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Background Ageing is associated with decreased physical activity, obesity and subsequently an increased risk of developing type 2 diabetes mellitus (T2dm). Master athletes (MA) have initiated exercise or sport later in life or pursued a physically active lifestyle for an extended period. Subsequently, MAs have been proposed as a model of successful ageing as this active lifestyle is associated with health benefits including decreased health risk of chronic diseases and a reduction in premature mortality. Given long-term physical activity/exercise has previously been shown to be protective against hyperglycemia, a risk factor for T2dm, it is plausible that MA may have protective benefit against developing hyperglycemia. Therefore, the aim of this study was to investigate the prevalence of hyperglycemia via fasting plasma glucose (FPG) in MAs competing at the World Masters Games (WMG). Methods This cross-sectional, observational survey utilized an online survey using open-source web-based software was used to investigate MAs physiological and medical-related parameters. Over 28,000 MAs competed in the WMG, of which 8,072 MAs completed the survey. Of these MAs, a total of 486 (males 277, females 209; range 27 to 91 years, mean age 55.1 ± 10.2 years) attained recent pathology results which included FPG which was subsequently analyzed for this study. FPG and other outcome variables were compared between genders and to the Australian and United States general population. Results Mean FPG for MAs was 5.03 mmol (±1.2, 95% CI [4.9–5.1] mmol) with majority (75.5%) of MAs reporting a normal (5.51 to 7.0 mmol). There was no significant difference (P = 0.333) in FPG between genders however, males had a slightly higher (+2.1%) FPG as compared to females (5.08 ± 1.2 mmol (95% CI [4.9–5.22] mmol) versus 4.98 ± 1.1 mmol (95% CI 4.8-5.1 mmol)). The majority of males (71.8%) and females (80.3%) were classified with a normal FPG. With regard to an abnormal FPG level, only 4.0% of males and 4.9% of females were classified abnormal which was suggestive of undiagnosed T2dm. With regard to age by decade, there was no significant difference (P = 0.06–1.00) between age groups and no relationship between the MAs’ age and FPG (r = .054, P = 0.24). As a group, MAs had a significantly lower FPG as compared to the Australian (−3.2%, P = 0.005) and United States general populations (−13.9%, P < 0.001). Conclusions Most, however not all, MAs were found to have normal glycaemia, with only a small percentage indicating a risk of developing T2dm (i.e., impaired fasting glucose) and a smaller percentage identified with an abnormal FPG, suggestive of T2dm. These findings suggest MAs appear to be at low metabolic risk for developing T2dm based upon FPG and the physical activity/exercise they complete as MAs may indeed be protective against hyperglycemia whilst maintaining an active lifestyle.

Understanding the nexus between aging, physical activity, and obesity has been a source of ongoing investigation. A considerable amount of research has focused on Masters athletes in this regard, suggesting a beneficial relationship between Masters sport participation and a healthy body mass index (BMI). Some consider Active Duty military personnel as tactical athletes. As such, it is of interest to determine if aging Active Duty military personnel (or Masters Tactical Athletes) might have a similar BMI as other Masters athletes (MA). As such, this investigation examined previously recorded data of Active Duty Enlisted United States Marines (n = 402, male, 46–50 years old). The BMI of the Marines was stratified into categories of: underweight, normal, overweight, and obese. The Marines obesity prevalence was compared to US adult males (40–59 years) as well as male North American MA who competed at the 2009 Sydney World Masters Games. The Marines obesity prevalence was significantly lower than US adult males (p < 0.001) and those MA that competed in softball (p < 0.001); however, it was similar to MA that competed in football, track/field, swimming, and volleyball (p > 0.05). The average Marine BMI = 26.7 kg/m2 was similar to MA who competed in football, swimming, and volley ball (p > 0.05); however, it was higher than MA who competed in track/field (p < 0.05) and lower than MA who played softball (p < 0.05). It should be noted that the average BMI for the Marines and all MA sport categories were classified as being overweight. Within the parameters of this investigation, Tactical MA (i.e., aging US Marines) enjoy a similar beneficial BMI as other North American MA.

A predictable aggregation of dwarf minke whales occurs annually in the Australian offshore waters of the northern Great Barrier Reef in June–July, which has been the subject of a long-term photo-identification study. Researchers from the Minke Whale Project (MWP) at James Cook University collect large volumes of underwater digital imagery each season (e.g. 1.8TB in 2018), much of which is contributed by citizen scientists. Manual processing and analysis of this quantity of data had become infeasible, and Convolutional Neural Networks (CNNs) offered a potential solution. Our study sought to design and train a CNN that could detect whales from video footage in complex near-surface underwater surroundings containing multiple people, boats, research and recreational gear. We modified known classification CNNs to localize whales in video frames and digital still images. The required high detection accuracy was achieved by discovering an effective negative-labeling training technique. This resulted in a less than 1% false-positive detection rate and below 0.1% false-negative rate. The final operation-version CNN-pipeline processed all videos (with the interval of 10 frames) in approximately four days (running on two GPUs) delivering 1.95 million sorted images.

