The Study
Acute and Delayed Effects of a Resistance Training Session Leading to Muscular Failure on Mechanical, Metabolic, and Perceptual Responses.
This study just watched 11 guys do squats and measured how tired they got, but we don’t even know if they were picked fairly or had a fair comparison group. So we can’t say the workout caused anything — we just saw what happened to these 11 people.
Analysis score
Maximum 90 for a randomized controlled trial.
Where the score came from
This study tested what happens when guys do three tough sets of squats until they can't do another rep — and found their legs got super tired and stayed tired for days.
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 538 / 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.
- 1Yes — even though they were trained, their leg power and speed stayed impaired for two full days, meaning their body needed more time to recover than expected.
- 2After the workout: reps dropped by 39% and 55% in later sets; jump height dropped 25–32% right after and stayed 7% lower for two days; leg speed dropped 13–14% for two days; blood ammonia spiked 218%; hand strength didn't change.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Journal of Strength and Conditioning Research
Year
2020
Authors
J. Párraga-Montilla, A. García-Ramos, A. Castaño-Zambudio, F. Capelo-Ramírez, J. González-Hernández, Yaiza Cordero-Rodríguez, P. Jiménez-Reyes
Related Content
Claims (6)
Training muscles to the point of failure reduces gains in strength because it increases fatigue without producing significant improvements in nerve signaling or physical force production.
Among resistance-trained men, performing three sets of back-squats to muscular failure at 60% of one-rep max results in a 38.7% drop in repetitions in the second set and a 54.7% drop in the third set compared to the first set.
After performing low-load back squats to failure, resistance-trained men experience an immediate 25–32% drop in jump height, and this reduction remains at 6.7–7.9% for up to 48 hours.
After one set of low-weight squats performed until exhaustion, resistance-trained men experience a 13–14% drop in how fast they can move the weight at both 24 and 48 hours later.
After performing one set of low-weight squats until exhaustion, handgrip strength in trained men does not change, showing that fatigue from leg exercise does not reduce upper-body strength.
In resistance-trained men, one set of low-load back squats performed to muscle failure causes blood lactate levels to rise by 1.31 to 2.01 effect sizes and ammonia levels to increase by 218% after exercise.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.