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The aim was to investigate the impact of a specific structured movement activities (SMA) program compared to free play activity (FRP) on the strength, speed, agility, coordination, and balance of motor fitness (MF) in 6-year-old boys and girls. A total of 53 children (24 boys, 29 girls) were randomly allocated to either the SMA group or the FRP group. Both group activities were administered three times a week over a 6-month period. MF variables were assessed before (pre-) and after (post-) using tests: the flamingo balance (FLA), the standing long jump (SLJ), plate tapping (PTT), the obstacle course backwards (OCB), and the shuttle run 4 × 5 m (SRT). At the post-test, the SMA program resulted in significant (p < 0.05) improvements in OCB, PTT, SLJ, and SRT tasks. For FRP, a noteworthy improvement was observed only in OCB (ES = 0.45, p < 0.05). An ANCOVA revealed a significant group × time interaction (F = 21.71-52.41, η2 = 0.258-0.512, p < 0.01) for OCB, PTT, and SRT, favoring SMA over FRP. The present findings suggest that SMA may be more effective than FRP when aiming to develop motor coordination, agility, and speed of movement in children.
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In Batesian mimicry, the mimic gains protection from predators by imitating a noxious model. Some myrmecomorphic species use ants as models as ants have strong defensive capabilities. Ants are highly mobile models, and besides colour, shape, and size, mimics also imitate their movement. Yet, former studies focused mainly on static traits. Here, I tested the hypothesis that artificially increased speed of movement reduces the probability of the mimic being identified. First, images of 14 myrmecomorphic spider species and their models were used for humans to rank their mimetic accuracy. Humans were used as surrogate predators to obtain scores for each mimetic pair. In the second experiment, the effect of movement playback speed on the probability of identification was investigated, again using humans. Videos of mimics were played at different speeds, and the identification probability was recorded. While ants were correctly identified at any playback speed, the identification of myrmecomorphic spiders declined with increasing playback speed. In other words, the latency to correct identification increased with playback speed. Overall, mimics with higher accuracy scores were more difficult to identify while moving. The natural speed of movement of accurate mimics was similar to that of inaccurate ones. Movement is thus an important trait for myrmecomorphic species.
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Mimetismo Biológico , Aranhas , Animais , Movimento , Fenótipo , Comportamento PredatórioRESUMO
Understanding the motor patterns underlying the movement of individuals with Parkinson's disease (PD) is fundamental to the effective targeting of non-pharmacological therapies. This study aimed to analyze the gait pattern in relation to the evolutionary stages I-II and III-IV according to the Hoehn and Yahr (H&Y) scale in individuals affected by PD. The study was conducted with the participation of 37 PD patients with a mean age of 70.09 ± 9.53 years, and of whom 48.64% were women. The inclusion criteria were (1) to be diagnosed with PD; (2) to be in an evolutionary stage of the disease between I and IV: and (3) to be able to walk independently and without any assistance. Kinematic and spatial-temporal parameters of the gait were analyzed. The results showed differences in speed of movement, cadence, stride length, support duration, swing duration, step width, walking cycle duration, and double support time between the stages analyzed. These results confirmed the differences in PD gait pattern between stages I-II and III-IV. Different behaviors of the same variable were recorded depending on whether the right or left side was affected by PD.
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Transtornos Neurológicos da Marcha , Doença de Parkinson , Idoso , Fenômenos Biomecânicos , Feminino , Marcha , Transtornos Neurológicos da Marcha/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Movimento , CaminhadaRESUMO
Despite signs of facial nerve recovery within a few months following face transplantation, speech deficits persist for years. Behavioral speech modifications (e.g., slower-than-normal speaking rate and increased loudness) have shown promising potential to enhance speech intelligibility in populations with dysarthric speech. However, such evidence-based practice approach is lacking in clinical management of speech in individuals with facial transplantation. Because facial transplantation involves complex craniofacial reconstruction and facial nerve coaptation, it is unknown to what extent individuals with face transplant are capable of adapting their motor system to task-specific articulatory demands. The purpose of this study was to identify the underlying articulatory mechanisms employed by individuals with face transplantation in response to speech modification cues at early and late stages of neuromotor recovery. In addition, we aimed to identify speech modifications that conferred improved speech clarity. Participants were seven individuals who underwent full or partial facial vascularized composite allografts that included lips and muscles of facial animation and were in early (~2 months) or late (~42 months) stages of recovery. Participants produced repetitions of the sentence "Buy Bobby a puppy" in normal, fast, loud, and slow speech modifications. Articulatory movement traces were recorded using a 3D optical motion capture system. Kinematic measures of average speed (mm/s) and range of movement (mm3) were extracted from the lower lip (± jaw) marker. Two speech language pathologists rated speech clarity for each speaker using a visual analog scale (VAS) approach. Results demonstrated that facial motor capacity increased from early to late stages of recovery. While individuals in the early group exhibited restricted capabilities to adjust their motor system based on the articulatory demands of each speech modification, individuals in the late group demonstrated faster speed and larger-than-normal range of movement for loud speech, and slower speed and larger-than-normal range of movement for slow speech. In addition, subjects in both groups showed overreliance on jaw rather than lip articulatory function across all speech modifications, perhaps as a compensatory strategy to optimize articulatory stability and maximize speech function. Finally, improved speech clarity was associated with loud speech in both stages of recovery.
