Study analysis · AGE · 2015
Slow down the lowering phase for bigger strength gains? This RCT says not so fast.
For older women, slowing the lowering part of a lift to 4.5 seconds did not make them stronger or more functional than normal-speed training, but both groups improved 8–26% relative to baseline.
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 a fair test where people were randomly split into two exercise groups. It can show that both types of exercise helped, but because only a small number of people were studied, we can't be sure if one type is really better than the other.
What’s the bottom line?
Researchers compared two 12-week resistance training programs in older women: one where the lowering (eccentric) phase was slowed to 4.5 seconds, and one with normal 1.5-second phases. Both groups trained twice a week.
How strong is this study?
The study did some things well, like randomly assigning people and having a control group. But it had a small number of people and many dropped out, and the people measuring results might have known which group each person was in. So we should be careful about trusting the results too much.
0 / 100
- COI disclosureconflicts of interest not disclosed
- Data availabilitydata not shared
- Code availabilitycode not shared
59 / 100
- Randomization+20/20
- Blindingblinding unclear
- Control group+15/15
- Sample size (n=26)+2.4/20
- Follow-up+10/10
100 / 100
23 / 100
- P-values+15/15
- Effect sizeno effect size reported
- Confidence intervalsno confidence intervals
- Pre-registrationnot pre-registered
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 547 / 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. Randomized controlled trial design can support causal inference, but small sample (n=26 randomized, 19 analyzed), high dropout (27%), lack of blinding, and absence of eccentric-specific strength measures limit the strength of causal conclusions, especially for claims of no difference (equivalence).
No Conflicts
No conflicts of interest identified
No conflicts of interest or industry funding identified in the provided text.
The provided text lacks a conflict of interest or funding declaration. All listed author affiliations are academic institutions. No industry ties, employment, or financial relationships are disclosed in the available text. Full article may contain additional disclosures not included here.
Key takeaways
- 01
Both groups improved knee extension strength by 24–26% relative to baseline.
- 02
They also improved timed up-and-go by 11–16% relative, 6-m walk by 9–12% relative, stair climbing by 8–13% relative, and chair rising by 15–16% relative.
- 03
There was no significant difference between the two groups.
- 04
Leg press strength did not significantly improve.
- 05
Absolute changes were not reported.
- 06
The improvements are relative to each woman’s starting point; because the study did not report absolute strength or time changes, we cannot say exactly how many seconds faster or how many kilograms stronger they became.
- 07
The key comparison showed no extra benefit from slowing the eccentric phase.
- 08
Some women in the slowed-lowering group reported more muscle pain and discomfort.
Surprising findings
- Slowing the eccentric phase to 4.5 seconds did not add strength or functional benefits over 1.5-second phases.Time under tension is widely promoted as a driver of hypertrophy and strength, so longer eccentric exposure would be expected to help.
- Leg press 1RM did not significantly improve while knee extension 1RM improved 24–26% relative.Both are lower-limb strength tests, so people might expect them to move together.
- Six weeks produced most functional and strength gains, with no additional gains by 12 weeks except stair climbing.Longer training is often assumed to yield continued improvements.
- The eccentric group reported more muscle pain and discomfort despite no extra benefit.More soreness is often taken as a sign of a more effective workout.
Practical takeaways
Older women can use conventional resistance training 2x/week for 6–12 weeks to improve knee extension strength and daily function; slowing the lowering phase to 4.5s is not necessary for extra gains.
Small sample (19 analyzed), no absolute changes reported, 7 dropouts, no blinding described. Results are relative to baseline.
medium-low confidenceIf using slow eccentrics, expect more soreness without guaranteed extra strength benefit when load and volume are matched.
Soreness was self-reported and not quantified; higher eccentric loads might change results.
low-medium confidenceDon't judge progress by leg press alone; knee extension and functional tests may improve even if leg press 1RM doesn't.
This was a small trial; measurement limitations apply.
low-medium confidenceExpect most early gains by 6 weeks; stair climbing may take 12 weeks.
No further gains after 6 weeks for other measures in this study; longer or more intense programs may differ.
low-medium confidenceWhy this study matters
Slow eccentrics: no extra strength or function
In 26 healthy elderly women (67±6 years), 12 weeks of twice-weekly resistance training improved knee extension 1RM by 24–26% relative to baseline and functional tests by 8–16% relative. However, an eccentric-focused group that lowered weights over 4.5 seconds showed no significant between-group differences vs conventional training with 1.5-second phases. Absolute changes were not reported.
Many fitness programs sell slow negatives as a secret to better gains. This trial suggests that with matched load and volume, it may not add anything for older women.
Daily function improves without practicing daily tasks
Both groups improved timed up-and-go by 11–16% relative, 6-m walk by 9–12% relative, stair climbing by 8–13% relative, and chair rising by 15–16% relative to baseline. These tasks were not part of the training, supporting transfer from leg strength to real-life function.
It means getting stronger can make everyday activities easier, even if you never practice them.
Leg press 1RM didn't improve, knee extension did
Leg press 1RM changed by 13.35±12.42% in ETG and 12.19±22.97% in CTG but was not statistically significant. Knee extension 1RM improved significantly by 24–26% relative. The authors suggest 1RM mainly reflects concentric strength and may not capture eccentric adaptations.
