The effect of short-duration sprint interval exercise on plasma postprandial triacylglycerol levels in young men

Abstract

It is well established that regular exercise can reduce the risk of cardiovascular disease, although the most time-efficient exercise protocol to confer benefits has yet to be established. The aim of the current study was to determine the effects of short-duration sprint interval exercise on postprandial triacylglycerol. Fifteen healthy male participants completed two 2 day trials. On day 1, participants rested (control) or carried out twenty 6 s sprints, interspersed with 24 s recovery (sprint interval exercise – 14 min for total exercise session). On day 2, participants consumed a high-fat meal for breakfast with blood samples collected at baseline, 2 h and 4 h. Gas exchange was also measured at these time points. On day 2 of control and sprint interval exercise trials, there were no differences (P < 0.05) between trials in plasma glucose, triacylglycerol, insulin or respiratory exchange ratio (RER). The area under the curve for plasma triacylglycerol was 7.67 ± 2.37 mmol · l^–1.4 h^–1 in the control trial and 7.26 ± 2.49 mmol · l^–1.4 h^–1 in the sprint interval exercise trial. Although the sprint exercise protocol employed had no significant effect on postprandial triacylglycerol, there was a clear variability in responses that warrants further investigation.     

A three-season comparison of match performances among selected and unselected elite youth rugby league players

Abstract

This study compared technical actions, movements, heart rates and perceptual responses of selected and unselected youth rugby league players during matches (under-15 to under-17 age groups). The players’ movements and heart rates were assessed using 5 Hz Global Positioning Systems (GPSs), while their technical actions were analysed using video analysis. The maturity of each player was predicted before each season for statistical control. There were no differences (P > 0.05) between selected and unselected players in the under-15 or the under-17 age group for any variables. However, in the under-16 age group, the selected players (57.1 ± 11.9 min) played for longer than the unselected players (44.1 ± 12.3 min; P = 0.017; ES = 1.08 ± CI = 0.87), and covered more distance (5181.0 ± 1063.5 m cf. 3942.6 ± 1108.6 m, respectively; P = 0.012; ES = 1.14 ± CI = 0.88) and high-intensity distance (1808.8 ± 369.3 m cf. 1380.5 ± 367.7 m, respectively; P = 0.011; ES = 1.16 ± CI = 0.88). Although successful carries per minute was higher in the selected under-15 age group, there were no other differences (P > 0.05) in match performance relative to playing minutes between groups. Controlling for maturity, the less mature, unselected players from the under-16 age group performed more high-intensity running (P < 0.05). Our findings question the use of match-related measurements in differentiating between selected and unselected players, showing that later maturing players were unselected, even when performing greater high-intensity running during matches.     

Application of geographic information technologies to historical landscape reconstruction and military terrain analysis of an American Revolution Battlefield: Preservation potential of historic lands in urbanized settings,Boston, Massachusetts,USA

Through funding from the National Park Service's American Battlefield Protection Program, geographic information technologies were employed to create a high resolution, spatially accurate representation of the 1775 landscape of Boston's Inner Harbor and to conduct a geospatial and temporal assessment of the location, extent, and preservation potential of an American Revolutionary War battlefield and its associated cultural resources. Geographic information technologies provide the tools and methodologies to accurately create digital representations of historical landscapes. These tools enable the visualization and geospatial analysis of landscapes and significant historical events, greatly enhancing the understanding of temporal and spatial interactions between these events and the physical landscape upon which they occurred. Data sources include historical bibliographic and cartographic records, high resolution orthophotographs, constant value raster grids, and LIDAR data. A military terrain model was created utilizing American Battlefield Protection Program's KOCOA system categories, in order to identify defining features of the battlefield. KOCOA is an acronym which stands for Key terrain, Obstacles, Cover and Concealment, Observation and Fields of Fire, and Avenues of Advancement and Withdrawal. The KOCOA analysis provides an established method for identifying critical defining features of the battle and determining the influence of the landscape on the ephemeral battle events. The base map was created utilizing U.S. Navy Coast Survey maps dating from the mid-19th century. A digital elevation model was created to represent the 1775 topography, utilizing LIDAR data and constant value raster layers. The military terrain analysis provided valuable insights into battlefield events and decisions. Defining features of the battle were also identified and mapped. A detailed Environmental Systems Research Institute's ArcGIS Citation Data Model was used to link landscape and KOCOA features to the historical sources they were derived from. A comprehensive source table was created as part of this effort. The results of this investigation have provided a high resolution dataset of Boston's historical landscape during the time of the American Revolution. The geospatial analysis will aid in the development of long-range management strategies for the Chelsea Creek Battlefield and facilitate the assessment of threats to cultural resources posed by both anthropogenic activities and environmental change. The methodologies and interdisciplinary approach will also be applicable to other investigations seeking to recreate historical landscapes within a geographic information system.     

Preschoolers Flexibly Shift Between Speakers' Perspectives During Real-Time Language Comprehension

In communicative situations, preschoolers use shared knowledge, or “common ground,” to guide their interpretation of a speaker's referential intent. Using eye-tracking measures, this study investigated the time course of 4-year-olds’ (n = 95) use of two different speakers’ perspectives and assessed how individual differences in this ability related to individual differences in executive function and representational skills. Gaze measures indicated partner-specific common ground guided children's interpretation from the earliest moments of language processing. Nonegocentric online processing was positively correlated with performance on a Level 2 visual perspective-taking task. These results demonstrate that preschoolers readily use the perspectives of multiple partners to guide language comprehension and that more advanced representational skills are associated with the rapid integration of common ground information.     

Emerging Adults’ Perceptions of Male Circumcision in the United States: Facts,Fictions, and Future Plans

Abstract

Societal perspectives on male circumcision and its implications are not well understood. In this exploratory qualitative study, participants (N?=?34, 7 male, 27 female) enrolled in a human sexuality course were asked to share their perspectives on male circumcision through the development of a written response to open-ended questions. Written responses were analyzed using qualitative thematic analysis to determine the ways in which participants perceive male circumcision, as well as to explore the arguments, contradictions, and rationalizations emerging adults use to justify it. Participants were largely in support of circumcision and believe it to be beneficial in terms of hygiene, esthetics, social acceptability, and tradition. Participants acknowledged the risks of circumcision and rationalized them, indicating they were in favor of the procedure and would circumcise their own sons despite limited knowledge of the benefits and drawbacks. Findings indicate emerging adults do not often discuss male circumcision and do not carefully consider the procedure, perhaps due to the widespread belief that circumcision is a social norm that should not be questioned. Despite this lack of discussion or formal education on the topic, most of the emerging adults did express strong opinions in favor of circumcision based on their personal experiences and social interactions.     

Adolescent Peer Relationship Qualities as Predictors of Long-Term Romantic Life Satisfaction

Adolescent-era predictors of adult romantic life satisfaction were examined in a multimethod, prospective, longitudinal study of 165 adolescents followed from ages 13 to 30. Progress in key developmental tasks, including establishing positive expectations and capacity for assertiveness with peers at age 13, social competence at ages 15 and 16, and ability to form and maintain strong close friendships at ages 16–18, predicted romantic life satisfaction at ages 27–30. In contrast, several qualities linked to romantic experience during adolescence (i.e., sexual and dating experience, physical attractiveness) were unrelated to future satisfaction. Results suggest a central role of competence in nonromantic friendships as preparation for successful management of the future demands of adult romantic life.