Two-dimensional methods have been used to compute trunk kinematic variables (flexion/extension, lateral bend, axial rotation) and X-factor (difference in axial rotation between trunk and pelvis) during the golf swing. Recent X-factor studies advocated three-dimensional (3D) analysis due to the errors associated with two-dimensional (2D) methods, but this has not been investigated for all trunk kinematic variables. The purpose of this study was to compare trunk kinematic variables and X-factor calculated by 2D and 3D methods to examine how different approaches influenced their profiles during the swing. Trunk kinematic variables and X-factor were calculated for golfers from vectors projected onto the global laboratory planes and from 3D segment angles. Trunk kinematic variable profiles were similar in shape; however, there were statistically significant differences in trunk flexion (–6.5 ± 3.6°) at top of backswing and trunk right-side lateral bend (8.7 ± 2.9°) at impact. Differences between 2D and 3D X-factor (approximately 16°) could largely be explained by projection errors introduced to the 2D analysis through flexion and lateral bend of the trunk and pelvis segments. The results support the need to use a 3D method for kinematic data calculation to accurately analyze the golf swing.
Aimée C. Smith, Jonathan R. Roberts, Eric S. Wallace, Pui Kong and Stephanie E. Forrester
Kelly de Jesus, Ross Sanders, Karla de Jesus, João Ribeiro, Pedro Figueiredo, João P. Vilas-Boas and Ricardo J. Fernandes
Coaches are often challenged to optimize swimmers’ technique at different training and competition intensities, but 3-dimensional (3D) analysis has not been conducted for a wide range of training zones.
To analyze front-crawl 3D kinematics and interlimb coordination from low to severe swimming intensities.
Ten male swimmers performed a 200-m front crawl at 7 incrementally increasing paces until exhaustion (0.05-m/s increments and 30-s intervals), with images from 2 cycles in each step (at the 25- and 175-m laps) being recorded by 2 surface and 4 underwater video cameras. Metabolic anaerobic threshold (AnT) was also assessed using the lactate-concentration–velocity curve-modeling method.
Stroke frequency increased, stroke length decreased, hand and foot speed increased, and the index of interlimb coordination increased (within a catch-up mode) from low to severe intensities (P ≤ .05) and within the 200-m steps performed above the AnT (at or closer to the 4th step; P ≤ .05). Concurrently, intracyclic velocity variations and propelling efficiency remained similar between and within swimming intensities (P > .05).
Swimming intensity has a significant impact on swimmers’ segmental kinematics and interlimb coordination, with modifications being more evident after the point when AnT is reached. As competitive swimming events are conducted at high intensities (in which anaerobic metabolism becomes more prevalent), coaches should implement specific training series that lead swimmers to adapt their technique to the task constraints that exist in nonhomeostatic race conditions.
Mark C. Richardson, Andrew Wilkinson, Paul Chesterton and William Evans
injury in female athletes. 9 Individuals with increased landing knee valgus have also shown the same movement patterns in cutting and pivoting tasks, which may further increase their ACL injury risk. 10 A number of previous studies have investigated landing knee valgus using 3-dimensional (3D) analysis
Scott W. Cheatham, Kyle R. Stull, Mike Fantigrassi and Ian Montel
al 25 Clinical trial FAI-CAM impingement N = 26 men Exp (FAI): n = 15 Control: n = 11 Bodyweight squat 3D analysis of hip and pelvic motion Subjects with FAI had no difference in hip motion when compared with controls but had decreased sagittal plane pelvic ROM (14.7° (8.4°) vs 24.2° (6.8°)) when
Kathryn Mills, Aula Idris, Thu-An Pham, John Porte, Mark Wiggins and Manolya Kavakli
difference in the mean of each participant’s peak knee angles as detected by the VR game and 3D analysis as function of the mean of the measures. Solid lines indicate the mean difference (95% CI), or bias, in the VR game. Broken lines and shading indicate the 95% limits of agreement and 95% CI. VR indicates
Gustavo Ramos Dalla Bernardina, Tony Monnet, Heber Teixeira Pinto, Ricardo Machado Leite de Barros, Pietro Cerveri and Amanda Piaia Silvatti
from 1∶2000 to 1∶7000 13 , 14 in air and underwater static conditions, are evidence to suggest that ASC systems perform comparatively with MOCAP systems for such 3D analysis. However, at the present time, no concurrent comparisons between ASC and MOCAP systems have been performed, through simultaneous
Robert MacKenzie, Linda Monaghan, Robert A. Masson, Alice K. Werner, Tansinee S. Caprez, Lynsey Johnston and Ole J. Kemi
contributions in indoor rock climbing . Eur J Appl Physiol . 2007 ; 101 : 293 – 300 . PubMed ID: 17602238 doi:10.1007/s00421-007-0501-0 17602238 10.1007/s00421-007-0501-0 30. Sibella F , Frosio I , Schena F , Borghese NA . 3D analysis of the body center of mass in rock climbing . Hum Mov Sci
Ziemowit Bańkosz and Sławomir Winiarski
, T. ( 1998 ). A qualitative 3D analysis of forehand strokes in table tennis . In A. Lees , I. Maynard , M. Hughes , & T. Reilly (Eds.), Science and racket sports II (pp. 201 – 205 ). London, UK : E. & F.N. Spon . Landlinger , J. , Lindinger , S. , Stöggl , T. , Wagner , H
Maggi M. Calo, Thomas Anania, Joseph D. Bello, Valerie A. Cohen, Siobhan C. Stack, Meredith D. Wells, Barbara C. Belyea, Deborah L. King and Jennifer M. Medina McKeon
excellent reliability. 11 However, 3D biomechanical laboratories are not easily accessible, and it is difficult to screen large numbers of individuals due to the technical requirements of 3D analysis. Two-dimensional (2D) analysis of movement has also been shown to be reliable when evaluating a variety of
Mohammad Reza Pourahmadi, Ismail Ebrahimi Takamjani, Shapour Jaberzadeh, Javad Sarrafzadeh, Mohammad Ali Sanjari, Rasool Bagheri and Morteza Taghipour
during STS. Methods Scope and Boundaries This review intended to examine the methodological considerations for 2-dimensional and 3-D analysis of spinal movements using motion analysis systems. Areas for review included study and participant characteristics, motion analysis system, marker/sensor design