse populations.
Ideal Study Design
A meta-analysis of 15+ RCTs comparing FFT (e.g., CrossFit, WOD-based) vs. ST (e.g., 3–5 sets of 6–10 reps at 70–85% 1RM) in healthy adults, measuring vertical jump height as primary outcome after 8–16 weeks of training.
Limitation: Cannot resolve heterogeneity in training protocols or participant experience levels.
Randomized Controlled TrialLevel 1bWhether FFT and ST cause equivalent gains in vertical jump height over time.
Whether FFT and ST cause equivalent gains in vertical jump height over time.
What This Would Prove
Whether FFT and ST cause equivalent gains in vertical jump height over time.
Ideal Study Design
A 16-week double-blind RCT of 80 untrained men aged 20–30 randomized to FFT (3x/week, mixed modal) or ST (3x/week, barbell lifts) with pre/post vertical jump testing using force plates, controlling for baseline power and nutrition.
Limitation: Short duration may not reflect long-term adaptations.
Prospective Cohort StudyLevel 2bWhether long-term FFT or ST practitioners maintain higher jump height than controls over years.
Whether long-term FFT or ST practitioners maintain higher jump height than controls over years.
What This Would Prove
Whether long-term FFT or ST practitioners maintain higher jump height than controls over years.
Ideal Study Design
A 3-year cohort study tracking 150 experienced (≥2 years) FFT and ST practitioners with annual vertical jump testing, compared to age-matched controls, adjusting for training volume and recovery.
Limitation: Cannot isolate training effect from genetic or lifestyle confounders.
Evidence from Studies
Supporting (1)
The study found that people who do functional fitness jumps as high as those who do weightlifting, and both jump higher than regular active people — so both types of training help you jump just as well.