Comparison of power training vs traditional strength training on physical function in older adults: a systematic review and meta-analysis

Key points

1. 01Power training means lifting the weight as fast as possible in the lifting phase, then lowering it under control, unlike traditional slow-speed strength training.
2. 02Across 13 RCTs reporting physical function, power training gave a small benefit (SMD 0.30) over traditional strength training, rated low certainty.
3. 03Power itself improved moderately (SMD 0.44), but strength, muscle mass, gait speed, and balance showed no meaningful difference between the two methods.
4. 04Adverse events were low and similar between groups, with no serious events, and adherence was high (about 82%) in both.
5. 05Evidence was downgraded for high risk of bias and small samples (566 total participants), so the modest benefit is uncertain.

How it was conducted

Design

Systematic review with multilevel random-effects meta-analysis of RCTs (PROSPERO CRD42020149015)

Search

MEDLINE, Embase, Cochrane Central, CINAHL, PsycInfo, PEDro, SPORTDiscus to October 2021; 20 RCTs included

Participants

566 healthy community-living older adults from 6 countries (mean age 70.1, 65% women)

Intervention

Power training (fast concentric, controlled eccentric) vs traditional slow-speed strength training, mostly 12 weeks, twice weekly

Outcomes

Physical function and self-reported function (primary); power, strength, muscle mass, gait speed, balance, adverse events (secondary)

Analysis

Standardised mean differences (Hedges g) with cluster-robust 95% CI; risk of bias by Cochrane RoB 2; certainty by GRADE

What they found

• Physical function: power training favoured, SMD 0.30 (95% CI 0.05 to 0.54), I2 = 48%, low certainty (13 RCTs, n=383).
• Self-reported function: SMD 0.38 (95% CI -0.62 to 1.37), not significant, low certainty (3 studies, n=85).
• Power: moderate benefit favouring power training, SMD 0.44 (95% CI 0.21 to 0.66).
• No between-group difference for strength (SMD 0.01, 95% CI -0.14 to 0.16), muscle mass (SMD 0.0004), or gait speed (SMD -0.03), all low certainty.
• Adverse events per 1000 person-sessions were low and similar (3.27 power vs 2.08 traditional) with no serious events; adherence about 82% in both groups.
• RoB 2 rated physical function overall as high risk of bias (5 high, 6 some concerns, 2 low), and GRADE certainty was low for both primary outcomes.

Limitations

• Certainty was low: evidence was downgraded for high risk of bias and imprecision (fewer than 800 participants).
• Most trials were short (12 weeks) with small samples (median around 12 to 13 per group).
• No study objectively tracked lifting velocity to confirm that the power group actually moved faster.
• Only English-language publications were included, and self-reported function rested on just 3 small studies.

Why it matters

For patients

For older adults, doing strength exercises with a fast lifting motion may improve everyday function a little more than lifting slowly, and it appears just as safe.

For clinicians

Power training can be a low-cost option to modestly improve function in older adults, but the certainty is low, so individualise and progress carefully.

For readers

Training muscle power, not just strength, may matter for function in older adults, though larger high-quality trials are still needed.