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In a predator-prey system, prey species may adapt to the presence of predators with behavioral changes such as increased vigilance, shifting habitats, or changes in their mobility. In North America, moose (Alces alces) have shown behavioral adaptations to presence of predators, but such antipredator behavioral responses have not yet been found in Scandinavian moose in response to the recolonization of wolves (Canis lupus). We studied travel speed and direction of movement of GPS-collared female moose (n = 26) in relation to spatiotemporal differences in wolf predation risk, reproductive status, and time of year. Travel speed was highest during the calving (May-July) and postcalving (August-October) seasons and was lower for females with calves than females without calves. Similarly, time of year and reproductive status affected the direction of movement, as more concentrated movement was observed for females with calves at heel, during the calving season. We did not find support for that wolf predation risk was an important factor affecting moose travel speed or direction of movement. Likely causal factors for the weak effect of wolf predation risk on mobility of moose include high moose-to-wolf ratio and intensive hunter harvest of the moose population during the past century.
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PURPOSE: The locomotor behavior of small fish was characterized under a cell phone-generated radio frequency electromagnetic field (RF EMF). MATERIALS AND METHODS: The trajectory of movement of 10 pairs of guppy (Poecilia reticulate) and 15 pairs of Zebrafish (Danio rerio) in a fish tank was recorded and tracked under the presence of a cell phone-generated RF EMF. The measures were based on spatial and temporal distributions. A time-series trajectory was utilized to emphasize the dynamic nature of locomotor behavior. Fish movement was recorded in real-time. Their spatial, velocity, turning angle and sinuosity distribution were analyzed in terms of F(v,x), P[n(x,t)], P(v), F (θ) and F(s), respectively. In addition, potential temperature elevation caused by a cellular phone was also examined. RESULTS: We demonstrated that a cellular phone-induced temperature elevation was not relevant, and that our measurements reflected RF EMF-induced effects on the locomotor behavior of Poecilia reticulata and Danio rerio. Fish locomotion was observed under normal conditions, in the visual presence of a cell phone, after feeding, and under starvation. Fish locomotor behavior was random both in normal conditions and in the presence of an off-signaled cell phone. However, there were significant changes in the locomotion of the fish after feeding under the RF EMF. CONCLUSIONS: The locomotion of the fed fish was affected in terms of changes in population and velocity distributions under the presence of the RF EMF emitted by the cell phone. There was, however, no significant difference in angular distribution.
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Comportamento Animal/efeitos da radiação , Telefone Celular , Campos Eletromagnéticos/efeitos adversos , Locomoção/efeitos da radiação , Poecilia/fisiologia , Ondas de Rádio/efeitos adversos , Peixe-Zebra/fisiologia , Animais , Análise Espaço-Temporal , TemperaturaRESUMO
OBJECTIVE: To evaluate the long-term preventive impact of strength training on muscle performance in older adults. DESIGN: A 7-year follow-up on a 1-year randomized controlled trial comparing the effects of combined resistance training and aerobic training and whole-body vibration training on muscle performance. SETTING: University training center. PARTICIPANTS: Men and women (N=83; control [CON] group, n=27; strength-training intervention [INT] group, n=56) between 60 and 80 years of age. INTERVENTIONS: The INT group exercised 3 times weekly during 1 year, performing a combined resistance training and aerobic training program or a whole-body vibration training program. The former training program was designed according to American College of Sports Medicine guidelines. The whole-body vibration training program included unloaded static and dynamic leg exercises on a vibration platform. The CON group did not participate in any training program. MAIN OUTCOME MEASURES: Static strength (STAT), dynamic strength at 60°/s (DYN60) and at 240°/s (DYN240), speed of movement at 20% (S20). RESULTS: From baseline to postintervention, muscle performance did not change in the CON group, except for S20 (+6.55%±2.88%, P<.001). One year of strength training increased (P≤.001) STAT (+11.46%±1.86%), DYN60 (+6.96%±1.65%), DYN240 (+9.25%±1.68%), and S20 (+7.73%±2.19%) in the INT group. Between baseline and follow-up, muscle performance decreased (P<.001) in both groups. However, STAT and DYN60 showed a significantly lower loss in the INT group (-8.65%±2.35% and -7.10%±2.38%, respectively) compared with the CON group (-16.47%±2.69% and -15.08%±2.27%, respectively). This positive impact might be due to the preservation of the training-induced gains, given the similar annual decline rates in both groups from postintervention to follow-up. Additionally, in trained participants, aging seems to impact velocity-dependent strength and power more compared with basic strength, as the total losses in DYN240 (CON, -15.93%±2.64%; INT, -11.39%±1.95%) and S20 (CON, -14.39%±2.10%; INT, -13.16%±1.72%) did not differ significantly between the groups. CONCLUSIONS: A 1-year strength-training intervention results in an improved muscle performance in older adults 7 years after their enrollment in the intervention. However, an extensive exercise program cannot attenuate the age-related decline once the intervention stops.