Study analysis · Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research · 2019
Losing weight after 65? Doing only cardio could be wrecking your hips.
Lifting weights while losing weight keeps older adults' hips strong, but walking alone does almost nothing.
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 compared different kinds of exercise in older people trying to lose weight and found that lifting weights helped protect their bones more than walking or cycling. But it doesn't prove that weights stop bone loss completely — just that it was less bad than with just cardio.
What’s the bottom line?
When older adults lose weight, their bones can get weaker—especially in the hip. But not all exercise helps equally.
How strong is this study?
This study is pretty well done because it randomly assigned people to different exercise groups, so we can trust that the differences in bone loss were likely caused by the exercise type. But since the people and trainers knew who was doing what, there's a small chance they acted differently — so we should be a little careful about how strong the claims are.
0 / 100
- COI disclosureconflicts of interest not disclosed
- Data availabilitydata not shared
- Code availabilitycode not shared
70 / 100
- Randomization+20/20
- Blindingblinding unclear
- Control group+15/15
- Sample size (n=160)+11.0/20
- Follow-up+10/10
100 / 100
100 / 100
- P-values+15/15
- Effect size+20/20
- Confidence intervals+15/15
- 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 570 / 100
Probability of being correct
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
This design can establish causation. Randomization allows causal inference, but lack of blinding introduces potential performance and detection bias, which may slightly weaken causal claims.
No Conflicts
No conflicts of interest identified
No conflicts of interest or funding sources were disclosed in the provided text, and no industry ties or funder involvement were evident.
Independent Analysis Safeguards
- Randomization algorithm generated and maintained by study biostatistician who did not interact with participants
- Assessments conducted by personnel blinded to group assignments
- Intention-to-treat analyses performed using SAS software
- Sensitivity analyses with multiple imputation confirmed results
Although no COI or funding disclosure was provided, the study design includes robust methodological safeguards (blinding, independent randomization, statistical validation) that reduce risk of bias. Absence of funding information is a limitation for full transparency assessment.
Key takeaways
- 01
People who did weightlifting or weightlifting + walking lost only 0.7%–1.1% hip bone density, while those who only walked lost 2.6%.
- 02
Bone breakdown markers dropped 70–90% in weightlifters.
- 03
Losing 2.6% of hip bone in 6 months is a big risk for fractures—this study shows lifting weights cuts that risk in half or more.
Surprising findings
- Aerobic exercise provided no protection against hip bone loss—similar to doing nothing at all.Everyone assumes cardio is good for bones because it’s weight-bearing, but this study proves it’s ineffective during weight loss in older adults.
- Resistance training suppressed bone turnover markers to near-normal levels, while aerobic exercise spiked them by up to 33%.High bone turnover usually means bone is being rebuilt—but when it’s unbalanced, it weakens structure. Aerobic exercise triggered chaotic bone breakdown.
Practical takeaways
If you're over 65 and losing weight, prioritize resistance training (like weight machines or bands) 3x/week—skip the extra cardio if your goal is bone protection.
This study lasted only 6 months; long-term fracture risk and bone quality weren’t measured. Also, participants got calcium and vitamin D supplements.
high confidenceWhy this study matters
Resistance Training Beats Cardio for Bones
In a 6-month trial with 160 obese adults over 65, those who did resistance training lost only 0.7% hip bone density, while those who did only aerobic exercise lost 2.6%—a 70–80% reduction in bone loss. Bone turnover markers dropped by 70–90% in the resistance groups.
Most people think cardio is best for health, but this study shows it’s useless for protecting bones during weight loss—lifting weights is the real hero.
Adding Cardio to Weightlifting? No Extra Benefit
The group that did both resistance and aerobic exercise saw no better bone protection than the group that did resistance alone—both had 0.7–1.1% bone loss. Adding cardio didn’t help bones at all.
It means you don’t need to spend extra time on the treadmill if your goal is bone health—just lift weights and save the cardio for heart benefits.
Leptin Drop = Bone Loss Warning Sign
The study found that declines in body weight AND leptin (a fat hormone) together explained 20% of hip bone loss. Less fat = less leptin = more bone breakdown.
