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William P. Berg and Brian A. Lapp

The purpose of this study was to examine the effect of a practical resistance training program for the lower extremities on mobility in independent, community-dwelling older adults. Twenty-two volunteers with a mean age of 72.9 years underwent two identical pretests 1 month apart. Lower extremity strength, locomotor stability, preferred gait velocity, and step lime in obstacle clearance were assessed. Participants then engaged in an 8-week resistance training program for the lower extremities using adjustable ankle weights. Following a posttest, a repeated-measures ANOVA was used to determine whether changes in strength and mobility when the treatment was interjected differed from when it was not. Results indicated that the training had a limited effect on strength and no effect on mobility. The feasibility of practical resistance training interventions to counteract muscle weakness and associated immobility in independent older adults is discussed.

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Timo Tapio Jaakkola, Arja Sääkslahti, Sami Yli-Piipari, Mika Manninen, Anthony Watt and Jarmo Liukkonen

The purpose of the study was to analyze students’ motivation in relation to their participation in fitness testing classes. Participants were 134 Finnish Grade 5 and 8 students. Students completed the contextual motivation and perceived physical competence scales before the fitness testing class and the situational motivation questionnaire immediately after the class. During the fitness test class, abdominal muscle endurance was measured by curl-up test, lower body explosive strength and locomotor skills by the five leaps test, and speed and agility by the Figure 8 running test. For the fitness testing class, students reported higher scores for intrinsic motivation, identified motivation, and amotivation than in their general physical education program. The result of the path analysis showed physical fitness was positively related to perceived physical competence. In addition, perceived competence was found to be a positive predictor of situational intrinsic motivation, but not of other forms of situational motivation. Significant path coefficients in the model ranged from −.15 to .26.

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Marcos Rodrigo Trindade Pinheiro Menuchi and Lilian Teresa Bucken Gobbi

Locomotion generates a visual movement pattern characterized as optic flow. To explore how the locomotor adjustments are affected by this pattern, an experimental paradigm was developed to eliminate optic flow during obstacle avoidance. The aim was to investigate the contribution of optic flow in obstacle avoidance by using a stroboscopic lamp. Ten young adults walked on an 8m pathway and stepped over obstacles at two heights. Visual sampling was determined by a stroboscopic lamp (static and dynamic visual sampling). Three-dimensional kinematics data showed that the visual information about self-motion provided by the optic flow was crucial for estimating the distance from and the height of the obstacle. Participants presented conservative behavior for obstacle avoidance under experimental visual sampling conditions, which suggests that optic flow favors the coupling of vision to adaptive behavior for obstacle avoidance.

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Ellen M. Kowalski and Claudine Sherrill

This study examined the effects of model type and verbal rehearsal strategy in relation to motor sequencing of boys with learning disabilities (LD). Eighty boys, ages 7 and 8 years, were exposed to four experimental conditions in a 2 × 2 (Model × Verbal Rehearsal Strategy) design. Subjects were randomly assigned to one of four groups: (a) visual-silent model/verbal rehearsal, (b) visual-verbal model/verbal rehearsal, (c) visual-silent model/ no verbal rehearsal, and (d) visual-verbal model/ no verbal rehearsal. The four groups were statistically equal on measures of age, IQ, behavior, learner modality preference, and motor proficiency. Data collected for experimental analysis were generated by the Motor Sequencing Test which measured the ability to model seven locomotor tasks in the correct order. Results revealed that the boys with LD performed significantly better on the motor sequencing test when trained in verbal rehearsal strategy. However, results indicated no significant difference in motor sequencing under visual-silent and visual-verbal model conditions.

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Jin H. Yan and John H. Downing

Tai Chi, an ancieni form of Chinese fitness exercise, affords its participants a variety of physical and psychological benefits. Research has suggested that individuals engaging in Tai Chi exercises improve cardiovascular fitness and motor control while reducing stress, anxiety and depression. Tai Chi is particularly suitable for seniors, who are often at risk for a variety of problems associated with aging (e.g.. arthritis, neurological dysfunction, and general decline of balance, coordination, and locomotor function). Because of its self-paced. nonstressful, and noncompetitive nature, and its ability to afford economy of lime, space, and equipment, Tai Chi presents an effective, functional alternative exercise form for the senior adult population. This article presents the background of Tai Chi practice and introduces several key elements and suggestions for teaching Tai Chi to senior participants. Finally, some selected resources for Tai Chi practice are listed.

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Mikael Scohier, Dominique De Jaeger and Benedicte Schepens

The purpose of this study was to mechanically evoke a triceps surae stretch reflex during the swing phase of running, to study its within-the-step phase dependency. Seven participants ran on a treadmill at 2.8 m·s−1 wearing an exoskeleton capable of evoking a sudden ankle dorsiflexion. We measured the electromyographic activity of the soleus, medial and lateral gastrocnemii just after the perturbation to evaluate the triceps surae stretch reflex. Similar perturbations were also delivered at rest. Our results showed that the stretch reflex was suppressed during the swing phase of running, except in late swing where a late reflex response was observed. At rest, all triceps surae muscles showed an early reflex response to stretch. Our findings suggest that the triceps surae short/medium-latency stretch reflex cannot be evoked during swing phase and thus cannot contribute to the control of the locomotor pattern after aperturbation during this phase.

