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Marcelo Gonçalves Duarte, Glauber Carvalho Nobre, Thábata Viviane Brandão Gomes, and Rodolfo Novelino Benda

Background: Studies related to the motor performance of children have suggested an interaction between organisms and the environment. Although motor development seems to be similar among people, the behavior is specific to the context that people are part of. Thus, the aim of this study was to compare the fundamental motor skill performance between indigenous (IN) and nonindigenous children. Methods: One hundred and thirteen children (43 IN and 70 nonindigenous children) between 8 and 10 years of age underwent the Test of Gross Motor Development—2. Results: A multivariate analysis showed a significant group main effect on both locomotor (p < .01) and object control (p < .01) performance with large and medium effect sizes (ηp2 values = .57–.40, respectively). The IN showed the highest scores for galloping, hopping, leaping, jumping, sliding, striking a stationary ball, stationary dribbling, catching a ball, kicking, and overhand throwing (p < .01) with small to large effect sizes (ηp2 values = .05–.50). Conclusion: The IN presented the highest levels of performance in fundamental motor skills compared with those of nonindigenous children. Most likely, IN have more opportunities for motor development in the environmental context (i.e., villages) where they live.

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Arthur Alves Dos Santos, James Sorce, Alexandra Schonning, and Grant Bevill

This study evaluated the performance of 6 commercially available hard hat designs—differentiated by shell design, number of suspension points, and suspension tightening system—in regard to their ability to attenuate accelerations during vertical impacts to the head. Tests were conducted with impactor materials of steel, wood, and lead shot (resembling commonly seen materials in a construction site), weighing 1.8 and 3.6 kg and dropped from 1.83 m onto a Hybrid III head/neck assembly. All hard hats appreciably reduced head acceleration to the unprotected condition. However, neither the addition of extra suspension points nor variations in suspension tightening mechanism appreciably influenced performance. Therefore, these results indicate that additional features available in current hard hat designs do not improve protective capacity as related to head acceleration metrics.

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Alannah K.A. McKay, Rachel McCormick, Nicolin Tee, and Peter Peeling

This study determined the impact of heat stress on postexercise inflammation and hepcidin levels. Twelve moderately trained males completed three, 60-min treadmill running sessions under different conditions: (a) COOL, 18 °C with speed maintained at 80% maximum heart rate; (b) HOTHR, 35 °C with speed maintained at 80% maximum heart rate; and (c) HOTPACE, 35 °C completed at the average running speed from the COOL trial. Venous blood samples were collected pre-, post-, and 3-hr postexercise and analyzed for serum ferritin, interleukin-6 (IL-6), and hepcidin concentrations. Average HR was highest during HOTPACE compared with HOTHR and COOL (p < .001). Running speed was slowest in HOTHR compared with COOL and HOTPACE (p < .001). The postexercise increase in IL-6 was greatest during HOTPACE (295%; p = .003). No differences in the IL-6 response immediately postexercise between COOL (115%) and HOTHR (116%) were evident (p = .992). No differences in hepcidin concentrations between the three trials were evident at 3 hr postexercise (p = .407). Findings from this study suggest the IL-6 response to exercise is greatest in hot compared with cool conditions when the absolute running speed was matched. No differences in IL-6 between hot and cool conditions were evident when HR was matched, suggesting the increased physiological strain induced from training at higher intensities in hot environments, rather than the heat per se, is likely responsible for this elevated response. Environmental temperature had no impact on hepcidin levels, indicating that exercising in hot conditions is unlikely to further impact transient alterations in iron regulation, beyond that expected in temperate conditions.