Differences in swimming smoothness between elite and non-elite swimmers

Abstract

The aim of the study was to investigate whether jerk cost (JC) can discriminate between swimming levels. Nine elite and nine non-elite swimmers swam a 50-m front-crawl sprint wearing a 3D accelerometer on their back between the inferior angles of the scapulae. Lap times and JC were calculated from the acceleration signal and compared between groups and between swimmers within a group. The elite swimmers swam significantly faster lap times than the non-elite swimmers (p < 0.001). They did so with significantly lower levels of JC compared to the non-elite swimmers (p = 0.005). Furthermore, a stepwise multiple linear regression showed JC accounted for 32.9% of the variation in lap time of the elite swimmers. These results indicate that it is possible to discriminate elite from non-elite swimmers using JC: elite swimmers swim with lower JCs than non-elite swimmers. Additionally, swimming at higher speed is associated with more accelerations and decelerations in both elite and non-elite swimmers, which is reflected by higher JCs and lower smoothness. In sum, JC provides an index of swimming technique that is easy to use in training practice. ARTICLE HISTORY

Intracycle Velocity Variation in Swimming: A Systematic Scoping Review

“…After the seventy-four full texts were screened, one was excluded by type [ 50 ], six by exposure [ 51 , 52 , 53 , 54 , 55 , 56 ], seven by outcomes [ 57 , 58 , 59 , 60 , 61 , 62 , 63 ] and one by participant [ 64 ] eligibility criteria. Reference list analysis revealed 31 studies on the topic as potentially meeting the inclusion criteria, with full-text analysis excluding 10 articles by type [ 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 ], 2 by exposure [ 75 , 76 ] and 8 by outcomes [ 18 , 77 , 78 , 79 , 80 , 81 , 82 , 83 ]. Seven additional studies from snowballing citation tracking process were deemed eligible for inclusion, and all were included [ 29 , 84 , 85 , 86 , 87 , 88 , 89 ].…”

Profiling of elite male junior 50 m freestyle sprinters: Understanding the speed‐time relationship

“…26,27 In the remaining sections (S15-25 m, S25-35 m, S35-45 m, and S45-50 m), the literature reports significant differences in swimming speed during the 50 m freestyle competition between elite and non-elite swimmers. 28 However, there is no information about swimmers within the same competitive level or at least a more homogeneous group. Our data show that such difference in swimming speed was maintained along the race.…”

The role of the biomechanics analyst in swimming training and competition analysis

“…Regarding athlete free swim ability, Ganzevles et al (2019) demonstrated the usefulness of a tri-axial accelerometer for quantifying jerk cost and swimmer smoothness where findings offer insight into refined flow and coordination patterns of elite swimmers. Intra-stroke velocity and intra-cyclic stroke variations measured with inertial measurement units provide promising possibilities into body segment coordination and sequence timing (Worsey et al, 2018).…”