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The human pathogen Pseudomonas aeruginosa ( Pa ) poses a major risk for a range of severe infections, particularly lung infections in patients suffering from cystic fibrosis (CF). As previously reported, the virulent behavior of this pathogen is enhanced by elevated levels of Ca 2+ that are commonly present in CF nasal and lung fluids. In addition, a Ca 2+ -binding EF-hand protein, EfhP (PA4107), was partially characterized and shown to be critical for the Ca 2+ -regulated virulence in P. aeruginosa . Here, we describe the rapid (10 min, 60 min), and adaptive (12 h) transcriptional responses of PAO1 to elevated Ca 2+ detected by genome-wide RNA sequencing and show that efhP deletion significantly hindered both rapid and adaptive Ca 2+ regulation. The most differentially regulated genes included multiple Fe sequestering mechanisms, a large number of extracytoplasmic function sigma factors (ECFσ), and several virulence factors, such as the production of pyocins. The Ca 2+ regulation of Fe uptake was also observed in CF clinical isolates and appeared to involve the global regulator Fur. In addition, we showed that the efhP transcription is controlled by Ca 2+ and Fe, and this regulation required a Ca 2+ -dependent two-component regulatory system CarSR. Furthermore, the efhP expression is significantly increased in CF clinical isolates and upon pathogen internalization into epithelial cells. Overall, the results established for the first time that Ca 2+ controls Fe sequestering mechanisms in P. aeruginosa and that EfhP plays a key role in the regulatory interconnectedness between Ca 2+ and Fe signaling pathways, the two distinct and important signaling pathways that guide the pathogen's adaptation to the host.IMPORTANCE Pseudomonas aeruginosa ( Pa ) poses a major risk for severe infections, particularly in patients suffering from cystic fibrosis (CF). For the first time, kinetic RNA sequencing analysis identified Pa rapid and adaptive transcriptional responses to Ca 2+ levels consistent with those present in CF respiratory fluids. The most highly upregulated processes include iron sequestering, iron starvation sigma factors, and self-lysis factors pyocins. An EF-hand Ca 2+ sensor, EfhP, is required for at least 1/3 of the Ca 2+ response, including the majority of the iron uptake mechanisms and the production of pyocins. Transcription of efhP itself is regulated by Ca 2+ and Fe, and increases during interactions with host epithelial cells, suggesting the protein's important role in Pa infections. The findings establish the regulatory interconnectedness between Ca 2+ and iron signaling pathways that shape Pa transcriptional responses. Therefore, understanding Pa's transcriptional response to Ca 2+ and associated regulatory mechanisms will serve in the development of future therapeutics targeting Pa 's dangerous infections., Competing Interests: The authors declare no conflict of interest.

Background/Objectives: Previous evidence has shown that American football headgear (e.g., facemasks, visors/eye shields) differentially impairs reaction time (RT) to visual stimuli, most notably in peripheral fields of view. However, this has only been established with stationary RT testing, which may not translate to gameplay situations that require gross motor skills. Therefore, the purpose of this study was to build upon previous findings to elucidate the effects of various American football headgear on gross motor visuomotor drill performance. Methods: Division 1 NCAA football players (n = 16) with normal/corrected-to-normal vision participated and completed two experiments (EXP), each with differing conditions: EXP1- Varying facemask reinforcement and EXP2- Varying visor/eye shield light transmittance. In EXP1, participants completed an agility test for the following conditions: baseline/no helmet (BL), helmet + light (HL), helmet + medium (HM), and helmet + heavy (HH) face mask reinforcement. In EXP2, participants completed an agility test for the following conditions: baseline/no helmet (BL), helmet + clear visor (HCV), helmet + smoke-tinted visor (HSV), and helmet + mirrored visor (HMV). For each condition in EXP1 and EXP2, participants completed a reactive agility task using a FITLIGHT trainer system where five poles were equipped with a total of ten LED sensors and were placed in a semi-circle 1 m around a center point. Participants were asked to step and reach with their hands to hit each ten lights individually as fast as possible upon illumination. Each reactive agility test was repeated for a total of three attempts. Results: Average reaction time was analyzed and compared between conditions and according to visual fields of interest (e.g., central vs. peripheral). Results from EXP1 showed that compared to BL, reactive agility was worsened by HL ( p = 0.030), HM ( p = 0.034), and HH ( p = 0.003) conditions. No differences between facemask conditions existed for overall performance ( p > 0.05). For EXP2, HCV ( p < 0.001), HSV ( p < 0.001), and HMV ( p < 0.001) conditions resulted in worsened reactive agility performance compared to BL. No differences between visor conditions existed for overall performance ( p > 0.05). Conclusions: Overall, these findings suggest that American football headgear impairs reactive agility, which could result in worsened game performance and safety. Future studies investigating training strategies to overcome impairments are warranted.

