Nicola Fragnito

Three-dimensional analysis of active head and cervical spine range of motion: effect of age in healthy male subjects.

OBJECTIVE To assess the effect of age on active head-cervical range of motion in healthy men. DESIGN Three-dimensional cervical motion ranges and patterns were measured in 70 men. BACKGROUND The effect of age on cervical range of motion is still discussed. METHOD Twenty adolescent (mean age 16 year), 30 young adult (mean age 23 year), and 20 mid-aged (mean age 37 year) men performed maximal head and cervical spine flexion-extension, lateral bending, and axial rotation. Movements were detected using a digital optoelectronic instrument. Maximum head-cervical spine and thoracic motions were separated. RESULTS Flexion and extension were larger in the adolescents and young adults (130-132 degrees ) than in the mid-aged men (117 degrees ). Thoracic movement increased as a function of age. Lateral bending was symmetric, associated with head-cervical rotation and extension, and larger in adolescents (85 degrees ) than in young (77 degrees ) and mid-aged adults (79 degrees ). Axial rotation was symmetric, associated with flexion-extension and lateral bending, and similar in the three age groups (respectively, 160 degrees, 155 degrees, 153 degrees ). CONCLUSIONS Active head-cervical range of motion reduced between 15 and 45 years of age in men. Relevance The present data can be used as a reference for cervical range in motion in men between 15 and 45 years.

THE REPEATABILITY OF CHOKU-TSUKI AND OI-TSUKI IN TRADITIONAL SHOTOKAN KARATE: A MORPHOLOGICAL THREE-DIMENSIONAL ANALYSIS

The aim of the study was to quantify the repeatability of the displacement of selected body landmarks while performing two different basic karate attacks. Seven karateka (three men, four women) with different levels of training and knowledge of karate were filmed with an optoelectronic computerized instrument (sampling rate 100 Hz) that allows the three-dimensional reconstruction of the movements of selected body landmarks. Thirteen landmarks (head, hips, upper and lower limbs) were analyzed while performing 10 repetitions each of choku-tsuki (straight punch) and oi-tsuki (lunge punch). For each karateka and punch, the average time of execution was calculated, and the standard deviations of each of the three spatial coordinates x, y, z were computed for each landmark. A total standard deviation of the single karateka and punch was also calculated. For all karateka, the execution of oi-tsuki took longer than the execution of choku-tsuki. For both punches and almost all landmarks, the largest repeatability (smallest standard deviation) was found in the vertical direction, while the smallest was found in the anteroposterior direction (direction of movement). In all karateka, oi-tsuki had a total standard deviation about 3 to 6 times larger than that measured during the performance of choku-tsuki. On average, women had a larger repeatability than men. The method employed in the current study allowed the quantitative analysis of the repeatability of two basic attacks in Shotokan karate by using a landmark-based approach. The method could offer valuable help to karateka during training indicating which parts of the body do not repeat a selected movement with sufficient accuracy, thus assisting in the achievement of the most correct body form.

INFLUENCE OF TRAINING ON MAINTENANCE OF EQUILIBRIUM ON A TILTING PLATFORM

To assess the influence of training on the maintenance of equilibrium on a tilting platform, 13 young healthy male athletes aged 19 to 33 years were randomly divided into experimental (n = 7) and control (n = 6) groups. Two experimental sessions were performed before and after a specific 4-wk. training by the experimental group. Subjects stood upright on a tilting platform. The athletes were asked to maintain the platform as horizontal as possible during a 30-sec. test. The three-dimensional movements of the platform versus the ground were recorded by using a computerized optoelectronic digitiser. The platform plane was calculated and its directrix computed. The area of oscillation and instantaneous angular velocity of the directrix at standardized height were calculated. In both groups the area of oscillation and the angular velocity were reduced in Session 2, but the reduction was significant only in the experimental group. Specific training can significantly improve skill at maintaining equilibrium in young healthy sport performers.

Harmonic analysis of footprint symmetry in healthy adolescents.

In the present study, the within-subject normal symmetry of footprint shape and size was analyzed from a mathematical standpoint. On the standardized left and right footprints of 83 adolescents (46 boys, 37 girls) aged 12-15 years (mean 13 years), the outline of each foot excluding the toes was identified and automatically digitized by a computerized video analyzer. Only those subjects with both left and right continuous footprints were further analyzed (36 boys, 26 girls). The footprint area was computed. The footprint shape, independent of its size, was quantified using the elliptic Fourier analysis with a 20-harmonic truncation. The symmetry in shape was quantified on an intra-subject basis by calculating a morphological distance D between the mathematical reconstructions of the left and right footprints of each subject. Symmetry in size was assessed by right-to-left area ratio. Subjects were grouped for sex, and the mean values computed. Mean footprint area was significantly larger in boys than in girls (p < 0.05). Asymmetry in size (area ratio) was 1.01 in girls, 1 in boys. Within-subject symmetry in footprint shape appeared high, with mean morphological distances of 5.95 in girls, and 6.06 in boys. No consistent associations between footprint symmetry and age, height and body weight, or shoe size were found. The mean size-independent shapes of the male and female left and right footprints were also calculated. Together with the analysis of individual asymmetry, they could be used as quantitative parameter in clinical diagnosis.

Repeatability of Choku-Tsuki and Oi-Tsuki in Shotokan Karate: A 3-Dimensional Analysis with Thirteen Black-Belt Karateka

13 black-belt karateka performed two different standardized counter-offensive techniques. The trajectories of selected body landmarks were studied by using a computerized image analyzer that allows a 3-dimensional reconstruction of standardized movements. The repeatability of both karate techniques was quantified for each participant. Analysis confirmed that more experienced karateka obtained the best repeatability, as already demonstrated in a preliminary study conducted with a smaller sample of less experienced participants.