A Systematic Review of Isokinetic Muscle Strength in a Healthy Population With Special Reference to Age and Gender

CONTEXT: Despite increasing use of reference values in isokinetic measurements and increasing importance, there is no systematic review of the reference values for lower and upper limb isokinetic muscle strength. OBJECTIVE: A systematic review to analyze studies on the reference values and protocols for the measurement for upper and lower limb isokinetic muscle strength in an untrained and noninjured healthy population. DATA SOURCES: MEDLINE, Scopus, Scielo, and CINAHL (from the earliest date available to June 2020). STUDY SELECTION: Studies that measured a set of reference values for isokinetic muscle strength. STUDY DESIGN: Systematic review. LEVEL OF EVIDENCE: Level 3. DATA EXTRACTION: Two reviewers selected studies independently. Data related to participants characteristics, outcomes of interest, isokinetic parameters, reference values for isokinetic muscle strength, and quality of evidence assessment were systematically reviewed independently by 2 authors. RESULTS: A total of 31 studies met the study criteria. The included studies were used to synthesize the isokinetic muscle strength data according to age-group and sex. We extracted 1845 normative data related to isokinetic strength. Of these, 1181 items referred to lower limbs and 664 items to upper limbs. CONCLUSION: In general, agonist muscle groups are stronger than antagonist muscles, and the men tend to obtain higher strength values than women. The angular velocity varied from 10 to 300 deg/s. The reference values identified can be useful for professionals to obtain during the isokinetic evaluation of the diagnostic parameters of muscle deficiency.