The cystic fibrosis (CF) lung environment is conducive to the colonization of bacteria as polymicrobial biofilms, which are associated with poor clinical outcomes for persons with CF (pwCF). Streptococcus spp. are highly prevalent in the CF airway, but its role in the CF lung microbiome is poorly understood. Some studies have shown Streptococcus spp. to be associated with better clinical outcomes for pwCF, while others show that high abundance of Streptococcus spp. is correlated with exacerbations. Our lab previously reported a polymicrobial culture system consisting of four CF-relevant pathogens that can be used to study microbial behavior in a more clinically relevant setting. Here, we use this model system to identify genetic pathways that are important for Streptococcus sanguinis survival in the context of the polymicrobial community. We identified genes related to reactive oxygen species as differentially expressed in S. sanguinis monoculture versus growth of this microbe in the mixed community. Genetic studies identified Dpr as important for S. sanguinis survival in the community. We show that Dpr, a DNA-binding ferritin-like protein, and PerR, a peroxide-responsive transcriptional regulator of Dpr, are important for protecting S. sanguinis from phenazine-mediated toxicity in co-culture with Pseudomonas aeruginosa and when exposed to hydrogen peroxide, both of which mimic the CF lung environment. Characterizing such interactions in a clinically relevant model system contributes to our understanding of microbial behavior in the context of polymicrobial biofilm infections., Importance: Streptococcus spp. are recognized as a highly prevalent pathogen in cystic fibrosis (CF) airway infections. However, the role of this microbe in clinical outcomes for persons with CF is poorly understood. Here, we leverage a polymicrobial community system previously developed by our group to model CF airway infections as a tool to investigate a Pseudomonas - Streptococcus interaction involving reactive oxygen species (ROS). We show that protection against ROS is required for Streptococcus sanguinis survival in a clinically relevant polymicrobial system. Using this model system to study interspecies interactions contributes to our broader understanding of the complex role of Streptococcus spp. in the CF lung., Competing Interests: The authors declare no conflict of interest.

Dinosauria debuted on Earth's stage in the aftermath of the Permo-Triassic Mass Extinction Event, and survived two other Triassic extinction intervals to eventually dominate terrestrial ecosystems. More than 231 million years ago, in the Upper Triassic Ischigualasto Formation of west-central Argentina, dinosaurs were just getting warmed up. At this time, dinosaurs represented a minor fraction of ecosystem diversity. Members of other tetrapod clades, including synapsids and pseudosuchians, shared convergently evolved features related to locomotion, feeding, respiration, and metabolism and could have risen to later dominance. However, it was Dinosauria that radiated in the later Mesozoic most significantly in terms of body size, diversity, and global distribution. Elevated growth rates are one of the adaptations that set later Mesozoic dinosaurs apart, particularly from their contemporary crocodilian and mammalian compatriots. When did the elevated growth rates of dinosaurs first evolve? How did the growth strategies of the earliest known dinosaurs compare with those of other tetrapods in their ecosystems? We studied femoral bone histology of an array of early dinosaurs alongside that of non-dinosaurian contemporaries from the Ischigualasto Formation in order to test whether the oldest known dinosaurs exhibited novel growth strategies. Our results indicate that the Ischigualasto vertebrate fauna collectively exhibits relatively high growth rates. Dinosaurs are among the fastest growing taxa in the sample, but they occupied this niche alongside crocodylomorphs, archosauriformes, and large-bodied pseudosuchians. Interestingly, these dinosaurs grew at least as quickly, but more continuously than sauropodomorph and theropod dinosaurs of the later Mesozoic. These data suggest that, while elevated growth rates were ancestral for Dinosauria and likely played a significant role in dinosaurs' ascent within Mesozoic ecosystems, they did not set them apart from their contemporaries., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Curry Rogers et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Purpose: Ammonia inhalants (NH 3 ) are anecdotally used in competition by athletes for their purported stimulant effects. However, evidence on the efficacy of NH 3 is conflicting, and little to no studies to date have investigated its effect on repeated exercise. The purpose of this study was to examine the effects of NH 3 on psychophysiological responses and performance during repeated high-intensity exercise. Methods: In a counterbalanced crossover design, physically active females completed two repeated high-intensity sprint trials with a different treatment: Control (CON; water) or Ammonia Inhalants (NH 3 ; 0.33 cc). For each trial, participants completed 3 × 15s Wingate anaerobic tests (WAnT) separated by 2 min of active recovery. Prior to each WAnT, participants took a single 3-s inhale of the corresponding treatment. After the succession of each WAnT, heart rate (HR) and rate of perceived exertion (RPE) were documented. Subjective feelings of alertness and "psyched up" energy were measured using a visual analog scale. Trials were separated by at least 48 hr. Results: The results indicate that over the WAnTs, mean power (p = .017) and peak power (p = .006) were significantly higher with NH 3 compared to CON despite a lack of changes in fatigue index (p = .928). HR (p = .101) and RPE (p = .897) were not different with varying treatments. Perceived alertness (p = .010) and psyched-up energy (p = .002) were significantly higher with NH 3 versus CON. Conclusion: These findings provide empirical support for the use of NH 3 to improve repeated high-intensity exercise performance in females that may be underpinned by alterations in subjective alertness and energy.

