The assessment of energetic and mechanical parameters in swimming often requires the use of an intermittent incremental protocol, whose step lengths are corner stones for the efficiency of the evaluation procedures.
To analyze changes in swimming kinematics and interlimb coordination behavior in 3 variants, with different step lengths, of an intermittent incremental protocol.
Twenty-two male swimmers performed n × di variants of an intermittent and incremental protocol (n ≤ 7; d1 = 200 m, d2 = 300 m, and d3 = 400 m). Swimmers were videotaped in the sagittal plane for 2-dimensional kinematical analysis using a dualmedia setup. Video images were digitized with a motion-capture system. Parameters that were assessed included the stroke kinematics, the segmental and anatomical landmark kinematics, and interlimb coordination. Movement efficiency was also estimated.
There were no significant variations in any of the selected variables according to the step lengths. A high to very high relationship was observed between step lengths. The bias was much reduced and the 95%CI fairly tight.
Since there were no meaningful differences between the 3 protocol variants, the 1 with shortest step length (ie, 200 m) should be adopted for logistical reasons.
Barbosa is with the Polytechnic Inst of Braganca, Braganca, Portugal. de Jesus, Figueiredo, Vilas-Boas, Fernandes, and Ribeiro are with the Center for Research Education, Innovation, and Intervention in Sport, University of Porto, Portugal. Abraldes is with the Faculty of Sport Sciences, University of Murcia, Spain. Address author correspondence to Tiago Barbosa at email@example.com.