Xenotransplantation research has made considerable progress in recent years, largely through the increasing availability of pigs with multiple genetic modifications, effective immunosuppressive therapy, and anti-inflammatory therapy to protect pig tissues from the primate immune and inflammatory responses and correct molecular incompatibilities. Further study is required regarding identification and investigation of physiological incompatibilities. Although the exact cause remains uncertain, we and others have observed relatively rapid growth of kidney xenografts after transplantation into nonhuman primates (NHPs). There has also been some evidence of growth, or at least ventricular hypertrophy, of the pig heart after orthotopic transplantation into NHPs. Rapid growth could be problematic, particularly with regard to the heart within the relatively restricted confines of the chest. It has been suggested that the problem of rapid growth of the pig organ after transplantation could be resolved by growth hormone receptor (GHR) gene knockout in the pig. The GHR, although most well-known for regulating growth, has many other biological functions, including regulating metabolism and controlling physiological processes. Genetically modified GHRKO pigs have recently become available. We provide data on their growth compared to comparable pigs that do not include GHRKO, and we have reviewed the literature regarding the effect of GHRKO, and its relevance to xenotransplantation.

The critical shortage of human organs for allotransplantation has led to intensive research on xenotransplantation, with the pig being the species of choice as an organ source. However, wild-type pig organs undergo rapid hyperacute rejection (HAR) when transplanted into non-human primates (NHP), due the existence of preformed anti-pig antibodies expressed in the recipient. In NHP, these antibodies are directed to galactose-α1,3-galactose (Gal) and SDa. Humans express antibodies to both of these antigens, but also to N-glycolylneuraminic acid (Neu5Gc), and are thus anticipated to elicit a similar response. Hyperacute rejection stems from the binding of preformed antibodies to xenoantigens on the pig vascular endothelium, followed by complement-mediated endothelial lysis, interstitial hemorrhage, and necrosis.

Crossfit participation has experienced exponential growth. Like other sports, it may be that successful participation in Crossfit would rely upon a construct known as grit. Grit is considered to be a combination of perseverance of effort (PE) and consistency of interest (CI) and has been assessed in other populations with the 12-point Grit Scale. The ability to reliably assess grit among Crossfit participants may allow participants and coaches to monitor the constructs of PE and CI in order to further develop Crossfit participation skills. Hence, the purpose of this study was to examine the reliability of the 12-point Grit Scale among adult Crossfit participants. The 12-point Grit Scale was electronically administered twice to 25 adult Crossfit participants (female:11, male:14) separated by at least two weeks. The results of the two administrations of the 12-point Grit Scale were then compared with a battery of statistical analyses in order to assess the reliability of the 12-point Grit Scale. The test-retest 12-point Grit Scale scores were: 49.8±5.3 and 50.2±5.4. The reliability statistics along with 90% confidence limits were as follows: interclass reliability coefficient was r=0.87 (UL:0.94, LL:0.73), intraclass reliability coefficient was ICC=0.91 (UL:0.96, LL:0.83), Standard Error of Measurement (SEm)=1.6 (UL:2.2, LL:1.3), ∆Means 12-point Grit Scores= -0.3±2.3 (UL:0.6, LL:-1.2), and typical error CV% =3.4 (UL:4.8, LL:2.7). The Bland-Altman plot suggested agreement between the two administrations of the 12-point Grit Scale with no evidence of heteroscedasticity. The results of the 12-point Grit Scale and subscales ranged from moderately-high to excellent reliability among adult Crossfit participants.

In order to stimulate further adaptation toward a specific training goal(s), progression in the type of resistance training protocol used is necessary. The optimal characteristics of strength-specific programs include the use of both concentric and eccentric muscle actions and the performance of both single- and multiple-joint exercises. It is also recommended that the strength program sequence exercises to optimize the quality of the exercise intensity (large before small muscle group exercises, multiple-joint exercises before single-joint exercises, and higher intensity before lower intensity exercises). For initial resistances, it is recommended that loads corresponding to 8-12 repetition maximum (RM) be used in novice training. For intermediate to advanced training, it is recommended that individuals use a wider loading range, from 1-12 RM in a periodized fashion, with eventual emphasis on heavy loading (1-6 RM) using at least 3-min rest periods between sets performed at a moderate contraction velocity (1-2 s concentric, 1-2 s eccentric). When training at a specific RM load, it is recommended that 2-10% increase in load be applied when the individual can perform the current workload for one to two repetitions over the desired number. The recommendation for training frequency is 2-3 d x wk(-1) for novice and intermediate training and 4-5 d x wk(-1) for advanced training. Similar program designs are recommended for hypertrophy training with respect to exercise selection and frequency. For loading, it is recommended that loads corresponding to 1-12 RM be used in periodized fashion, with emphasis on the 6-12 RM zone using 1- to 2-min rest periods between sets at a moderate velocity. Higher volume, multiple-set programs are recommended for maximizing hypertrophy. Progression in power training entails two general loading strategies: 1) strength training, and 2) use of light loads (30-60% of 1 RM) performed at a fast contraction velocity with 2-3 min of rest between sets for multiple sets per exercise. It is also recommended that emphasis be placed on multiple-joint exercises, especially those involving the total body. For local muscular endurance training, it is recommended that light to moderate loads (40-60% of 1 RM) be performed for high repetitions (15) using short rest periods (90 s). In the interpretation of this position stand, as with prior ones, the recommendations should be viewed in context of the individual's target goals, physical capacity, and training status.