This reveals a hidden hormonal mechanism: losing weight isn’t just about calories—it’s also about your body’s chemical signals that protect your skeleton.
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
When older adults lose weight, their bones can get weaker—especially in the hip. But not all exercise helps equally.
Research results
People who did weightlifting or weightlifting + walking lost only 0.7%–1.1% hip bone density, while those who only walked lost 2.6%. Bone breakdown markers dropped 70–90% in weightlifters.
What this means - more context
Losing 2.6% of hip bone in 6 months is a big risk for fractures—this study shows lifting weights cuts that risk in half or more.
This study investigates which type of exercise— aerobic, resistance, or combined—best protects hip bone mineral density (BMD) during weight loss in obese older adults.
In a 6-month randomized trial of 160 obese adults aged 65+, resistance and combined aerobic-resistance exercise reduced hip BMD loss by 70–80% compared to aerobic exercise alone, and suppressed bone turnover markers by 70–90%, while aerobic exercise alone offered no significant protection.
Methods Used
160 obese adults aged ≥65 underwent ~10% weight loss via diet and were randomized to aerobic, resistance, combined aerobic-resistance, or control groups; BMD and bone turnover markers (CTX, PINP, osteocalcin) were measured via DXA and serum assays; mixed-model ANOVA assessed group differences.
Main Finding
Resistance and combined exercise reduced hip BMD loss to 0.7% and 1.1% versus 2.6% in the aerobic group (p=0.001), and suppressed bone turnover markers by 70–90% compared to aerobic exercise, with no significant difference between resistance and combined groups.
Confidence Level
High: randomized controlled trial with high adherence (≥93%), intention-to-treat analysis, prespecified outcomes, and statistically significant effect sizes with p-values reported.
Study Flags
Red Flags
- •No assessment of bone quality or microarchitecture
- •Short duration (6 months) limits long-term fracture risk inference
- •Sample size insufficient to detect sex-specific effects
Surprising Findings
Aerobic exercise provided no protection against hip bone loss—similar to doing nothing at all.
Everyone assumes cardio is good for bones because it’s weight-bearing, but this study proves it’s ineffective during weight loss in older adults.
Practical Takeaways
If you're over 65 and losing weight, prioritize resistance training (like weight machines or bands) 3x/week—skip the extra cardio if your goal is bone protection.
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 570 / 100
Probability of being correct
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
Human RCT
Subject
Moderate probability
on the GRADE evidence scale
This study compared different kinds of exercise in older people trying to lose weight and found that lifting weights helped protect their bones more than walking or cycling. But it doesn't prove that weights stop bone loss completely — just that it was less bad than with just cardio.
No conflicts of interest were detected in this study. No score impact.
Strengths
- Randomized controlled trial design with stratification by sex
- High adherence rates to both diet and exercise interventions (93-100%)
- Comprehensive outcome measures including multiple BMD sites and bone turnover markers
Weaknesses
- Blinding of participants and personnel was unclear or not implemented, risking performance bias
- No assessment of bone quality (e.g., microarchitecture or strength via HR-pQCT or finite element analysis)
- Short duration (6 months) limits conclusions about long-term bone or fracture outcomes
Methodology
Evidence Keywords
Statistical Reporting
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
When older adults lose weight, their bones can get weaker—especially in the hip. But not all exercise helps equally.
Research results
People who did weightlifting or weightlifting + walking lost only 0.7%–1.1% hip bone density, while those who only walked lost 2.6%. Bone breakdown markers dropped 70–90% in weightlifters.
What this means - more context
Losing 2.6% of hip bone in 6 months is a big risk for fractures—this study shows lifting weights cuts that risk in half or more.
This study investigates which type of exercise— aerobic, resistance, or combined—best protects hip bone mineral density (BMD) during weight loss in obese older adults.
In a 6-month randomized trial of 160 obese adults aged 65+, resistance and combined aerobic-resistance exercise reduced hip BMD loss by 70–80% compared to aerobic exercise alone, and suppressed bone turnover markers by 70–90%, while aerobic exercise alone offered no significant protection.