Bacterial infections in the lungs of persons with cystic fibrosis are typically composed of multispecies biofilm-like communities, which modulate clinically relevant phenotypes that cannot be explained in the context of a single species culture. Most analyses to date provide a picture of the transcriptional responses of individual pathogens; however, there is relatively little data describing the transcriptional landscape of clinically relevant multispecies communities. Harnessing a previously described cystic fibrosis-relevant, polymicrobial community model consisting of Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus sanguinis, and Prevotella melaninogenica , we performed an RNA-Seq analysis on the biofilm population to elucidate the transcriptional profiles of the community grown in artificial sputum medium (ASM) as compared to growth in monoculture, without mucin, and in fresh medium supplemented with tobramycin. We provide evidence that, although the transcriptional profile of P. aeruginosa is community agnostic, the transcriptomes of S. aureus and S. sanguinis are community aware. Furthermore, P. aeruginosa and P. melaninogenica are transcriptionally sensitive to the presence of mucin in ASM, whereas S. aureus and S. sanguinis largely do not alter their transcriptional profiles in the presence of mucin when grown in a community. Only P. aeruginosa shows a robust response to tobramycin. Genetic studies of mutants altered in community-specific growth provide complementary data regarding how these microbes adapt to a community context. IMPORTANCE Polymicrobial infections constitute the majority of infections in the cystic fibrosis (CF) airway, but their study has largely been neglected in a laboratory setting. Our lab previously reported a polymicrobial community that can help explain clinical outcomes in the lungs of persons with CF. Here, we obtained transcriptional profiles of the community versus monocultures to provide transcriptional information about how this model community responds to CF-related growth conditions and perturbations. Genetic studies provide complementary functional outputs to assess how the microbes adapt to life in a community.

In gene therapy, potential integration of therapeutic transgene into host cell genomes is a serious risk that can lead to insertional mutagenesis and tumorigenesis. Viral vectors are often used as the gene delivery vehicle, but they are prone to undergoing integration events. More recently, non-viral delivery of linear DNAs having modified geometry such as closed-end linear duplex DNA (CELiD) have shown promise as an alternative, due to prolonged transgene expression and less cytotoxicity. However, whether modified-end linear DNAs can also provide a safe, non-integrating gene transfer remains unanswered. Herein, we compare the genomic integration frequency upon transfection of cells with expression vectors in the forms of circular plasmid, unmodified linear DNA, CELiDs with thioester loops, and Streptavidin-conjugated blocked-end linear DNA. All of the forms of linear DNA resulted in a high fraction of the cells being stably transfected-between 10 and 20% of the initially transfected cells. These results indicate that blocking the ends of linear DNA is insufficient to prevent integration., (© 2023. The Author(s).)

Previous studies have shown that listening to preferred music during resistance and endurance exercises improves performance. However, it is unknown if these phenomena translate to short-duration explosive exercises. The purpose of this study was to investigate the influences of preferred and non-preferred music on countermovement jump (CMJ) performance, isometric mid-thigh pull (IMTP), and psychological responses to music during explosive movements. Physically active females (age 18-25) volunteered to take part in the study. In a counterbalanced, crossover design, participants completed three trials: (1) no music (NM), (2) non-preferred (NP), and (3) preferred (PV) music. Participants completed three maximal IMTP tests on a force-plate-equipped IMTP apparatus with an immovable bar. Attempts lasted 5 s and were separated by 3 min of rest. Furthermore, participants completed three single maximal CMJ attempts separated by 3 min of rest on force plates. All attempts were averaged for analysis. At the commencement of IMTP and CMJ testing, participants were asked to rate how motivated and psyched up they felt during the exercise portion using a visual analog scale. For isometric performance, listening to PM resulted in increased peak force ( p = 0.039; d = 0.41) and rate of force development at 200 ms ( p = 0.023; d = 0.91) compared with NP. For CMJ, there were no differences between conditions for jump height ( p = 0.912; η 2 = 0.007) or peak power during the propulsive phase ( p = 0.460; η 2 = 0.003). Levels of motivation were significantly higher with PM compared with NM ( p < 0.001; d = 2.3) and NP ( p = 0.001; d = 2.0). Feelings of being psyched up were significantly higher with PM compared with NM ( p < 0.001; d = 4.2) and NP ( p = 0.001; d = 2.8). Findings suggest that preferred music enhances isometric strength and increases motivation and feelings of being psyched up. Thus, PM may be used as an ergogenic aid during short-duration maximal-effort activities.

