Diagram of the events during a longswing.

<p>In the upper section, body position angle (θ) defined by the z axis, middle grasping hand marker (1) and the center of mass (2). Markers (elbow, shoulder, great trochanter and femoral condyle), joint angles (hip and shoulder), and segmental angles (arm, trunk, and thigh) definitions are exemplified. Additionally, we illustrate the initial position (Pi), final position (Pf) and longswing events (P1, P2, and P3) from the hip (H) and shoulder (S) joints. In the lower section, the joint angular displacement of the shoulder and hip during a longswing of an expert gymnast is represented. For simplicity, H and S events have been represented at the same instant of time for P1-P3 in the upper section.</p

Continuous relative phases obtained from one participant in each group before and after the practice.

<p>Representative continuous relative phases (CRP) of the arm-trunk (AT) and trunk-thigh (TT) coordination obtained from one participant in each novice group (spontaneously-talented, ST, and non-spontaneously-talented, NST) and expert group when they performed a longswing on high bar. CRPs acquired before and after the practice period (pre- and post-practice, respectively) are depicted for the ST and NST groups.</p

Longswing amplitude and inter-joint reversal point changes after the practice period.

<p>Results of the 2 (Group)×2 (Time) ANOVA with repeated measures comparing pre- and post-practice skill global index and coordination variables are depicted in (a) longswing amplitude and (b) inter-joint reversal point P2H-P2S. The expert group (E) mean (solid line) and standard deviation (dashed lines) of these variables are provided for comparison. (★) indicates significant group or time differences. Interaction effects are not presented for simplicity.</p

Positive and negative areas in the continuous relative phase for each group.

<p>Positive and negative areas’ mean and standard deviation for each group (spontaneously-talented, ST, non-spontaneously-talented, NST, and experts) are depicted in: (a) arm-trunk (AT) coordination and (b) trunk-thigh (TT) coordination. Positive and negative areas are calculated over the interval between events of the same joints: P1S-P2S, P2S-P3S, and P3S-Pf in the AT continuous relative phase; and P1H-P2H, P2H-P3H, and P3H-Pf in the TT continuous relative phase. AT coordination mode for the ST during post-practice is highlighted by a circle in order to emphasize the progression toward the expert coordination mode. (★) indicates significant group differences comparing novice (NST and ST) post-practice and experts.</p

Figure 2

Figure

Figure 1

Figure

BIVA studies analysing bioelectrical differences between populations.

<p>BIVA studies analysing bioelectrical differences between populations.</p

Flow chart of study identification and eligibility for the systematic review.

<p>Flow chart of study identification and eligibility for the systematic review.</p

Bioelectrical impedance vector analysis (BIVA) in sport and exercise: Systematic review and future perspectives

<div><p>Background</p><p>Bioelectrical impedance vector analysis (BIVA) is a general concept that includes all methodologies used in the analysis of the bioelectrical vector, whereas the "classic" BIVA is a patented methodology included among these methods of analysis. Once this was clarified, the systematic review of the literature provides a deeper insight into the scope and range of application of BIVA in sport and exercise.</p><p>Objective</p><p>The main goal of this work was to systematically review the sources on the applications of BIVA in sport and exercise and to examine its usefulness and suitability as a technique for the evaluation of body composition, hydration status, and other physiological and clinical relevant characteristics, ultimately to trace future perspectives in this growing area, including a proposal for a research agenda.</p><p>Methods</p><p>Systematic literature searches in PubMed, SPORTDiscus and Scopus databases up to July, 2017 were conducted on any empirical investigations using phase-sensitive bioimpedance instruments to perform BIVA within exercise and sport contexts. The search included healthy sedentary individuals, physically active subjects and athletes.</p><p>Result</p><p>Nineteen eligible papers were included and classified as sixteen original articles and three scientific conference communications. Three studies analysed short-term variations in the hydration status evoked by exercise/training through whole-body measurements, eleven assessed whole-body body composition changes induced by long-term exercise, four compared athletic groups or populations using the whole-body assessment, and two analysed bioelectrical patterns of athletic injuries or muscle damage through localised bioimpedance measurements.</p><p>Conclusions</p><p>BIVA is a relatively new technique that has potential in sport and exercise, especially for the assessment of soft-tissue injury. On the other hand, the current tolerance ellipses of “classic” BIVA are not a valid method to identify dehydration in individual athletes and a new approach is needed. “Specific” BIVA, a method which proposes a correction of bioelectrical values for body geometry, emerges as the key to overcome “classic” BIVA limitations regarding the body composition assessment. Further research establishing standardised testing procedures and investigating the relationship between physiology and the bioelectrical signal in sport and exercise is needed.</p></div

Baseline bioelectrical parameters and vector position of the participants analysed in the studies included in the present review.

<p>Baseline bioelectrical parameters and vector position of the participants analysed in the studies included in the present review.</p