Study analysis · The Journal of nutrition · 2018
Forget what you've heard: healthy older adults can build muscle just as well as anyone—and this study proves it.
After 12 weeks of strength training, older adults got stronger and gained muscle, and their bodies still responded to protein just fine.
Overview
What the study found
The study in plain English — the bottom line, every takeaway we extracted, and what to do with them.
In simple terms
This study is like watching a group of older people exercise for 12 weeks and seeing what happens to their muscles. It tells us that after training, their muscles got bigger and stronger, and that eating amino acids still made their muscles build protein. But because there was no comparison group of people who didn't train, we can't be sure the training caused these changes. It's like seeing that kids who eat breakfast do better in school, but we can't say breakfast causes better grades without comparing to kids who don't eat breakfast.
What’s the bottom line?
Researchers wanted to know if older adults have trouble building muscle from protein, and if exercise training helps. They trained 19 older adults for 12 weeks and measured muscle growth and protein building.
How strong is this study?
This study is like a science project where you only test one group of people and don't have a 'control' group to compare. That makes it harder to trust the results because other things could have caused the changes. Also, only 19 people were in the study, which is a small number, so we can't be sure the results apply to everyone. It's like if you only asked 19 kids if they like pizza, you can't say all kids like pizza.
0 / 100
- COI disclosureconflicts of interest not disclosed
- Data availabilitydata not shared
- Code availabilitycode not shared
15 / 100
- Randomizationrandomization unclear
- Blindingblinding unclear
- Control groupno control group
- Sample size (n=19)+1.8/20
- Follow-up+10/10
100 / 100
23 / 100
- P-valuesno p-values reported
- Effect sizeno effect size reported
- Confidence intervalsno confidence intervals
- Pre-registration+15/15
Each component is scored out of 100 and then capped by the study design — a case series cannot reach the ceiling a randomised trial can, however well it is reported.
Where it sits
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 531 / 100
Probability of being correct
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
This design cannot establish causation — the findings describe an association, not a cause. This is an observational cohort study without a control group, randomization, or blinding. It cannot establish cause-and-effect relationships. The observed changes could be due to other factors such as natural aging, placebo effects, or measurement variability.
No Conflicts
No conflicts of interest identified
No conflicts of interest declared in the provided abstract; the study appears independently conducted.
The text is an abstract without a conflict of interest section or funding statement. The absence of such information limits the assessment of potential biases.
Key takeaways
- 01
After 12 weeks of training, muscle strength went up by 16%, lean mass by 2%, and muscle size by 27%.
- 02
The rate of muscle protein building at rest went up by 36% after training.
- 03
But the immediate response to eating essential amino acids did not change after training.
- 04
This means that older adults can build muscle with training, and they don't seem to have a problem responding to protein.
Surprising findings
- Resistance training did not improve the acute muscle protein synthesis response to essential amino acid ingestion.It was expected that training would enhance the muscle's sensitivity to amino acids, but the study found no change. This contradicts the hypothesis that training would 'prime' the muscle to respond better to protein.
- Despite the lack of improvement in acute response, basal muscle protein synthesis increased by 36% after training.This suggests that the benefits of training on muscle protein synthesis are more about the resting state than the immediate response to feeding, which is a nuanced finding.
Practical takeaways
Engage in regular resistance training (e.g., lifting weights 2-3 times per week) to improve strength and muscle mass, even in your 70s.
This study had a small sample size (n=19) and only included healthy older adults. Results may not apply to those with chronic conditions or frailty.
low confidenceConsume adequate protein, but don't stress about 'anabolic resistance' if you're healthy and active.
The study used a small dose of essential amino acids (6.8 g) and did not test different protein amounts or timing.
low confidenceWhy this study matters
Strength gains in your 70s? Yes, it's possible.
In this study, 19 healthy older adults (average age 71) did progressive resistance training for 12 weeks. Their muscle strength increased by 16%, lean mass by 2%, and muscle cross-sectional area by 27%. These are significant improvements, showing that even at 70+, the body can adapt to training.
Many people believe that muscle loss is inevitable with age, but this shows that with proper training, older adults can still build muscle and strength, which is crucial for maintaining independence and quality of life.
Basal muscle protein synthesis jumps 36% after training
After 12 weeks of training, the rate at which muscles build protein at rest increased by 36%. This means that even when not exercising, the body is more efficient at maintaining and repairing muscle tissue.
This suggests that regular training has a lasting effect on muscle maintenance, not just during the workout. It's a powerful motivator for consistency.
