Systematic Review
The purpose of the current study is to synthesize the outcomes of investigations reporting the odds of lumbar degenerative disc disease (DDD) in competitive swimmers compared to controls./r/nPubMed, Embase, and Web of Science databases were searched according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines from inception until March 2023 to identify relevant studies evaluating the risk for lumbar DDD associated with swimming./r/nData in the current literature were synthesized for positive imaging findings of DDD at one or more lumbar level in swimmers compared to nonswimmers. Additionally, data regarding prevalence of lumbar disc degeneration and back pain in competitive swimmers were synthesized./r/nFour studies were included in the final analysis. Study quality and risk of bias were deemed adequate. There was significant heterogeneity among studies (I = 0.74) regarding data collected, population of swimmers, sample size, and methods. Therefore, a meta-analysis was not conducted. Three of the four studies included in this review reported that swimmers have increased odds of developing lumbar DDD. Additionally, secondary outcome analysis indicated that swimmers have a higher probability of developing moderate-to-severe back pain./r/nCompetitive swimming appears to be associated with the presence of DDD on advanced imaging and moderate-to-severe back pain. These findings are limited by significant differences in study methodology in the included studies. Although swimming is conventionally considered a low-impact sport, elite swimmers risk developing lower back pain and disc pathology, possibly because training involves unique biomechanics with repetitive rotational and hyperextension/flexion of the spine. Further research investigating risk factors involving biomechanics of swimming on the spine may have important implications for stroke technique, injury prevention, and rehabilitation for swimmers.