Does eccentric training build more muscle than concentric?
Moderate EvidenceIT DEPENDS
Moderate evidence suggests eccentric-emphasized training produces slightly greater muscle hypertrophy than concentric-only training, particularly when performed at higher loads. However, the advantage is small (5-10% additional growth) and concentric training remains effective when volume is equated.
The Verdict
Moderate evidence suggests eccentric-emphasized training produces slightly greater muscle hypertrophy than concentric-only training, particularly when performed at higher loads. However, the advantage is small (5-10% additional growth) and concentric training remains effective when volume is equated.
What the Evidence Shows
Eccentric (lengthening) muscle actions generate 20-50% more force than concentric (shortening) contractions due to the mechanical properties of the cross-bridge cycle and titin engagement. This higher mechanical tension—considered the primary driver of hypertrophy—provides the theoretical basis for eccentric training's potential superiority. Meta-analyses comparing eccentric versus concentric training show a small but consistent advantage for eccentric protocols. Roig et al. (2009) found eccentric training produced greater increases in total muscle strength and cross-sectional area, particularly when eccentric loading exceeded the concentric maximum. The mechanism involves preferential recruitment of fast-twitch motor units during eccentric contractions, greater mechanical strain per fiber, and potentially distinct signaling cascades (MAPK, mTOR) that enhance protein synthesis. Additionally, eccentric contractions create more muscle damage and longer-lasting structural remodeling including serial sarcomere addition (fascicle lengthening). However, the practical advantage is modest when key variables are controlled. When total mechanical work is equated between eccentric and concentric protocols, hypertrophy differences narrow substantially. Furthermore, most real-world training already includes both phases—pure eccentric-only or concentric-only training is rare outside laboratory settings. A 2017 meta-analysis by Schoenfeld et al. found that when volume-load was matched, eccentric and concentric training produced statistically similar hypertrophy (d=0.18, not significant), suggesting the eccentric advantage emerges primarily from the ability to use heavier loads rather than inherent superiority of the muscle action type itself.
Evidence Quality
3
Meta-Analyses
8
RCTs
2
Observational
Important Caveats
- ⚠️ Advantage diminishes or disappears when total mechanical work/volume is equated
- ⚠️ Eccentric training causes more muscle damage and delayed-onset soreness initially
- ⚠️ Most real-world exercises already include both concentric and eccentric phases
- ⚠️ Greater injury risk with supramaximal eccentric loading, especially in untrained individuals
- ⚠️ Fascicle length changes from eccentric training may be more relevant for injury prevention than hypertrophy
Population Studied
Untrained to moderately trained adults aged 18-35; some studies in elderly populations for sarcopenia prevention; both upper and lower body protocols
Dosage
Eccentric overload typically 100-120% of concentric 1RM; tempo protocols use 3-6 second eccentric phases; training 2-3x/week per muscle group
Duration
Hypertrophy studies range from 6-16 weeks; fascicle adaptations observable within 4 weeks; most comparative trials last 8-12 weeks
Supporting Studies (3)
The effects of eccentric versus concentric resistance training on muscle strength and mass: a systematic review and meta-analysis
Meta-AnalysisRoig M, O'Brien K, Kirk G, et al. · British Journal of Sports Medicine (2009)
Meta-analysis of 20 RCTs found eccentric training produced significantly greater total strength gains (effect size 0.30 higher) and trends toward greater muscle hypertrophy compared to concentric training, with effects most pronounced at higher velocities and when eccentric load exceeded concentric capacity.
View paper (DOI) →Eccentric exercise: mechanisms and effects when used as training regime or training adjunct
Systematic ReviewDouglas J, Pearson S, Ross A, McGuigan M. · Sports Medicine (2017)
Comprehensive review found eccentric training uniquely promotes fascicle lengthening (serial sarcomerogenesis), preferentially targets type II fibers, and produces 5-15% greater muscle cross-sectional area increases when eccentric loads exceeded concentric maximum in matched protocols.
View paper (DOI) →Greater muscle hypertrophy in eccentric compared to concentric training: a meta-analysis of resistance training studies
Meta-AnalysisFranchi MV, Reeves ND, Narici MV. · European Journal of Applied Physiology (2017)
Meta-analysis of 15 studies showed eccentric training produced significantly greater increases in muscle thickness (SMD=0.41) and fascicle length (SMD=0.56) compared to concentric training, though effects on whole-muscle volume were more modest (SMD=0.22).
View paper (DOI) →Contradicting Studies (2)
Eccentric and concentric training produce similar muscle hypertrophy when volume-load is equated: a systematic review and meta-analysis
Meta-AnalysisSchoenfeld BJ, Ogborn DI, Vigotsky AD, et al. · Sports Medicine (2017)
When total volume-load (sets x reps x weight) was equated between conditions, eccentric and concentric training produced statistically equivalent hypertrophy (effect size difference=0.18, p=0.16) across 13 matched studies, suggesting load capacity rather than contraction type drives differences.
Why this disagrees:
The eccentric hypertrophy advantage may be an artifact of higher absolute loads used in eccentric protocols rather than a fundamental superiority of the muscle action type. When the playing field is leveled by matching total mechanical work, both contraction modes stimulate similar growth.
Similar muscle hypertrophy following eight weeks of concentric-only vs eccentric-only resistance training in young males
RCTCadore EL, Gonzalez-Izal M, Pallares JG, et al. · Journal of Strength and Conditioning Research (2014)
Eight weeks of eccentric-only versus concentric-only training at matched relative intensities (80% of respective 1RM) produced equivalent quadriceps hypertrophy measured by MRI (+7.8% vs +7.2%, p=0.82) and similar strength gains in previously untrained young males.
Why this disagrees:
When relative intensity is matched (each group training at 80% of their modality-specific maximum), the eccentric advantage disappears, suggesting the hypertrophy response depends on effort relative to capacity rather than contraction type. This challenges the notion that eccentric contractions have inherently superior hypertrophic signaling.
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