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Survivor of a ship ground in polar regions may have to wait more than five days before being rescued. Therefore, the purpose of this study was to explore cognitive performance during prolonged cold exposure. Core temperature (Tc) and cognitive test battery (CTB) performance data were collected from eight participants during 24 hours of cold exposure (7.5°C ambient air temperature). Participants (recruited from those who have regular occupational exposure to cold) were instructed that they could freely engage in minimal exercise that was perceived to maintaining a tolerable level of thermal comfort. Despite the active engagement, test conditions were sufficient to significantly decrease Tc after exposure and to eliminate the typical 0.5–1.0°C circadian rise and drop in core temperature throughout a 24 h cycle. Results showed minimal changes in CTB performance regardless of exposure time. Based on the results, it is recommended that survivors who are waiting for rescue should be encouraged to engage in mild physical activity, which could have the benefit of maintaining metabolic heat production, improve motivation, and act as a distractor from cold discomfort. This recommendation should be taken into consideration during future research and when considering guidelines for mandatory survival equipment regarding cognitive performance. [ABSTRACT FROM AUTHOR]

Purpose/Background: Proper strengthening of the core and upper extremities is important for muscular health, performance, and rehabilitation. Exercise devices have been developed that attempt to disrupt the center of gravity in order to activate the trunk stabilizing muscles. The objective of this study was to analyze the trunk and shoulder girdle muscle activation with double and single oscillating exercise devices (DOD and SOD respectively) in various planes. Methods: Twelve male subjects performed three interventions using both devices under randomized conditions: single-handed vertical orientation of DOD and SOD to produce 1) medio-lateral oscillation in the frontal plane 2) dorso-ventral oscillation in the sagittal plane and 3) single-handed horizontal orientation for superior and inferior oscillation in the transverse plane. Electromyographic (EMG) activity during the interventions of the anterior deltoid, triceps brachii, biceps brachii, forearm flexors as well as lower abdominal and back stabilizer muscles was collected, and were normalized to maximal voluntary contractions. A two way repeated measures ANOVA (2x3) was conducted to assess the influence of the devices and movement planes on muscle activation. Results: The DOD provided 35.9%, 40.8%, and 52.3% greater anterior deltoid, transverse abdominus (TA)/internal oblique (IO) and lumbo-sacral erector spinae (LSES) activation than did the SOD respectively. Effect size calculations revealed that these differences were of moderate to large magnitude (0.86, 0.48, and 0.61 respectively). There were no significant differences in muscular activation achieved between devices for the triceps brachii, biceps brachii and forearm flexor muscles. Exercise in the transverse plane resulted in 30.5%, 29.5%, and 19.5% greater activation than the sagittal and 21.8%, 17.2%, and 26.3% greater activation than the frontal plane for the anterior deltoid, TA/IO and LSES respectively. Conclusions: A DOD demonstrated greater muscular activity for trunk and shoulder muscle activation but does not provide an advantage for limb activation. Overall, oscillating the devices in the transverse plane provided greater muscular activation of the anterior deltoid, TA/IO and LSES than use of the devices during frontal or sagittal plane movements. [ABSTRACT FROM AUTHOR]