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Megan A. Kirk and Ryan E. Rhodes

Preschoolers with developmental delay (DD) are at risk for poor fundamental movement skills (FMS), but a paucity of early FMS interventions exist. The purpose of this review was to critically appraise the existing interventions to establish direction for future trials targeting preschoolers with DD. A total of 11 studies met the inclusion criteria. Major findings were summarized based on common subtopics of overall intervention effect, locomotor skill outcomes, object-control outcomes, and gender differences. Trials ranged from 8 to 24 weeks and offered 540–1700 min of instruction. The majority of trials (n = 9) significantly improved FMS of preschoolers with DD, with a large intervention effect (η2 = 0.57–0.85). This review supports the utility of interventions to improve FMS of preschoolers with DD. Future researchers are encouraged to include more robust designs, a theoretical framework, and involvement of parents and teachers in the delivery of the intervention.

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Jason D. Vescovi and Devon H. Frayne

Purpose:

To examine locomotor demands and metabolic-power characteristics of National Collegiate Athletic Association (NCAA) field hockey matches.

Methods:

Using a cross-sectional design, global positioning system (GPS) technology tracked Division I field hockey players from 6 teams during 1 regular-season match (68 player observations). An ANOVA compared locomotor demands and metabolic-power characteristics among positions. Paired t tests compared dependent variables between halves.

Results:

Defenders played 5−6 min more than midfielders, whereas midfielders played 6−7 min more than forwards. Defenders covered less relative distance (98 m/min) than forwards and midfielders (110−111 m/min), as well as more low-intensity running than forwards and less high-intensity running than midfielders. Lower mean metabolic power (9.3 W/kg) was observed for defenders than forwards and midfielders (10.4 W/kg). There was no difference in playing time between halves; however, all 3 positions had a reduction in relative distance (7−9%) and mean metabolic power (8−9%) during the second half.

Conclusions:

Despite more playing time, defenders covered less relative distance and had lower mean metabolic power than other positions. Moderate-intensity, high-intensity, and sprint distance were similar between positions, highlighting the greater relative demands on forwards because they tended to have the least amount of playing time. The reduction of key metrics during the second half was similar among positions and warrants further investigation. These initial results can be used to design position-specific drills or create small-sided games that replicate match demands for NCAA athletes, thus helping establish strategies for developing physiological ability of players at this level.

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Atsumichi Tachibana, Futoshi Mori, Carol A. Boliek, Katsumi Nakajima, Chijiko Takasu and Shigemi Mori

This study investigated developmental aspects of the acquisition of operant-trained bipedal (Bp) standing and Bp walking in the normally quadrupedal (Qp) juvenile Japanese monkey (M. fuscata). Four male monkeys (age: 1.6 to 2.4 years, body weight: 3.3 to 4.6 kg) were initially operantly trained to stand upright on a smooth floor and a stationary treadmill belt (width = 60 cm, walking length = 150 cm). They were then trained to walk bipedally on the moving treadmill belt (speed: 0.4–0.7 m/s). A regular training program (5 days/week; 30–60 min/day) was given to each monkey for the first 40 to 60 days, followed by less intensive training. After the beginning of locomotor training, upright postural stability and Bp walking capability were assessed kinematically for 592, 534, 526, and 537 days on monkeys A, B, C, and D, respectively. Left side- and back-views of the walking monkey were photographed (10 frames/s) and videotaped (250 frames/s). Stick figures of the head, body, and hindlimbs were drawn with reference to ink-marks positioned in front of the ear and over the pivot points of hindlimb joints. All kinematic data were digitized and analyzed using image-analyzing software. After sufficient physical growth and locomotor training, all the monkeys gradually acquired: (a) a more upright and a more stable posture with a constant body axis orientation during Bp locomotion; (b) a more stable and a stronger functional coupling between the body and hindlimb movements with a less anterior (A)-posterior (P) fluctuation of a body axis; (c) a smaller leftward (Lt)-rightward (Rt) displacement of the midline pelvic position, allowing the monkey to walk along a straight course; (d) a more coordinated relationship among hip-knee, knee-ankle, and ankle-metatarsophalangeal (MTP) joints; and finally (e) the acquisition of well-coordinated Bp walking even at high treadmill belt speeds up to 1.5 m/s. All of these results demonstrated the capability of the physically developing monkey to integrate the neural and musculoskeletal mechanisms required for sufficient coordination of upper (head, neck, trunk) and lower (hindlimbs) motor segments so that Bp standing and Bp walking could be elaborated.

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Moeko Ueno, Ichiro Uchiyama, Joseph J. Campos, David I. Anderson, Minxuan He and Audun Dahl

Infants show a dramatic shift in postural and emotional responsiveness to peripheral lamellar optic flow (PLOF) following crawling onset. The present study used a novel virtual moving room to assess postural compensation of the shoulders backward and upward and heart rate acceleration to PLOF specifying a sudden horizontal forward translation and a sudden descent down a steep slope in an infinitely long virtual tunnel. No motion control conditions were also included. Participants were 53 8.5-month-old infants: 25 prelocomotors and 28 hands-and-knees crawlers. The primary findings were that crawling infants showed directionally appropriate postural compensation in the two tunnel motion conditions, whereas prelocomotor infants were minimally responsive in both conditions. Similarly, prelocomotor infants showed nonsignificant changes in heart rate acceleration in the tunnel motion conditions, whereas crawling infants showed significantly higher heart rate acceleration in the descent condition than in the descent control condition, and in the descent condition than in the horizontal translation condition. These findings highlight the important role played by locomotor experience in the development of the visual control of posture and in emotional reactions to a sudden optically specified drop. The virtual moving room is a promising paradigm for exploring the development of perception–action coupling.