Not all strength measures move together; the leg press result is a reminder that testing method matters.
Six weeks may be enough for most gains
Six weeks of training was sufficient for significant improvements in knee extension 1RM, timed up-and-go, 6-m walk, and chair-rising. No further increases occurred between weeks 6 and 12 for these measures; stair climbing improved only after 12 weeks.
It challenges the idea that longer is always better and suggests early neural adaptations drive initial gains.
More soreness, same results
The eccentric-focused group reported muscle pain and discomfort more often, even though load was constant. The authors suggest prolonged eccentric loading may increase muscle damage without extra strength or functional benefit.
If a method makes you sorer but not stronger, it may not be worth the discomfort.
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 compared two 12-week resistance training programs in older women: one where the lowering (eccentric) phase was slowed to 4.5 seconds, and one with normal 1.5-second phases. Both groups trained twice a week.
Research results
Both groups improved knee extension strength by 24–26% relative to baseline. They also improved timed up-and-go by 11–16% relative, 6-m walk by 9–12% relative, stair climbing by 8–13% relative, and chair rising by 15–16% relative. There was no significant difference between the two groups. Leg press strength did not significantly improve. Absolute changes were not reported.
What this means - more context
The improvements are relative to each woman’s starting point; because the study did not report absolute strength or time changes, we cannot say exactly how many seconds faster or how many kilograms stronger they became. The key comparison showed no extra benefit from slowing the eccentric phase. Some women in the slowed-lowering group reported more muscle pain and discomfort.
To assess whether increasing exposure time at the eccentric phase of resistance exercise, using the same training volume and intensity, improves knee extensor strength and functional capacity in elderly women compared with conventional resistance training.
In healthy elderly women, 12 weeks of twice-weekly progressive resistance training improved knee extension 1RM by 24–26% relative to baseline and improved timed up-and-go, 6-m walk, stair-climbing, and chair-rising performance by roughly 8–16% relative to baseline. However, eccentric-focused training with a longer eccentric phase (4.5 s vs 1.5 s) produced no significant between-group differences versus conventional training. Leg press 1RM did not significantly improve. Absolute changes were not reported.
Methods Used
Randomized controlled trial in 26 healthy elderly women (age 67±6 years) assigned to eccentric-focused training (ETG, n=13; concentric 1.5 s, eccentric 4.5 s) or conventional training (CTG, n=13; 1.5 s each phase). Both groups trained twice weekly for 12 weeks at 50–70% of baseline 1RM. Outcomes included leg press and knee extension 1RM and four functional tests. Seven participants dropped out, leaving 9 ETG and 10 CTG for analysis. Blinding was not specified.
Main Finding
Increasing eccentric phase duration using the same volume and intensity did not promote different adaptations in strength or functional capacity compared with conventional resistance training. Both groups improved knee extension 1RM by 24–26% relative to baseline and functional tests by about 8–16% relative to baseline, with no significant between-group differences. Leg press 1RM did not significantly change. Absolute strength and functional changes were not reported.
Confidence Level
Moderate-to-low. Small sample (26 randomized; 19 analyzed), 7 dropouts, no blinding reported, no direct measure of eccentric strength, and 1RM mainly reflects concentric strength. No retraction or corrections noted.
Study Flags
Red Flags
- •Small sample: 26 randomized but only 19 analyzed after 7 dropouts
- •No direct eccentric strength measurement; 1RM mainly tests concentric strength
- •Absolute changes not reported; no blinding described
No biological mechanisms were identified in this study. This may be an epidemiological, observational, or survey-based study that reports associations rather than proposing causal biological pathways.
Surprising Findings
Slowing the eccentric phase to 4.5 seconds did not add strength or functional benefits over 1.5-second phases.
Time under tension is widely promoted as a driver of hypertrophy and strength, so longer eccentric exposure would be expected to help.
Practical Takeaways
Older women can use conventional resistance training 2x/week for 6–12 weeks to improve knee extension strength and daily function; slowing the lowering phase to 4.5s is not necessary for extra gains.
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 547 / 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 is like a fair test where people were randomly split into two exercise groups. It can show that both types of exercise helped, but because only a small number of people were studied, we can't be sure if one type is really better than the other.
The study has a COI section but no disclosure was found. A small penalty has been applied.
Strengths
- Randomized allocation to groups.
- Inclusion of a control group (conventional training).
- Standardized training protocol with familiarization sessions.
Weaknesses
- Small sample size (underpowered for equivalence testing).
- High dropout rate (27%) and per-protocol analysis (no intention-to-treat).
- Blinding of participants and outcome assessors not described.
Methodology
Evidence Keywords
Statistical Reporting
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Researchers compared two 12-week resistance training programs in older women: one where the lowering (eccentric) phase was slowed to 4.5 seconds, and one with normal 1.5-second phases. Both groups trained twice a week.
Research results
Both groups improved knee extension strength by 24–26% relative to baseline. They also improved timed up-and-go by 11–16% relative, 6-m walk by 9–12% relative, stair climbing by 8–13% relative, and chair rising by 15–16% relative. There was no significant difference between the two groups. Leg press strength did not significantly improve. Absolute changes were not reported.