Protein response: No anabolic resistance in healthy older adults
The study found that a small dose of essential amino acids (6.8 g) stimulated muscle protein synthesis and mTORC1 signaling both before and after training. Training did not improve this acute response, but the fact that it worked at all suggests that anabolic resistance is not a problem in this healthy population.
This challenges the common belief that older adults need extra protein or special timing to build muscle. It suggests that as long as you're healthy, your muscles can still respond to protein.
Want the whole report?
Detailed mode opens the full scientific breakdown — every score component, the methodology, conflicts of interest, the evidence analysis behind each claim, and the raw study data.
Overview
What the study found
The study in plain English — the bottom line, every takeaway we extracted, and what to do with them.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Researchers wanted to know if older adults have trouble building muscle from protein, and if exercise training helps. They trained 19 older adults for 12 weeks and measured muscle growth and protein building.
Research results
After 12 weeks of training, muscle strength went up by 16%, lean mass by 2%, and muscle size by 27%. The rate of muscle protein building at rest went up by 36% after training. But the immediate response to eating essential amino acids did not change after training.
What this means - more context
This means that older adults can build muscle with training, and they don't seem to have a problem responding to protein.
To determine if muscle protein anabolism is resistant to essential amino acids and whether resistance exercise training improves muscle sensitivity to EAA in healthy older adults.
In a 12-week resistance training study of 19 healthy older adults (mean age 71±4 y), resistance training increased strength by 16%, lean mass by 2%, and muscle cross-sectional area by 27%. Basal muscle protein synthesis increased by 36% after training, but the acute response to 6.8 g essential amino acids was not altered. The authors conclude that anabolic resistance to amino acids may not be a problem in healthy older adults. Note: This study has published corrections/errata.
Methods Used
Longitudinal study of 19 healthy older adults (mean age 71±4 y, BMI 28±3) who underwent 12 weeks of progressive resistance exercise training (60-75% 1-repetition maximum). Body composition, strength, and metabolic health were measured pre- and posttraining. Stable isotope infusion experiments with muscle biopsies were used to measure muscle protein synthesis and markers of amino acid sensing in basal state and in response to 6.8 g of essential amino acid ingestion.
Main Finding
Resistance training increased muscle strength by 16%, lean mass by 2%, and muscle cross-sectional area by 27% (P<0.05). Basal muscle protein synthesis increased by 36% after training (P<0.05). The response of muscle protein synthesis and mTORC1 signaling to essential amino acid ingestion was not affected by training. The authors conclude that anabolic resistance to amino acids may not be a problem in healthy older adults.
Confidence Level
Limited - based on abstract only, full methodology not available
Study Flags
Red Flags
- •Full text not available - methodology details cannot be verified
- •Study has published corrections/errata
- •Small sample size (n=19)
Surprising Findings
Resistance training did not improve the acute muscle protein synthesis response to essential amino acid ingestion.
It was expected that training would enhance the muscle's sensitivity to amino acids, but the study found no change. This contradicts the hypothesis that training would 'prime' the muscle to respond better to protein.
Practical Takeaways
Engage in regular resistance training (e.g., lifting weights 2-3 times per week) to improve strength and muscle mass, even in your 70s.
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 531 / 100
Probability of being correct
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
Human Cohort Study
Subject
Lower probability
on the GRADE evidence scale
This study is like watching a group of older people exercise for 12 weeks and seeing what happens to their muscles. It tells us that after training, their muscles got bigger and stronger, and that eating amino acids still made their muscles build protein. But because there was no comparison group of people who didn't train, we can't be sure the training caused these changes. It's like seeing that kids who eat breakfast do better in school, but we can't say breakfast causes better grades without comparing to kids who don't eat breakfast.
No conflicts of interest were detected in this study. No score impact.
Strengths
- Longitudinal design with pre- and post-training measurements
- Use of stable isotope infusion and muscle biopsies to measure MPS
- Measured multiple outcomes (strength, lean mass, CSA, MPS, signaling)
Weaknesses
- No control group
- No randomization
- No blinding
Methodology
Evidence Keywords
Statistical Reporting
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Researchers wanted to know if older adults have trouble building muscle from protein, and if exercise training helps. They trained 19 older adults for 12 weeks and measured muscle growth and protein building.
Research results
After 12 weeks of training, muscle strength went up by 16%, lean mass by 2%, and muscle size by 27%. The rate of muscle protein building at rest went up by 36% after training. But the immediate response to eating essential amino acids did not change after training.
What this means - more context
This means that older adults can build muscle with training, and they don't seem to have a problem responding to protein.
