Acute Exercise and Academic Achievement in Middle School Students.

(1) The purpose of this study was to examine the acute effects of aerobic exercise, resistance exercise, and non-exercise on measures of academic achievement and cognition in pre-adolescent students. (2) In a randomized crossover design, sixty-three participants with a mean age of 13.7 ± 0.47 years completed 20 min of aerobic exercise, resistance exercise, or non-exercise with a period of seven days between each bout. Immediately after each bout, participants were tested for academic achievement and cognitive performance. Academic achievement was assessed using standardized, age-appropriate mathematics tests. Cognition was measured using the Dot, Word, and Color tasks of the Stroop Test (Victoria version). (3) Participants scored significantly higher on the mathematics tests (F1,62 = 4.50, p = 0.038) and all elements of the Stroop Test (Dot: F1,62 = 8.14, p = 0.006; Word: F1,62 = 9.90, p = 0.003; Color: F1,62 = 7.57, p = 0.008) following acute resistance exercise as compared to non-exercise. Math test performance was not statistically different between the aerobic and resistance exercise treatments (F1,62 = 0.214, p = 0.645), but participants did perform significantly better on all elements of the Stroop Test following resistance exercise as compared to aerobic exercise (Dot: F1,61 = 25.82, p < 0.001; Word: F1,62 = 14.73, p < 0.001; Color: F1,62 = 20.14, p < 0.001). (4) Resistance exercise acutely influenced academic achievement and cognition in a positive manner. Such results add to the growing body of research that may support an increase in the prescription of varied exercise modalities within school settings for the purposes of improving academic performance and student health.

Acute Effects of 30 Minutes Resistance and Aerobic Exercise on Cognition in a High School Sample.

PURPOSE: The purpose of this study was to determine differences in cognition between acute bouts of resistance exercise, aerobic exercise, and a nonexercise control in an untrained youth sample. METHOD: Ninety-four participants performed 30 min of aerobic exercise, resistance exercise, or nonexercise separated by 7 days each in a randomized crossover design. After each exercise intervention, participants were assessed using 2 cognitive tests. The Dot, Word, and Color elements of the Stroop Test (Victoria version) and Parts A and B of the Trail-Making Test were used to measure cognition. RESULTS: Acute resistance and aerobic exercise resulted in similar improvements over nonexercise in all forms of the Stroop Test. Acute aerobic exercise led to improved performance over nonexercise and resistance exercise in Part B of the Trail-Making Test. Neither exercise intervention showed significant changes in time to complete Part A of the Trail-Making Test. Boys outperformed girls on the Stroop Dot and Color Test following acute aerobic exercise, in the Stroop Dot, Word, and Color Test following acute resistance exercise, and in the Stroop Color Test and Trail-Making Test Part B following nonexercise. CONCLUSIONS: Both acute resistance and aerobic exercise increased measures of cognition over a nonexercise control in untrained high school youth. These findings suggest the merits of acute resistance exercise as an alternative or complement to aerobic activity for educators aiming to increase youth physical activity and cognitive function concurrently.

Accelerometer Derived Activity Counts and Oxygen Consumption between Young and Older Individuals.

The purpose of this investigation was to compare accelerometer activity counts and oxygen consumption between young and elderly individuals. Sixteen young (21.3 ± 2.5 yrs) and sixteen elderly (66.6 ± 2.9 yrs) participants completed 30 minutes of resting oxygen consumption to determine resting metabolic rate and four 6 min walking intensities ranging from 27 to 94 m·min(-1). Resting oxygen uptake was significantly lower for the older participants. Exercise oxygen consumption was significantly higher for the elderly group. There were no significant differences in activity counts between groups at each of the exercise intensities. When using measured resting metabolic rate, activity counts of 824 and 2207 counts·min(-1) were associated with moderate (3 METs) physical activity intensity for the older and young participants, respectively. However, using standard resting metabolic rate (3.5 mL·kg(-1)·min(-1)), activity counts of 784 and 2009 counts·min(-1) were associated with moderate physical activity intensity for the elderly and young participants, respectively. These findings indicate that activity counts are similar across age groups even though the oxygen consumption of exercise is greater among elderly individuals.

Acuity-driven gigapixel visualization.

We present a framework for acuity-driven visualization of super-high resolution image data on gigapixel displays. Tiled display walls offer a large workspace that can be navigated physically by the user. Based on head tracking information, the physical characteristics of the tiled display and the formulation of visual acuity, we guide an out-of-core gigapixel rendering scheme by delivering high levels of detail only in places where it is perceivable to the user. We apply this principle to gigapixel image rendering through adaptive level of detail selection. Additionally, we have developed an acuity-driven tessellation scheme for high-quality Focus-and-Context (F+C) lenses that significantly reduces visual artifacts while accurately capturing the underlying lens function. We demonstrate this framework on the Reality Deck, an immersive gigapixel display. We present the results of a user study designed to quantify the impact of our acuity-driven rendering optimizations in the visual exploration process. We discovered no evidence suggesting a difference in search task performance between our framework and naive rendering of gigapixel resolution data, while realizing significant benefits in terms of data transfer overhead. Additionally, we show that our acuity-driven tessellation scheme offers substantially increased frame rates when compared to naive pre-tessellation, while providing indistinguishable image quality.

