How is the rating of perceived effort reported in anterior cruciate ligament and knee osteoarthritis rehabilitation studies? A scoping review

PURPOSE: To map the methodological aspects of rating of perceived effort (RPE) in resistance exercises during anterior cruciate ligament rehabilitation (ACLR) and knee osteoarthritis (KOA). MATERIALS AND METHODS: A scoping review was conducted by performing systematic search in PubMed, EMBASE, CINAHL, SPORTDiscus, PEDro and CENTRAL databases. Inclusion criteria were longitudinal intervention studies (i.e., randomized clinical trials, quasi-experimental, or case studies) that used RPE to prescribe and monitor the load of resistance exercises targeting the lower limbs in individuals over 18 years with knee osteoarthritis or post-ACL reconstruction. Methodological aspects related to RPE were categorized as yes or no. Then, the percentage of studies reporting each aspect was calculated. RESULTS: Forty-seven studies were included. The methodological aspects "type of scale", "terms used", and "exercise intensity", were frequently reported (37 to 40 studies). However, "familiarization", "anchoring", "instructions", "local vs. whole-body RPE", and "moment of RPE recording" were less reported (1 to 11 studies). CONCLUSION: "Familiarization", "anchoring", "instructions", "local vs. whole-body RPE", and "moment of RPE recording" were not consistently reported in studies, limiting the validity of the method and study replication and making it difficult for clinicians to interpret and apply the method.