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Three-dimensional kinematics and kinetics for a double pendulum model golf swing were determined for 6 subjects, who were filmed by two phase-locked Photosonics cameras. The film was digitally analyzed. Abdel-Aziz and Karara's (1971) algorithm was used to determine three-dimensional spatial coordinates for the segment endpoints. Linear kinematic and kinetic data showed similarities with previous studies. The orientation of the resultant joint force at the wrists was in the direction of motion of the club center of gravity for most of the downswing. Such an orientation of the force vector would tend to prevent wrist uncocking. Indeterminate peak angular velocities for rotations about the X axis were reported. However, these peaks were due to computational instabilities that occurred when the club was perpendicular to the YZ plane. Furthermore, the motion of the club during the downswing was found to be nonplanar. Wrist uncocking appeared to be associated with the resultant joint torque and not the resultant joint force at the wrists. Torques reported in this study were consistent with those reported by Vaughan (1981).

This study investigated cardiac and electrodermal responses in competitive gymnasts differing in levels of trait anxiety and repression. The research strategy was to seek differences in tonic and phasic physiological measures that occurred in association with differences in state and/or trait anxiety levels, and then to investigate whether similar differences were associated with differences in levels of repression. Two task conditions were employed: A resting baseline session was counterbalanced with an imagery session in which subjects were requested to image their current team routine in real time. For half of each session, subjects were instructed to either count (relevant) stimuli or ignore (irrelevant) stimuli. The results established a number of psychophysiological differences between groups differing on state and trait anxiety. Similar differences as a result of repression were not obtained, raising questions about the validity of the construct of “repression” in this context. There were some small effects, however, suggesting that repression may affect components of attentional processing in different situations.

Eight international baseball pitchers were filmed in a laboratory while throwing from a pitching rubber attached to a Kistler force platform. Following a warm-up, all subjects threw fastballs (FB) until two strike pitches were assessed by an umpire positioned behind the catcher for both wind-up and set pitching techniques. Subjects then followed the same procedures for curveball pitches (CB). Both vertical (Z) and horizontal (Y) ground reaction force (GRF) data were recorded. A shutter correlation pulse was encoded so the temporal data from the film could be synchronized with the kinetic data from the force platform. Analysis of variance was used to analyze differences in force data at selected points in both pitching actions for both techniques. Vertical and horizontal GRFs increased from the first balance position to maximum levels at the cocked position for both techniques. Nonsignificant changes in GRF then occurred between the cocked position and front-foot landing. The Z GRFs were similar throughout the pitching action but higher in magnitude for the CB compared to the FB. Mean resultant forces were similar for the three fastest FB pitchers when compared to the three slowest pitchers. However, the slower group produced their peak resultant force earlier in the action, thus reducing the ability to drive over a stabilized front leg.

Three-dimensional (3-D) high speed photography was used to record the fastball (FB) and curveball (CB) actions of six members of the Australian National pitching squad. The direct linear transformation (DLT) method of motion analysis for 3-D space reconstruction from 2-D images was used to record the movement of selected anatomical features. Laterally positioned phase-locked cameras operating at 200 fps and a front-on camera operating at 300 fps were used to record the pitching action. Mean pitching velocities for the FB and the CB were recorded. A kinematic analysis of the two pitching motions from the first balance point following the completion of the pump and pivot to follow through are presented. The actions are very similar for the two pitches, as would be expected if disguised to confuse the batter. Minor differences were noted, however, for stride length, forearm action prior to release, and wrist action at release.

While traditional approaches to dietary analysis in athletes have focused on total daily energy and macronutrient intake, it is now thought that daily distribution of these parameters can also influence training adaptations. Using 7-day food diaries, we quantified the total daily macronutrient intake and distribution in elite youth soccer players from the English Premier League in U18 (n = 13), U15/16 (n = 25) and U13/14 squads (n = 21). Total energy (43.1 ± 10.3, 32.6 ± 7.9, 28.1 ± 6.8 kcal·kg^-1·day^-1), CHO (6 ± 1.2, 4.7 ± 1.4, 3.2 ± 1.3 g·kg^{- 1}·day^-1) and fat (1.3 ± 0.5, 0.9 ± 0.3, 0.9 ± 0.3 g·kg-¹·day^-1) intake exhibited hierarchical differences (p < .05) such that U13/14 > U15/16 > U18. In addition, CHO intake in U18s was lower (p < .05) at breakfast, dinner and snacks when compared with both squads but no differences were apparent at lunch. Furthermore, the U15/16s reported lower relative daily protein intake than the U13/14s and U18s (1.6 ± 0.3 vs. 2.2 ± 0.5, 2.0 ± 0.3 g·kg^-1). A skewed distribution (p < .05) of daily protein intake was observed in all squads, with a hierarchical order of dinner (~0.6 g·kg^-1) > lunch (~0.5 g·kg^-1) > breakfast (~0.3 g·kg^-1). We conclude elite youth soccer players do not meet current CHO guidelines. Although daily protein targets are achieved, we report a skewed daily distribution in all ages such that dinner > lunch > breakfast. Our data suggest that dietary advice for elite youth players should focus on both total daily macronutrient intake and optimal daily distribution patterns.