Various tastes including sweet, bitter, and sour have been shown to differentially influence physiological and psychological processes. Furthermore, ingestion of bitter and sweet solutions has been shown to acutely enhance exercise performance. However, the taste is highly individualized, and it is unclear if preference influences the ergogenic potential of taste. The purpose of this study was to investigate the effects of preferred and non-preferred drink tastes on anaerobic performance and psychological responses thereof. Physically active females participated in two counterbalanced sprint trials each with a different condition: (1) non-preferred taste (NPT), (2) Preferred taste (PT). Participants self-reported taste preferences (sweet, sour, bitter) with the highest-ranked taste being used for the PT condition and the lowest-ranked for NPT. For each visit, participants completed a 15 s Wingate Anaerobic Test (WAnT) prior to (PRE) ingestion of ~20 mL of their NP or PREF taste. Following ingestion, participants completed 2 min of active recovery, rated their taste preference of the solution, and completed another 15 s WAnT. The rate of perceived exertion (RPE), motivation, and enjoyment were measured through a visual analog scale following each WAnT. Anaerobic performance measures and heart rate (HR) were also obtained at the succession of each WAnT. Findings revealed no differences between taste conditions for mean power ( p = 0.455), peak power ( p = 0.824), or HR ( p = 0.847). RPE was significantly lower with PT versus NPT ( p = 0.006). Exercise enjoyment ( p = 0.022) was higher with PT compared to NPT. NPT resulted in worse motivation compared to PRE ( p = 0.001) while no changes were observed between PT and PRE ( p = 0.197). These findings suggest that preferred drink taste may not enhance acute performance but improves psychological responses to maximal anaerobic exercise which may have implications for improving exercise training and adherence.

Fluid availability may alter drinking behavior; however, it is currently unknown if the availability of fluid impacts behavior and gastrointestinal issues (GI) that are often associated with increased fluid intake. The purpose of this study was to determine if ad libitum (AL) versus periodic (PER) fluid intake influences fluid consumption and GI distress during exercise in trained athletes. Male and female Division I NCAA Cross Country athletes (n = 11; age = 20 ± 1 years) participated in this counterbalanced crossover study. Each participant completed a moderate intensity 10 km run on two separate occasions. In one trial, participants had unlimited availability to fluid to consume AL. In the other trial, participants consumed PER fluid at stations placed every 3.2 km. Assurance of euhydration prior to each trial was confirmed via urine specific gravity (USG) and urine color. Subjective perceptions of thirst and gastric fullness were assessed pre- and post-exercise via Likert questioning and a visual analog scale, respectively. Participants started each trial euhydrated (AL = 1.009 USG ± 0.009; PER = 1.009 USG ± 0.009; urine color AL, 3 ± 1; urine color PER, 2 ± 1). Fluid volume consumption was significantly higher during the AL condition compared to PER (p = 0.050). Thirst significantly increased from pre- to post-run regardless of treatment (p < 0.001); however, there was no significant difference between the groups (p = 0.492). Feelings of fullness did not change pre-post trial (p = 0.304) or between trials (p = 0.958). Increased fluid availability allows for increased fluid consumption without the negative experience of GI discomfort.

The Journal of Human Evolution (JHE) was founded 50 years ago when much of the foundation for how we think about human evolution was in place or being put in place, providing the main framework for how we consider our origins today. Here, we will explore historical developments, including early JHE outputs, as they relate to our understanding of the relationship between phenotypic variation and evolutionary process, and use that as a springboard for considering our current understanding of these links as applied to human evolution. We will focus specifically on how the study of variation itself has shifted us away from taxonomic and adaptationist perspectives toward a richer understanding of the processes shaping human evolutionary history, using literature searches and specific test cases to highlight this. We argue that natural selection, gene exchange, genetic drift, and mutation should not be considered individually when considering the production of hominin diversity. In this context, we offer suggestions for future research directions and reflect on this more complex understanding of human evolution and its broader relevance to society. Finally, we end by considering authorship demographics and practices in the last 50 years within JHE and how a shift in these demographics has the potential to reshape the science of human evolution going forward., Competing Interests: Declaration of competing interest The authors have no conflicts of interest to declare., (Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