Interactive visibility retargeting in VR using conformal visualization.

In Virtual Reality, immersive systems such as the CAVE provide an important tool for the collaborative exploration of large 3D data. Unlike head-mounted displays, these systems are often only partially immersive due to space, access, or cost constraints. The resulting loss of visual information becomes a major obstacle for critical tasks that need to utilize the users' entire field of vision. We have developed a conformal visualization technique that establishes a conformal mapping between the full 360° field of view and the display geometry of a given visualization system. The mapping is provably angle-preserving and has the desirable property of preserving shapes locally, which is important for identifying shape-based features in the visual data. We apply the conformal visualization to both forward and backward rendering pipelines in a variety of retargeting scenarios, including CAVEs and angled arrangements of flat panel displays. In contrast to image-based retargeting approaches, our technique constructs accurate stereoscopic images that are free of resampling artifacts. Our user study shows that on the visual polyp detection task in Immersive Virtual Colonoscopy, conformal visualization leads to improved sensitivity at comparable examination times against the traditional rendering approach. We also develop a novel user interface based on the interactive recreation of the conformal mapping and the real-time regeneration of the view direction correspondence.

Conformal Visualization for Partially-Immersive Platforms.

Current immersive VR systems such as the CAVE provide an effective platform for the immersive exploration of large 3D data. A major limitation is that in most cases at least one display surface is missing due to space, access or cost constraints. This partially-immersive visualization results in a substantial loss of visual information that may be acceptable for some applications, however it becomes a major obstacle for critical tasks, such as the analysis of medical data. We propose a conformal deformation rendering pipeline for the visualization of datasets on partially-immersive platforms. The angle-preserving conformal mapping approach is used to map the 360°3D view volume to arbitrary display configurations. It has the desirable property of preserving shapes under distortion, which is important for identifying features, especially in medical data. The conformal mapping is used for rasterization, realtime raytracing and volume rendering of the datasets. Since the technique is applied during the rendering, we can construct stereoscopic images from the data, which is usually not true for image-based distortion approaches. We demonstrate the stereo conformal mapping rendering pipeline in the partially-immersive 5-wall Immersive Cabin (IC) for virtual colonoscopy and architectural review.

Real-time volume-based ambient occlusion.

Real-time rendering can benefit from global illumination methods to make the 3D environments look more convincing and lifelike. On the other hand, the conventional global illumination algorithms for the estimation of the diffuse surface interreflection make heavy usage of intra- and interobject visibility calculations, so they are time-consuming, and using them in real-time graphics applications can be prohibitive for complex scenes. Modern illumination approximations, such as ambient occlusion variants, use precalculated or frame-dependent data to reduce the problem to a local shading one. This paper presents a fast real-time method for visibility sampling using volumetric data in order to produce accurate inter- and intraobject ambient occlusion. The proposed volume sampling technique disassociates surface representation data from the visibility calculations, and therefore, makes the method suitable for both primitive-order or screen-order rendering, such as deferred rendering. The sampling mechanism can be used in any application that performs visibility queries or ray marching.

Relationship between running velocity of 2 distances and various lactate parameters.

PURPOSE: The purpose of this study was to determine the relationship between various lactate-threshold (LT) definitions and the average running velocity during a 10-km and a 21.1-km time trial (TT). METHODS: Thirteen well-trained runners completed an incremental maximal exercise test, a 10-km TT, and a 21.1-km TT on a motorized treadmill. Blood samples were collected through a venous catheter placed in an antecubital vein. Pearson's correlation coefficients were used to determine the relationship between the running velocity at the different LT definitions and the average running velocity during each TT. A dependent t test was used to determine statistical differences for the mean lactate response between the 2 running distances. RESULTS: The LT(Dmax), the point on the regression curve that yielded the maximal perpendicular distance to the straight line formed by the 2 endpoints, was the LT definition with the highest correlation for both 10-km (r = .844) and 21.1-km TTs (r = .783). The velocity at the LT(Dmax) was not, however, the velocity closest to the performance velocity for either distance. The mean running velocity at each LT was significantly different and tended to overestimate the mean TT performance velocities. The mean lactate concentration during the 10-km TT (3.52 + or - 1.58 mmol) was significantly higher than during the 21.1-km TT (1.86 + or - 0.90 mmol). CONCLUSION: These results indicate that a single LT point cannot be reliably associated with different running distances. Furthermore, these data suggest that a different methodology for estimating the LT that considers individual responses might be required for different running distances.