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The purpose of this study was to 1) compare the body composition values of an active group of breast cancer survivors (BCS) determined by dual X-ray absorptiometry (DXA) and anthropometry, and 2) compare the bone mineral density of the upper thoracic region to assess the effect of tumor burden on bone health.
Design and Methods
Forty (n=40) breast cancer survivors from a local competitive Dragon Boat Team were measured as part of team assessments. ANOVA with Dunn’s post-hoc testing was used to compare results of DXA, body density, and body composition estimated from anthropometry. Bland-Altman testing and correlational analysis were calculated.
Percentage of fat measure by DXA was significantly higher than values used to estimate body fat from skinfold measures or from body density equations (DXA 41.1±6.0% vs. 3-site skinfolds 28.8±4.9%, 4-site skinfolds, 22.1±4.1%, skinfold and body density, 31.8±9.4%, respectively, p<0.05). Post-hoc testing revealed that all values were significantly different and the strongest correlation
with DXA was skinfolds at three sites was r=0.81. Regional (upper thoracic) bone mineral density was not significantly different based on tumor side diagnosis (breast cancer diagnosis side versus healthy, 0.971±0.198 vs. 0.988±0.190 gm*cc-1). Anthropometry and bilateral bone mineral density characteristics are presented to serve as a comparative sample of BCS for future studies.
As body composition is an important factor in long-term cancer survivorship, we found the use of skinfold measures inadequate to accurately determine percentage of fat in this group of active female BCS. As a result, recommendations aimed at achieving an ideal body composition based solely on anthropometry would have grossly underestimated fat mass, which may lead to overall clinically poorer outcomes.
Breast cancer; Body composition; Percentage fat; Bone mineral density.
The hindlimb suspended (HLS) rat model has been used in land-based research to evaluate effects of simulated microgravity. Previous research demonstrated that 2-4 weeks of HLS reduced vasoconstrictive responses of aortic, mesenteric, and femoral arterial rings to phenylephrine (PHE) while acute exposure to hyperoxia amplified constrictive responses to PHE. The purpose of this study was to determine if hyperbaric oxygen treatment (HBO) during HLS would reverse the attenuation of the vasoconstrictive response.
Five-month-old male Sprague Dawley rats were randomly divided into aging controls (AC), AC-HBO, HLS, and HLS-HBO. Groups receiving HBO (AC-HBO; HLS-HBO) were placed in a cage that was fitted for the animal hyperbaric chamber to maintain HLS. HBO groups received 24 treatments, once a day, 6 d/week using a wound care protocol. The chamber was flushed with 100% oxygen, compressed over 10 min to 2.5 atmospheres absolute (ATA) (22.5 psig), a 90-minute treatment, then a 10 min decompression. After 28 d of HLS, animals were sacrificed under isoflurane anesthesia and thoracic aorta segments isolated. Relaxation of aortic rings was measured in response to acetylcholine (ACh) and sodium nitroprusside (SNP) after pre-constriction with PHE (3×10-7). Constriction of aortic rings was also determined in response to increasing concentrations of PHE. All drugs were administered cumulatively in vessel baths at 10-10-10-4 M. Data were analyzed using four-parameter (i.e., minimum, maximum, EC50, slope) nonlinear regression, and groups compared using 2×2 ANOVA with HBO and HLS as main effects.
Responses to ACh and SNP were not affected by HLS or HBO. However, in response to PHE, there was a decrease in maximum vasoconstriction in HLS compared to controls (44.7±7.3% vs 82.4±6.0%, respectively, p≤0.05) and in HBO compared to controls (48.5±6.5% vs 78.6±6.8%, p≤0.05).
These results indicate that PHE-induced constriction of thoracic aorta is decreased after HLS. HBO did not reverse HLS-induced reductions in contractile responses; instead, HBO independently reduced PHE-stimulated constriction of aortic segments. This suggests that HBO may be useful in conditions where constriction is enhanced, such as diabetes.
Hyperbaric oxygen; Vascular reactivity; Hindlimb suspension.
In the realm of competitive athletics, numerous variables have been examined for predictive utility with respect to player selection/development and outcomes on the field. Notwithstanding important advances, the current predictors only account for a modest amount of variance in outcomes of relevance in the National Football League (NFL).
The primary objective of this study was to investigate the predictive validity of a new measure of athletic intelligence, the Athletic Intelligence Quotient (AIQ), which is based on the empirically supported Cattell-Horn-Carroll (CHC) Theory of Intelligence. The predictive validity of the AIQ was determined in relation to performance metrics from 146 NFL players across several seasons.
Hierarchical regression analyses indicate that specific AIQ factors accounted for a statistically significant increase in the explanation of variance beyond the current level of evaluation for several performance metrics (e.g., career approximate value; sacks, tackles, rushing yards). Further, specific factors of the AIQ are related to position specific statistics, offering the possibility that performance prediction can be focused in for the specific skills required by a given position.
Given the recent impact of analytics in professional sports, and the significant findings noted in the current investigation, the authors discuss the potential importance of the AIQ in the selection and coaching processes.
The 2008 Physical Activity Guidelines recommend that the more than 53 million people living with a physical disability in the United States to participate in regular physical activities consisting of both aerobic and anaerobic components, if possible. Also, if individuals with physical disabilities are unable to meet the recommended physical activity guidelines, they are encouraged to do as much as their physical disability permits. Despite the recommended guidelines, several individuals with physical disabilities do not participate in regular physical activities. Prior research suggests that several societal and structural barriers in sport and exercise environments often negatively affect individuals with physical disabilities. Thus, it is essential for family members, healthcare practitioners, rehabilitation/recreational teams, and community leaders to encourage individuals with physical disabilities to conquer barriers that restrict participation.
Professor Faculty of Education-Physical and Health EducationDepartment of Teacher Training Shizuoka University Japan
Lecturer School of Sport and Exercise Massey UniversityPrivate Bag 11-222 Palmerston North 4474 New Zealand
Associate Professor National Institute of EducationNanyang Technological University 50 Nanyang Ave 639798, Singapore
Assistant ProfessorSport and Exercise Medicine UnitDepartment of Clinical and Experimental Medicine University of Florence Firenze 50121, Italy
Professor of Medicine Adjunct Professor of Sports Medicine and NutritionUniversity of Pittsburgh Chief of Sports MedicineDirector of Non Invasive Cardiac LaboratoryUniversità degli Studi di Firenze Azienda Ospedaliera Universitaria CareggiFirenze 50121, Italy