The spectacular fossil fauna and flora preserved in the Upper Cretaceous terrestrial strata of North America's Western Interior Basin record an exceptional peak in the diversification of fossil vertebrates in the Campanian, which has been termed the 'zenith of dinosaur diversity'. The wide latitudinal distribution of rocks and fossils that represent this episode, spanning from northern Mexico to the northern slopes of Alaska, provides a unique opportunity to gain insights into dinosaur paleoecology and to address outstanding questions regarding faunal provinciality in connection to paleogeography and climate. Whereas reliable basin-wide correlations are fundamental to investigations of this sort, three decades of radioisotope geochronology of various vintages and limited compatibility has complicated correlation of distant fossil-bearing successions and given rise to contradictory paleobiogeographic and evolutionary hypotheses. Here we present new U-Pb geochronology by the CA-ID-TIMS method for 16 stratigraphically well constrained bentonite beds, ranging in age from 82.419 ± 0.074 Ma to 73.496 ± 0.039 Ma (2σ internal uncertainties), and the resulting Bayesian age models for six key fossil-bearing formations over a 1600 km latitudinal distance from northwest New Mexico, USA to southern Alberta, Canada. Our high-resolution chronostratigraphic framework for the upper Campanian of the Western Interior Basin reveals that despite their contrasting depositional settings and basin evolution histories, significant age overlap exists between the main fossil-bearing intervals of the Kaiparowits Formation (southern Utah), Judith River Formation (central Montana), Two Medicine Formation (western Montana) and Dinosaur Park Formation (southern Alberta). Pending more extensive paleontologic collecting that would allow more rigorous faunal analyses, our results support a first-order connection between paleoecologic and fossil diversities and help overcome the chronostratigraphic ambiguities that have impeded the testing of proposed models of latitudinal provinciality of dinosaur taxa during the Campanian., (© 2022. The Author(s).)

Afro-Eurasian monkeys originated in the Miocene and are the most species-rich modern primate family. Molecular and fossil data have provided considerable insight into their evolutionary divergence, but we know considerably less about the evolutionary processes that underlie these differences. Here, we apply tests developed from quantitative genetics theory to a large (n > 3000) cranio-mandibular morphometric dataset, investigating the relative importance of adaptation (natural selection) and neutral processes (genetic drift) in shaping diversity at different taxonomic levels, an approach applied previously to monkeys of the Americas, apes, hominins, and other vertebrate taxa. Results indicate that natural selection, particularly for differences in size, plays a significant role in diversifying Afro-Eurasian monkeys as a whole. However, drift appears to better explain skull divergence within the subfamily Colobinae, and in particular the African colobine clade, likely due to habitat fragmentation. Small and declining population sizes make it likely that drift will continue in this taxon, with potentially dire implications for genetic diversity and future resilience in the face of environmental change. For the other taxa, many of whom also have decreasing populations and are threatened, understanding adaptive pressures similarly helps identify relative vulnerability and may assist with prioritising scarce conservation resources., (© 2022. The Author(s).)

Calcium (Ca 2+ ) is well known as a second messenger in eukaryotes, where Ca 2+ signaling controls life-sustaining cellular processes. Although bacteria produce the components required for Ca 2+ signaling, little is known about the mechanisms of bacterial Ca 2+ signaling. Previously, we have identified a putative Ca 2+ -binding protein EfhP (PA4107) with two canonical EF-hand motifs and reported that EfhP mediates Ca 2+ regulation of virulence factors production and infectivity in Pseudomonas aeruginosa, a human pathogen causing life-threatening infections. Here, we show that EfhP selectively binds Ca 2+ with 13.7 µM affinity, and that mutations at the +X and -Z positions within each or both EF-hand motifs abolished Ca 2+ binding. We also show that the hydrophobicity of EfhP increased in a Ca 2+ -dependent manner, however no such response was detected in the mutated proteins. 15  N-NMR showed Ca 2+ -dependent chemical shifts in EfhP confirming Ca 2+ -binding triggered structural rearrangements in the protein. Deletion of efhP impaired P. aeruginosa survival in macrophages and virulence in vivo. Disabling EfhP Ca 2+ binding abolished Ca 2+ induction of pyocyanin production in vitro. These data confirm that EfhP selectively binds Ca 2+ , which triggers its structural changes required for the Ca 2+ regulation of P. aeruginosa virulence, thus establishing the role of EfhP as a Ca 2+ sensor., (© 2022. The Author(s).)

