Research
Cellular
Both RT3 and RT6 groups showed significant increases in muscle thickness for elbow extensors (+14% for RT3 and +11% for RT6), rectus femoris (+5% for RT3 and +6% for RT6), and vastus intermedius (+10% for RT3 and +11% for RT6) with no significant between-group differences.
Both training frequencies can be effective for muscle growth in trained individuals.
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Both groups increased elbow extensor thickness (RT3: +14%; RT6: +11%), rectus femoris thickness (RT3: +5%; RT6: +6%), and vastus intermedius thickness (RT3: +10%; RT6: +11%) with no significant between-group differences.
Why this rating
The study design supports robust conclusions about hypertrophy.
Source
Resistance Training Frequencies of 3 and 6 Times Per Week Produce Similar Muscular Adaptations in Resistance-Trained Men
Juraj Šarić et al. · The Journal of Strength and Conditioning Research · 2018
DOI 10.1519/jsc.0000000000002909
rct · n=27Cited 48×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
More from this paper
- Resistance training performed 3 times per week (RT3) and 6 times per week (RT6) produce similar increases in upper-body strength (+4% for RT3 and +6% for RT6) and lower-body strength (+22% for RT3 and +18% for RT6) over a 6-week period.Strong
- No significant pre-to-post intervention increases in muscular endurance were observed in either training group.Strong
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