Background: The present pilot study was designed to test the impact of passive acute normobaric hypoxic exposure (PAH) and passive short-term normobaric hypoxic exposure (PSH) conditions on energy expenditure (EE) and substrates utilisation (glucose and lipid oxidation). Methods: Eleven participants have completed the PAH session while the control group (CG) underwent a simulated experimental condition in normobaric normoxic condition. A subset of 6 participants underwent an additional six 3-hour sessions on consecutive days. Metabolic rates were obtained pre- and post-treatments on the morning following an overnight (12 hours) fast in PAH, PSH, and CG groups. Results: The statistical outcomes showed a significant increase in EE for PAH, control, and PSH while a shift in substrate utilization towards lipid sources was only detected for PAH and PSH, respectively. Conclusion: This pilot study showed that passive acute normobaric hypoxic exposure did affect EE and fuel utilization in sedentary overweight males and that further passive normobaric hypoxic exposures (PSH) magnified these metabolic adjustments. These outcomes provide valuable information for further research in the area of hypoxia as a new therapeutic strategy to improve the management of weight loss. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to investigate the biomechanical characteristics and physiological cost of three standardized pulling tasks. 12 female and 17 male subjects participated in the study. The subjects were instructed to pull a load at three different heights (hip, shoulder, eye - anatomical landmarks defined the end of a pull) at a rate of ten pulls per minute, for a period of ten minutes (one hundred total pulls). The pulls were sub-maximal and chosen to represent a task during a typical 8 hour workday. Statistics: ANOVA statistical analyses with Bonferroni pairwise comparisons were performed to determine significance. Results: Statistical significance was obtained for energy expenditure (Ė), sagittal displacement and twisting velocity. Hip pulling Ė was lower than shoulder pulling Ė (p=0.046) and eye pulling Ė (p=0.002) by 7% and 11%, respectively. Hip pulling involves less sagittal displacement than shoulder (p=0.004) and eye (p=0.001) by 37% and 46%, respectively. Finally, twisting velocity at hip (p=0.042) and shoulder (p=0.006) pulling were 30% and 36% higher than twisting velocity at eye pulling. Conclusion: Physiological data combined with biomechanical data provide a comprehensive description of the demands associated with this standardized pulling task. This combined information assists in risk factor identification and intervention design for tasks involving repetitive upper limb movements. [ABSTRACT FROM AUTHOR]

Most studies have examined pacing strategies with cyclical activities (running and cycling). It has been demonstrated that males employ different pacing strategies during repeated maximal voluntary contractions (MVCs) dependent upon a known endpoint. Since different fatiguing mechanisms have been identified between the genders, it is not known if females use comparable pacing strategies. The purpose of this study was to examine if informing female subjects regarding the number of MVCs to perform would affect force and electromyography (EMG). Twenty well-trained females completed 3 fatiguing protocols in a randomized order. In the control condition participants were informed they would perform twelve MVCs and then actually completed twelve. In the unknown condition they were not told how many MVCs to perform but were stopped after twelve. In the deception condition they were initially informed to perform 6 MVCs, but after the 6th MVC they were asked to perform a few more MVCs and were stopped after twelve. During the first 6 MVCs, forces in the deception condition were greater compared to the unknown (p = 0.021, ES = 0.65, 5%) and control (p = 0.022, ES = 0.42, 3%) conditions. No differences were found between conditions in the last 6 MVCs. A main effect for repetitions showed force deficits during the first 6 MVCs (p = 0.000, ES = 1.81, 13%) and last 6 MVCs (p = 0.05, ES = 0.34, 3%). No differences were found between conditions in biceps and triceps EMG. However, EMG decreased during the first 6 MVCs for biceps (p = 0.001, ES = 1.0, 14%) and triceps (p = 0.001, ES = 0.76, 14%) across conditions. No differences were found in the last 6 MVCs. The anticipation of performing fewer MVCs led to increased force, whereas no endpoint led to decreased force production. [ABSTRACT FROM AUTHOR]

Background: Research regarding the Nintendo Wii™ has focused on rehabilitation and balance benefits as well as energy expenditure for games such as boxing and tennis. There is a gap, however, in the literature regarding perceived exertion of the Wii™ compared to other modes of exercise. Research question: The purpose of this laboratory-based study was to compare perceived exertion on the Nintendo Wii™ and two traditional modes of exercise: the treadmill and cycle ergometer. It was expected that the Wii™ would show lower ratings of perceived exertion (RPE) values. Type of study: A repeated measures design was used. Methods: Five healthy males (average age = 21.4 years) and seven females (average age = 22.1 years) completed three 20 minute exercise sessions in random order, one each using the cycle ergometer, the treadmill and the Nintendo Wii Fit Plus™. Exercise intensity was fixed at 65% (± 5 bpm) of each participant's age predicted maximum heart rate. Ratings of perceived exertion and HR were measured every minute. Additionally overall RPE was collected at the end of each trial. Results: Repeated measures analysis of variance confirmed that although exercise intensity was consistent across the three exercise methods, overall RPE was lowest for the Nintendo Wii™ (9.50) followed by the treadmill (9.92) and finally the cycle ergometer (11.08), F(1,11) = 10.17, p<0.01. Conclusions: When compared to certain traditional exercise modalities the Nintendo Wii Fit Plus™ was perceived to require less effort. Therefore, using the Nintendo Wii Fit Plus™ is likely to result in higher exercise adherence rates. [ABSTRACT FROM AUTHOR]