The daily distribution of macronutrient intake can modulate aspects of training adaptations, performance and recovery. We therefore assessed the daily distribution of macronutrient intake (as assessed using food diaries supported by the remote food photographic method and 24-hr recalls) of professional soccer players (n = 6) of the English Premier League during a 7-day period consisting of two match days and five training days. On match days, average carbohydrate (CHO) content of the prematch (<1.5 g·kg^-1 body mass) and postmatch (1 g·kg^-1 body mass) meals (in recovery from an evening kick-off) were similar (p > .05) though such intakes were lower than contemporary guidelines considered optimal for prematch CHO intake and postmatch recovery. On training days, we observed a skewed and hierarchical approach (p < .05 for all comparisons) to protein feeding such that dinner (0.8 g·kg^-1)>lunch (0.6 g·kg^-1)>breakfast (0.3 g·kg^-1)>evening snacks (0.1 g·kg^-1). We conclude players may benefit from consuming greater amounts of CHO in both the prematch and postmatch meals so as to increase CHO availability and maximize rates of muscle glycogen resynthesis, respectively. Furthermore, attention should also be given to ensuring even daily distribution of protein intake so as to potentially promote components of training adaptation.

The purpose of this study was to develop and evaluate an alternative method for determining the position of the anterior superior iliac spine (ASIS) during cycling. The approach used in this study employed an instrumented spatial linkage (ISL) system to determine the position of the ASIS in the parasagittal plane. A two-segment ISL constructed using aluminum segments, bearings, and digital encoders was tested statically against a calibration plate and dynamically against a video-based motion capture system. Four well-trained cyclists provided data at three pedaling rates. Statically, the ISL had a mean horizontal error of 0.03 ± 0.21 mm and a mean vertical error of −0.13 ± 0.59 mm. Compared with the video-based motion capture system, the agreement of the location of the ASIS had a mean error of 0.30 ± 0.55 mm for the horizontal dimension and −0.27 ± 0.60 mm for the vertical dimension. The ISL system is a cost-effective, accurate, and valid measure for two-dimensional kinematic data within a range of motion typical for cycling.

In an attempt to better identify and inform the energy requirements of elite soccer players, we quantified the energy expenditure (EE) of players from the English Premier League (n = 6) via the doubly labeled water method (DLW) over a 7-day in-season period. Energy intake (EI) was also assessed using food diaries, supported by the remote food photographic method and 24 hr recalls. The 7-day period consisted of 5 training days (TD) and 2 match days (MD). Although mean daily EI (3186 ± 367 kcals) was not different from (p > .05) daily EE (3566 ± 585 kcals), EI was greater (p < .05) on MD (3789 ± 532 kcal; 61.1 ± 11.4 kcal.kg^-1 LBM) compared with TD (2956 ± 374 kcal; 45.2 ± 9.3 kcal.kg^-1 LBM, respectively). Differences in EI were reflective of greater (p < .05) daily CHO intake on MD (6.4 ± 2.2 g.kg^-1) compared with TD (4.2 ± 1.4 g.kg^-1). Exogenous CHO intake was also different (p < .01) during training sessions (3.1 ± 4.4 g.h^-1) versus matches (32.3 ± 21.9 g.h^-1). In contrast, daily protein (205 ± 30 g.kg^-1, p = .29) and fat intake (101 ± 20 g, p = .16) did not display any evidence of daily periodization as opposed to g.kg^-1, Although players readily achieve current guidelines for daily protein and fat intake, data suggest that CHO intake on the day before and in recovery from match play was not in accordance with guidelines to promote muscle glycogen storage.