Effect of 11-Week of a Short Functional Core Workout on Lumbar Sagittal Range of Motion in Elite Swimmers: A Randomized Clinical Trial

Lumbar range of movement (ROM) is essential to develop effective movements during underwater undulatory swimming technique. Core exercises are used to improve the strength of the muscles that participate on that technique, nevertheless, they are not designed to improve lumbar ROM. The aim of this study was to examine the effects of an 11-week of 3 functional core exercises for underwater technique on lumbar ROM. Methods: A sample of 57 professional swimmers, 34 males (20.24.2 years) and 23 females (20.73.3yrs), volunteered to complete the study. They were randomly divided into 2 experimental groups (EG1 and EG2) and 1 control group (CG). All subjects underwent the same type of training program in parallel with the EG intervention. EG1 and EG2 fulfilled 3 sets, and 10 repetitions of lumbar flexion and extension exercises at breathing pace, 6 days a week during 11-weeks. EG1 performed the core workout with closed eyes and focusing the attention on the lumbar movement, while EG2 just did the workout only by following the breathing pace. Lumbar flexion (F), extension (E) and total ROM (TROM) were assessed by an electro goniometer on a seated relaxed position over a Swiss ball. Results: Repeated measures ANOVA showed significant differences in the multivariate profiles across groups and over time. F (8, 48) = 3.495, p = 0.002. EG1 had non-significant increases of their lumbar ROM, EG2 had significant increases of the TROM and extension ROM and CG had no changes. Conclusions: The results suggest that repeating maximal lumbar movement at breathing pace, with opened eyes and non-focusing attention on the movement, increases lumbar ROM in sagittal plane.