Table 1 PICOS inclusion and exclusion criteria for data synthesis

Population

Conducted on community-dwelling older adults aged ≥ 60 years

Intervention

Concentric muscle action

Randomised control trial

Participants must have been instructed to move “as fast as possible” during the concentric phase, or instructions of a similar description

Comparison

Comparison between RT performed whilst being encouraged to concentrically move as fast as possible (MIRT) vs. slow-to-moderate velocity (T-STR)

Studies that reported pre- and post-intervention scores for changes in SPPB score

Outcome

Primary outcome measure was SPPB score, or any individual test derived from the SPPB tests (30-s chair stand (STS), timed-up-and-go (TUG), or balance testing)

Secondary outcomes were dynamic leg press 1RM and knee-extension 1RM, 400-m (400 m) walk, 6-min walk test

Study

A minimum four-week intervention

Between-group design

Published in a peer-reviewed journal

Full-text available in English

Exclusion criteria

Did not specify whether maximal concentric velocity was encouraged

Used concurrent training methods

Did not reply with additional information upon request within 30 days

The article had been retracted

Supplementary/dietary combined intervention

A quasi-experimental research design