What this means - more context
The improvements are relative to each woman’s starting point; because the study did not report absolute strength or time changes, we cannot say exactly how many seconds faster or how many kilograms stronger they became. The key comparison showed no extra benefit from slowing the eccentric phase. Some women in the slowed-lowering group reported more muscle pain and discomfort.
To assess whether increasing exposure time at the eccentric phase of resistance exercise, using the same training volume and intensity, improves knee extensor strength and functional capacity in elderly women compared with conventional resistance training.
In healthy elderly women, 12 weeks of twice-weekly progressive resistance training improved knee extension 1RM by 24–26% relative to baseline and improved timed up-and-go, 6-m walk, stair-climbing, and chair-rising performance by roughly 8–16% relative to baseline. However, eccentric-focused training with a longer eccentric phase (4.5 s vs 1.5 s) produced no significant between-group differences versus conventional training. Leg press 1RM did not significantly improve. Absolute changes were not reported.
Methods Used
Randomized controlled trial in 26 healthy elderly women (age 67±6 years) assigned to eccentric-focused training (ETG, n=13; concentric 1.5 s, eccentric 4.5 s) or conventional training (CTG, n=13; 1.5 s each phase). Both groups trained twice weekly for 12 weeks at 50–70% of baseline 1RM. Outcomes included leg press and knee extension 1RM and four functional tests. Seven participants dropped out, leaving 9 ETG and 10 CTG for analysis. Blinding was not specified.
Main Finding
Increasing eccentric phase duration using the same volume and intensity did not promote different adaptations in strength or functional capacity compared with conventional resistance training. Both groups improved knee extension 1RM by 24–26% relative to baseline and functional tests by about 8–16% relative to baseline, with no significant between-group differences. Leg press 1RM did not significantly change. Absolute strength and functional changes were not reported.
Confidence Level
Moderate-to-low. Small sample (26 randomized; 19 analyzed), 7 dropouts, no blinding reported, no direct measure of eccentric strength, and 1RM mainly reflects concentric strength. No retraction or corrections noted.
Study Flags
Red Flags
- •Small sample: 26 randomized but only 19 analyzed after 7 dropouts
- •No direct eccentric strength measurement; 1RM mainly tests concentric strength
- •Absolute changes not reported; no blinding described
No biological mechanisms were identified in this study. This may be an epidemiological, observational, or survey-based study that reports associations rather than proposing causal biological pathways.
Surprising Findings
Slowing the eccentric phase to 4.5 seconds did not add strength or functional benefits over 1.5-second phases.
Time under tension is widely promoted as a driver of hypertrophy and strength, so longer eccentric exposure would be expected to help.
Practical Takeaways
Older women can use conventional resistance training 2x/week for 6–12 weeks to improve knee extension strength and daily function; slowing the lowering phase to 4.5s is not necessary for extra gains.
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 547 / 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 is like a fair test where people were randomly split into two exercise groups. It can show that both types of exercise helped, but because only a small number of people were studied, we can't be sure if one type is really better than the other.
The study has a COI section but no disclosure was found. A small penalty has been applied.
Strengths
- Randomized allocation to groups.
- Inclusion of a control group (conventional training).
- Standardized training protocol with familiarization sessions.
Weaknesses
- Small sample size (underpowered for equivalence testing).
- High dropout rate (27%) and per-protocol analysis (no intention-to-treat).
- Blinding of participants and outcome assessors not described.
Methodology
Evidence Keywords
Statistical Reporting
Scoring
How strong is this study?
The study did some things well, like randomly assigning people and having a control group. But it had a small number of people and many dropped out, and the people measuring results might have known which group each person was in. So we should be careful about trusting the results too much.
0 / 100
- COI disclosureconflicts of interest not disclosed
- Data availabilitydata not shared
- Code availabilitycode not shared
59 / 100
- Randomization+20/20
- Blindingblinding unclear
- Control group+15/15
- Sample size (n=26)+2.4/20
- Follow-up+10/10
100 / 100
23 / 100
- P-values+15/15
- Effect sizeno effect size reported
- Confidence intervalsno confidence intervals
- Pre-registrationnot pre-registered
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 547 / 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. Randomized controlled trial design can support causal inference, but small sample (n=26 randomized, 19 analyzed), high dropout (27%), lack of blinding, and absence of eccentric-specific strength measures limit the strength of causal conclusions, especially for claims of no difference (equivalence).
No Conflicts
No conflicts of interest identified
No conflicts of interest or industry funding identified in the provided text.
The provided text lacks a conflict of interest or funding declaration. All listed author affiliations are academic institutions. No industry ties, employment, or financial relationships are disclosed in the available text. Full article may contain additional disclosures not included here.
Standing
The people behind it
The researchers who wrote the study this analysis is built on.
Authored by
7 researchersIf this is your work, this is how we attribute it on Fit Body Science. Caroline Pietá Dias is listed as the lead author.
- Universidade Federal de Ciências da Saúde de Porto Alegre
Cited in 1 claim