The purpose of this study was to examine the effects of preferred versus non-preferred music volume on relative power output, trial time to completion (TTC), heart rate (HR), rate of perceived exertion (RPE), and motivation during endurance rowing exercise. Physically active females (age 18−25) volunteered to participate. In a crossover counterbalanced design, participants completed two trials: non-preferred (NPV) and preferred (PV) music volume. Participants began with a rowing warm-up at 50% of HRmax for 5 min. Following this, participants completed a 2000 m rowing time trial as quickly as possible. Relative power output, HR, and RPE were documented each minute during the exercise bout. TTC and motivation levels were documented at the cessation of exercise. Results showed that there were no significant differences between NPV and PV for relative power output (p = 0.287; d = 0.17), TTC (p = 0.816; d = 0.01), and HR (p = 0.956; d = 0.08). However, RPE was significantly lower (p = 0.002; d = 0.86) and motivation was significantly higher (p < 0.001; d = 2.14) during the PV condition versus NPV. Findings suggest that while PV does not impart performance-enhancing effects during endurance exercise compared to NPV, it may improve psychological responses related to intensity and effort which could have important implications for enduring intense exercise and training.

The purpose of this study was to examine the effects of a single acute dose of yohimbine hydrochloride on repeated anaerobic sprint ability. Physically active females ( n = 18) completed two separate repeated supramaximal sprint trials each with a different single-dose treatment: placebo (PL; gluten-free corn starch) or yohimbine hydrochloride (YHM; 2.5 mg). For each trial, participants consumed their respective treatment 20 min before exercise. Following a warm-up, participants completed 3 × 15 s Wingate anaerobic tests (WAnTs) separated by 2 min of active recovery. A capillary blood sample was obtained pre- and immediately post-exercise to measure blood concentrations of lactate (LA), epinephrine (EPI), and norepinephrine (NE). Heart rate (HR) and rate of perceived exertion (RPE) were measured following each WAnT. Findings showed that mean power ( p < 0.001; η 2 = 0.024), total work ( p < 0.001; η 2 = 0.061), and HR ( p < 0.001; η 2 = 0.046), were significantly higher with YHM supplementation versus PL. Fatigue index ( p < 0.001; η 2 = 0.054) and post-exercise LA ( p < 0.001; d = 1.26) were significantly lower with YHM compared to PL. YHM resulted in significantly higher EPI concentrations versus PL ( p < 0.001; η 2 = 0.225) pre- and post-exercise while NE only increased as a function of time ( p < 0.001; η 2 = 0.227) and was unaffected by treatment. While RPE increased after each WAnT, no differences between treatments were observed ( p = 0.539; η 2 < 0.001). Together, these results suggest that acute YHM ingestion imparts ergogenic benefits which may be mediated by lower blood LA and fatigue concomitantly occurring with blood EPI increases. Thus, YHM may improve sprint performance although more mechanistic study is warranted to accentuate underlying processes mediating performance enhancement.

The purpose of this study was to assess the effect of two fluid intake protocols on alertness and reaction time before and after fluid intake. Healthy college-age males ( n = 12) followed two fluid intake protocols on separate occasions: (1) prescribed fluid (PF) and fluid restricted (FR). In PF, participants were instructed to consume 500 mL of fluid the night prior to and the morning of data collection. In FR, participants were instructed to refrain from the consumption of fluid for 12 h. To assess hydration status, urine specific gravity and urine color were measured. Participants perceived level of thirst and alertness were also recorded. Participants then completed visuomotor reaction time tests using the Dynavision LED board, using both a central visuomotor test and a peripheral visuomotor test (PVRT) prior to (1) and following (2) the ingestion of 100 mL of water. Participants displayed significantly improved PVRT in PF state as compared to FR (PF1 = 1.13 ± 0.16, PF2 = 1.04 ± 0.14; FR1 = 1.27 ± 0.27, FR2 = 1.18 ± 0.20; p = 0.038, η p 2 = 0.363). Both CVRT and PVRT improved over time, following the ingestion of 100 mL of fluid. Participants in the PF state were also significantly more alert than participants in the FR state (PF = 4 ± 2, FR = 5 ± 2; p = 0.019, ES = 0.839). Collectively, perceived alertness and PVRT were negatively impacted by FR.

