The Study
Blood flow restriction does not augment low force contractions taken to or near task failure
We don't know how this study was done — maybe people were randomly assigned, maybe not. So we can't say for sure if BFR helps or doesn't help muscles grow. All we have is a short summary, not the full story.
Analysis score
Maximum 90 for a randomized controlled trial.
Where the score came from
This study tested if lifting very light weights, with or without squeezing your leg to cut off blood flow, can build muscle like lifting heavy weights.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 544 / 100
Quality score
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Light weights can make some muscle growth and improve endurance, but not as much as heavy weights for strength or upper thigh size.
- 2Lifting heavy weights (70% of max) made people 2.09 kg stronger and muscles at the upper thigh 0.16–0.15 cm thicker.
- 3Lifting light weights (15% of max) with or without blood flow made muscles at the lower thigh 0.09 cm thicker and improved endurance by 7.9 reps.
- 4No other strength gains.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
European Journal of Sport Science
Year
2020
Authors
Samuel L. Buckner, Matthew B. Jessee, Scott J. Dankel, Kevin T. Mattocks, J. Grant Mouser, Zachary W. Bell, Takashi Abe, John P. Bentley, Jeremy P. Loenneke
Related Content
Claims (4)
After eight weeks of low-intensity resistance training, whether or not blood flow restriction is used, people can perform an average of 7.9 more repetitions in endurance tests.
After eight weeks of lifting heavy weights at 70% of maximum capacity, people gain about 2.09 kg in their one-repetition maximum strength. Lifting very light weights at 15% of maximum, with or without restricting blood flow, does not result in a significant increase in one-repetition maximum strength.
After eight weeks of resistance training, the thickness of muscle at the 70% thigh site increases by an average of 0.09 centimeters, whether the training uses heavy or light weights and whether or not blood flow is restricted.
After eight weeks of training with very light weights, muscle thickness increases less at the middle and upper thigh compared to training with heavy weights, regardless of whether blood flow is restricted.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.