To determine if muscle protein anabolism is resistant to essential amino acids and whether resistance exercise training improves muscle sensitivity to EAA in healthy older adults.
In a 12-week resistance training study of 19 healthy older adults (mean age 71±4 y), resistance training increased strength by 16%, lean mass by 2%, and muscle cross-sectional area by 27%. Basal muscle protein synthesis increased by 36% after training, but the acute response to 6.8 g essential amino acids was not altered. The authors conclude that anabolic resistance to amino acids may not be a problem in healthy older adults. Note: This study has published corrections/errata.
Methods Used
Longitudinal study of 19 healthy older adults (mean age 71±4 y, BMI 28±3) who underwent 12 weeks of progressive resistance exercise training (60-75% 1-repetition maximum). Body composition, strength, and metabolic health were measured pre- and posttraining. Stable isotope infusion experiments with muscle biopsies were used to measure muscle protein synthesis and markers of amino acid sensing in basal state and in response to 6.8 g of essential amino acid ingestion.
Main Finding
Resistance training increased muscle strength by 16%, lean mass by 2%, and muscle cross-sectional area by 27% (P<0.05). Basal muscle protein synthesis increased by 36% after training (P<0.05). The response of muscle protein synthesis and mTORC1 signaling to essential amino acid ingestion was not affected by training. The authors conclude that anabolic resistance to amino acids may not be a problem in healthy older adults.
Confidence Level
Limited - based on abstract only, full methodology not available
Study Flags
Red Flags
- •Full text not available - methodology details cannot be verified
- •Study has published corrections/errata
- •Small sample size (n=19)
Surprising Findings
Resistance training did not improve the acute muscle protein synthesis response to essential amino acid ingestion.
It was expected that training would enhance the muscle's sensitivity to amino acids, but the study found no change. This contradicts the hypothesis that training would 'prime' the muscle to respond better to protein.
Practical Takeaways
Engage in regular resistance training (e.g., lifting weights 2-3 times per week) to improve strength and muscle mass, even in your 70s.
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 531 / 100
Probability of being correct
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
Human Cohort Study
Subject
Lower probability
on the GRADE evidence scale
This study is like watching a group of older people exercise for 12 weeks and seeing what happens to their muscles. It tells us that after training, their muscles got bigger and stronger, and that eating amino acids still made their muscles build protein. But because there was no comparison group of people who didn't train, we can't be sure the training caused these changes. It's like seeing that kids who eat breakfast do better in school, but we can't say breakfast causes better grades without comparing to kids who don't eat breakfast.
No conflicts of interest were detected in this study. No score impact.
Strengths
- Longitudinal design with pre- and post-training measurements
- Use of stable isotope infusion and muscle biopsies to measure MPS
- Measured multiple outcomes (strength, lean mass, CSA, MPS, signaling)
Weaknesses
- No control group
- No randomization
- No blinding
Methodology
Evidence Keywords
Statistical Reporting
Scoring
How strong is this study?
This study is like a science project where you only test one group of people and don't have a 'control' group to compare. That makes it harder to trust the results because other things could have caused the changes. Also, only 19 people were in the study, which is a small number, so we can't be sure the results apply to everyone. It's like if you only asked 19 kids if they like pizza, you can't say all kids like pizza.
0 / 100
- COI disclosureconflicts of interest not disclosed
- Data availabilitydata not shared
- Code availabilitycode not shared
15 / 100
- Randomizationrandomization unclear
- Blindingblinding unclear
- Control groupno control group
- Sample size (n=19)+1.8/20
- Follow-up+10/10
100 / 100
23 / 100
- P-valuesno p-values reported
- Effect sizeno effect size reported
- Confidence intervalsno confidence intervals
- Pre-registration+15/15
Each component is scored out of 100 and then capped by the study design — a case series cannot reach the ceiling a randomised trial can, however well it is reported.
Where it sits
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 531 / 100
Probability of being correct
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
This design cannot establish causation — the findings describe an association, not a cause. This is an observational cohort study without a control group, randomization, or blinding. It cannot establish cause-and-effect relationships. The observed changes could be due to other factors such as natural aging, placebo effects, or measurement variability.
No Conflicts
No conflicts of interest identified
No conflicts of interest declared in the provided abstract; the study appears independently conducted.
The text is an abstract without a conflict of interest section or funding statement. The absence of such information limits the assessment of potential biases.
Standing
Who’s using this study?
The videos and claims on this site that lean on this study, and the researchers who wrote it.
1 video from Siim Land cite this study, drawing 1 claim from it.
- Good evidence
Good evidence supports this claim, with little to contradict it.
Evidence