The purpose of this study was to investigate the effects of self-selected respite music on upper-body resistance exercise performance. In a crossover, counterbalanced study design, resistance-trained males ( n = 10) participated in two bench press trials each with a different condition: 1) No music (NM), 2) Listening to respite music (RM; i.e. during rest periods). Following a warm-up, participants completed 3 sets × repetitions to failure (RTF) at 75% of 1-RM separated by 2 minutes of rest. During the 2-minute rest, participants either listened to NM or RM until the next subsequent set. A linear position transducer was used to measure mean barbell velocity during the first 3 repetitions and averaged for analysis. Rate of perceived exertion (RPE) and motivation were obtained after each set. Results indicate that mean velocity was higher during set 2 ( p = 0.009; d = 1.34) and set 3 ( p = 0.048; d = 0.95) while listening to RM versus NM. Furthermore, motivation was significantly higher following set 2 ( p = 0.005; d = 1.15) and set 3 ( p < 0.001; d = 1.79) while listening to RM compared to NM. No changes in RTF or RPE were noted between conditions ( p > 0.05). These findings indicate listening to music during recovery may enhance subsequent explosive resistance performance and suggest that listening to music in between bouts of maximal effort could be an effective tool for optimizing performance during competition or training.

The increasing awareness that hybridization, and resultant gene flow, plays a major role in animal diversification has led to a growing number of studies that have focused on assessing the morphological consequences of this process. Analyses of mammalian hybrids have identified skeletal effects of hybridization, including a suite of anomalous dental and sutural traits on the skull that are present at high frequencies in hybrid populations. These studies have also detected consistent patterns of morphological shape and size differences between hybrids and parental taxa across a wide variety of organisms. However, more research is required to understand the universality of these traits and shape/size differences. Building on these previous studies, a sample of genetically determined canid hybrids was examined, specifically the eastern coyote (Canis latrans var.), a hybrid between coyotes, wolves, and dogs, to test whether this group exhibits a comparable pattern of anomalous nonmetric characters, and to assess differences in craniomandibular shape and size. First, specimens of C. latrans var., C. latrans, and C. lupus were scored for anomalous traits, including supernumerary and rotated teeth, dental crowding, and sutural anomalies. Geometric morphometric analyses were then conducted on a subset of these individuals to explore craniomandibular size and shape variation, as well as allometry. The results are largely consistent with other studies, indicating that the incidence of dental anomalies, dental crowding, and sutural anomalies is significantly higher in hybrids. However, differences are not significant for supernumerary teeth. The exploration of morphometric variation identifies intermediate morphology in the hybrids, and some indication of greater morphological variability in the mandible. When these results are combined with previous studies, they suggest that skeletal signatures of hybridization are common to different mammalian taxa across multiple generations; however, some traits such as supernumerary teeth may be lost after a few generations., (© 2021 Wiley Periodicals LLC.)