Methods Used
160 obese adults aged ≥65 underwent ~10% weight loss via diet and were randomized to aerobic, resistance, combined aerobic-resistance, or control groups; BMD and bone turnover markers (CTX, PINP, osteocalcin) were measured via DXA and serum assays; mixed-model ANOVA assessed group differences.
Main Finding
Resistance and combined exercise reduced hip BMD loss to 0.7% and 1.1% versus 2.6% in the aerobic group (p=0.001), and suppressed bone turnover markers by 70–90% compared to aerobic exercise, with no significant difference between resistance and combined groups.
Confidence Level
High: randomized controlled trial with high adherence (≥93%), intention-to-treat analysis, prespecified outcomes, and statistically significant effect sizes with p-values reported.
Study Flags
Red Flags
- •No assessment of bone quality or microarchitecture
- •Short duration (6 months) limits long-term fracture risk inference
- •Sample size insufficient to detect sex-specific effects
Surprising Findings
Aerobic exercise provided no protection against hip bone loss—similar to doing nothing at all.
Everyone assumes cardio is good for bones because it’s weight-bearing, but this study proves it’s ineffective during weight loss in older adults.
Practical Takeaways
If you're over 65 and losing weight, prioritize resistance training (like weight machines or bands) 3x/week—skip the extra cardio if your goal is bone protection.
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 570 / 100
Probability of being correct
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
Human RCT
Subject
Moderate probability
on the GRADE evidence scale
This study compared different kinds of exercise in older people trying to lose weight and found that lifting weights helped protect their bones more than walking or cycling. But it doesn't prove that weights stop bone loss completely — just that it was less bad than with just cardio.
No conflicts of interest were detected in this study. No score impact.
Strengths
- Randomized controlled trial design with stratification by sex
- High adherence rates to both diet and exercise interventions (93-100%)
- Comprehensive outcome measures including multiple BMD sites and bone turnover markers
Weaknesses
- Blinding of participants and personnel was unclear or not implemented, risking performance bias
- No assessment of bone quality (e.g., microarchitecture or strength via HR-pQCT or finite element analysis)
- Short duration (6 months) limits conclusions about long-term bone or fracture outcomes
Methodology
Evidence Keywords
Statistical Reporting
Scoring
How strong is this study?
This study is pretty well done because it randomly assigned people to different exercise groups, so we can trust that the differences in bone loss were likely caused by the exercise type. But since the people and trainers knew who was doing what, there's a small chance they acted differently — so we should be a little careful about how strong the claims are.
0 / 100
- COI disclosureconflicts of interest not disclosed
- Data availabilitydata not shared
- Code availabilitycode not shared
70 / 100
- Randomization+20/20
- Blindingblinding unclear
- Control group+15/15
- Sample size (n=160)+11.0/20
- Follow-up+10/10
100 / 100
100 / 100
- P-values+15/15
- Effect size+20/20
- Confidence intervals+15/15
- 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 570 / 100
Probability of being correct
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
This design can establish causation. Randomization allows causal inference, but lack of blinding introduces potential performance and detection bias, which may slightly weaken causal claims.
No Conflicts
No conflicts of interest identified
No conflicts of interest or funding sources were disclosed in the provided text, and no industry ties or funder involvement were evident.
Independent Analysis Safeguards
- Randomization algorithm generated and maintained by study biostatistician who did not interact with participants
- Assessments conducted by personnel blinded to group assignments
- Intention-to-treat analyses performed using SAS software
- Sensitivity analyses with multiple imputation confirmed results
Although no COI or funding disclosure was provided, the study design includes robust methodological safeguards (blinding, independent randomization, statistical validation) that reduce risk of bias. Absence of funding information is a limitation for full transparency assessment.
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 Leonid Kim MD cite this study, drawing 1 claim from it.
- Very strong evidence
Randomized or controlled trials support this claim, alongside consistent supporting evidence.
Evidence
Authored by
6 researchersIf this is your work, this is how we attribute it on Fit Body Science. Reina Armamento-Villareal is listed as the lead author.