Weightlifting Training (WLT) vs. Traditional Resistance Training (TRT) and Plyometrics (PLYO)

WLT is used to improve strength, power, and speed in athletes.
Meta-analysis evaluates WLT effects compared to TRT, PLYO, and control (CON) groups.

Systematic review includes articles with WLT interventions, comparison groups (TRT, PLYO, CON), and measures of strength, power, and/or speed.
Means and standard deviations converted to Hedges’ g effect sizes.

Sixteen studies, 427 participants.
WLT vs. TRT:
- Greater improvements in weightlifting load lifted (p=0.02, $g=1.35$ ).
- Greater improvements in countermovement jump (CMJ) height (p=0.00, $g=0.95$ ).
- Non-significant large effect on linear sprint speed (p=0.13, $g=1.04$ ) and change of direction speed (CODS) (p=0.36, $g=1.21$ ).
WLT vs. PLYO:
- Similar improvements in speed, power, and strength.
- Negligible to moderate, non-significant effects favoring WLT in linear sprint speed (p=0.35, $g=0.20$ ), CODS (p=0.52, $g=0.17$ ), CMJ (p=0.09, $g=0.31$ ), squat jump (p=0.08, $g=0.34$ ), and strength (p=0.20, $g=0.69$ ).

WLT may be advantageous for athletic development, improving strength, power, and speed.
WLT can elicit additional benefits above TRT in weightlifting and jumping performance.

Weightlifting involves maximal weight lifting in snatch and clean and jerk.
Weightlifting exercises improve physical attributes for various sports.
Reduced muscular strength and slow sprint speeds increase musculoskeletal injury risk.
Meta-analyses support WLT for improving vertical jump performance.
Jump performance measures force production under low load and high-velocity demands.
Various strength and power training methods improve strength, power, CODS, and linear sprint speed.
Mixed-method resistance training enhances speed performance compared to TRT alone.
PLYO consists of quick, powerful actions involving muscle lengthening followed by rapid shortening.
WLT and PLYO have a modest advantage over TRT for power and speed measures.
Meta-analysis investigates whether WLT results in greater improvements in strength, power, and speed compared with TRT, PLYO, and CON.
Hypothesis: WLT and PLYO may elicit adaptations in a wider range of physical qualities compared to TRT.

Meta-analysis follows PRISMA guidelines.
Eligibility criteria based on PICO framework: WLT intervention, pre- and post-training measurements, and a comparison group.
WLT intervention includes more than one weightlifting exercise per session and per week.
CON group performs no additional training.
TRT involves the progressive use of resistive loads and different movement velocities.
PLYO involves body weight jumps, hops, bounds, and/or skips.
Exclusion criteria: non-English publications, abstract-only articles, and insufficient information about the WLT intervention.
Four electronic databases searched on April 5, 2021.
Boolean search syntax used: ((olympic OR snatch* OR power clean* OR hang clean* OR clean and jerk OR jerk* OR high pull* OR weightlift*) AND (training or intervention)).
Study titles and abstracts screened to remove duplicates and irrelevant studies.
Full texts reviewed based on inclusion criteria.

Extracted data: sample size, participant characteristics, intervention duration, intervention prescription, reported variables, and means and standard deviation (SD).

Effect sizes (ES) with 95% confidence intervals (CI) calculated.
Hedges’ g calculated from the difference between the standardised mean change.
Random-effects model used for meta-analysis.
Review Manager software used.
Forest plots created and ES classified as negligible, small, moderate, or large.
Statistical significance considered at p<0.05.
Chi-square test used to determine statistical heterogeneity.
I2 statistic used to quantify variation across studies.

95.3% agreement (κ=0.919; p<0.001) between reviewers.
Median total score for included studies was 9 (range 6–12).
Studies scored highly for reporting of point measures, intervention programme prescription, and statistical comparisons.
All studies failed to include activity monitoring in comparison groups.

Median duration of WLT was 8 weeks.
Median training frequency was three times per week.
All studies included variations of full weightlifting movements and accessory strength exercises.

Large, significant effect favoring WLT for improvements in strength (p<0.001, $g=2.40$ ) and SJ performance (p<0.001, $g=1.34$ ).
Moderate, significant effect favoring WLT for improvements in CMJ performance (p=0.006; $g=0.66$ ) and sprint speed (p=0.03, $g=0.66$ ).
Moderate, non-significant effect favoring WLT for improvements in CODS (p =0.16, $g=0.67$ ).

Large, significant effect favoring WLT for improvements in weightlifting performance (p=0.02, $g=1.35$ ).
No effect on improvements in strength or SJ performance.
Large, significant effect favoring WLT for improvements in CMJ (p=0.00, $g=0.95$ ).

WLT is more effective than no supplementary training for improving strength, power, and speed.
WLT may be superior for improvements in weightlifting performance and CMJ height compared to TRT.
Limited differences exist between WLT and PLYO for improvements in strength, jump, sprint speed and CODS performance.
Neural mechanisms are primarily responsible for high force outputs.

Lack of randomised, controlled WLT studies.
Future research should investigate combining WLT, TRT, and PLYO in a periodised plan.

WLT is effective for improving strength, CMJ, SJ, and sprint speed performance.
WLT may elicit additional benefits above TRT alone.
WLT and PLYO may result in similar improvements in strength, jump performance and speed.
Inclusion of weightlifting exercises may be advantageous for goal-specific adaptations and promoting well-rounded athletic development.