Ancient DNA analyses have shown that interbreeding between hominin taxa occurred multiple times. Although admixture is often reflected in skeletal phenotype, the relationship between the two remains poorly understood, hampering interpretation of the hominin fossil record. Direct study of this relationship is often impossible due to the paucity of hominin fossils and difficulties retrieving ancient genetic material. Here, we use a sample of known ancestry hybrids between two closely related nonhuman primate taxa (Indian and Chinese Macaca mulatta) to investigate the effect of admixture on skeletal morphology. We focus on pelvic shape, which has potential fitness implications in hybrids, as mismatches between maternal pelvic and fetal cranial morphology are often fatal to mother and offspring. As the pelvis is also one of the skeletal regions that differs most between Homo sapiens and Neanderthals, investigating the pelvic consequences of interbreeding could be informative regarding the viability of their hybrids. We find that the effect of admixture in M. mulatta is small and proportional to the relatively small morphological difference between the parent taxa. Sexual dimorphism appears to be the main determinant of pelvic shape in M. mulatta. The lack of difference in pelvic shape between Chinese and Indian M. mulatta is in contrast to that between Neanderthals and H. sapiens, despite a similar split time (in generations) between the hybridizing pairs. Greater phenotypic divergence between hominins may relate to adaptations to disparate environments but may also highlight how the unique degree of cultural buffering in hominins allowed for greater neutral divergence. In contrast to some previous work identifying extreme morphologies in first- and second-generation hybrids, here the relationship between pelvic shape and admixture is linear. This linearity may be because most sampled animals have a multigenerational admixture history or because of relatively high constraints on the pelvis compared with other skeletal regions., Competing Interests: Conflict of interest statement The authors declare no conflict of interest., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: Treadmill desks have been used extensively to increase physical activity and decrease sedentary time in the work environment. However, dual tasking, such as simultaneously walking and performing a cognitive task, may result in diminished performance in one or both tasks., Research Question: Do age and sex impact ability to dual task while using a treadmill desk at a preferred walking speed?., Methods: A total of n = 24 younger (range of 18-24 years, mean age = 21.1 ± 1.6 years) and n = 25 older (range of 45-65 years, mean age = 53.0 ± 5.1 years) adults self-selected a comfortable walking speed ranging from 0.5 to 2.0 mph and performed the Stroop Color & Word test (measuring Inhibition) and the Sternberg Test of Working Memory (measuring Working Memory) while walking at their chosen speed on a treadmill desk and while seated. Testing was performed in two separate sessions with the order counterbalanced. Step length, stride length, gait cycle time, and coefficient of variation (CV) for each were measured using OptoGait software, and both reaction time and accuracy for the two cognitive tests were assessed. Dual Task Cost (DTC) was calculated by using the formula (Single task score - Dual task score)/Single task score)*100., Results: Younger adults had faster reaction time compared to older adults for both Working Memory and Inhibition tests (p < 0.05), and both males and females had slower reaction time for the Working Memory test when seated compared to walking (p < 0.05). For DTC, older adults had greater stride length CV during the Working Memory task (32.0 % vs 19.6 %), and regardless of age or sex, DTC for gait was greater than for cognition., Significance: These data provide evidence that while aging does decrease reaction time while dual tasking, few age differences and no sex differences were found in dual task cost. However, dual tasking results in diminished gait DTC compared to cognition DTC regardless of age or sex., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Purpose: The purpose of this study was to investigate how time-of-day training preference influences resistance-exercise performance. Methods: Resistance trained males ( n = 12) were recruited for this study. In a crossover, counterbalanced design, participants completed two separate bench-press exercise trials at different times of day: (a) morning (AM; 8:00 hr) and (b) evening (PM; 16:00 hr). Participants answered a questionnaire on time-of-day training preference and completed a preferred (PREF) and nonpreferred (NON-PREF) time-of-day trial. For each trial, motivation was measured using a visual analog scale prior to exercise. Participants completed 2 sets × 2 repetitions at 75% 1-RM with maximum explosiveness separated by 5 min of rest. Mean barbell velocity was measured using a linear position transducer. Participants then completed 1 set × repetitions to failure (RTF) at 75% 1-RM. Rate of perceived exertion (RPE) was measured immediately following exercise. Results: Regardless of preference, velocity ( p = .025; effect size (ES) = 0.43) was higher during the PM versus AM trial. However, there were no significant differences in velocity ( p = .368; ES = 0.37) between PREF and NON-PREF time of day. There were no significant differences for repetitions between PREF and NON-PREF times ( p = .902; ES = 0.03). Motivation was higher in the PREF time versus NON-PREF ( p = .015; ES = 0.68). Furthermore, RPE was significantly lower during the PREF time of day ( p = .048; 0.55). Conclusions: Despite higher barbell velocity collectively at PM times, time-of-training preference did not largely influence resistance-exercise performance, while motivation is higher and RPE is lower during preferred times.

The purpose of this study was to investigate the effects of listening to preferred versus non-preferred warm-up music on anaerobic sprint performance in Division I NCAA female athletes. Female collegiate athletes ( n = 14) were recruited for this study. In a counterbalanced, crossover study design, participants completed two separate visits, each with a different warm-up music condition: preferred (Pref) or non-preferred (Non-pref). During each visit, participants completed a 3 min standardized cycling warm-up at 50 Watts while listening to Pref or Non-pref music. Following this, participants completed 3 × 15 s Wingate Anaerobic Tests (WAnTs) with a 2 min active recovery period in between tests. Motivation to exercise was measured immediately following the warm-up (WU), WAnT1, WAnT2, and WAnT3. The rate of perceived exertion (RPE) was also measured after each WAnT. Each visit was separated by a minimal recovery period of 48 h. Mean power, total work, RPE, and motivation were analyzed. Mean power ( p = 0.044; d = 0.91) and total work ( p = 0.045; d = 0.78) were significantly higher during the Pref music condition versus Non-pref. RPE remained unchanged regardless of condition ( p = 0.536; d = 0.01). Motivation was significantly higher with Pref warm-up music compared to Non-pref ( p < 0.001; d = 1.55). These results show that listening to Pref warm-up music has an ergogenic benefit during repeated sprints in comparison to Non-pref music and improves motivation to exercise. Listening to warm-up music prior to high-intensity repeated exercise may aid in optimizing performance and training in collegiate athletes.

Background: Many pregnant women report that their memory is impaired compared to non-pregnancy, but results of studies of cognitive abilities are mixed. The effect of pregnancy on dual tasking, or performance of two tasks simultaneously, has not been studied, however., Research Question: What is the effect of walking overground at a self-selected speed while also performing a cognitive task on gait and cognitive performance during 3rd trimester of pregnancy compared to non-pregnant controls?, Methods: A total of n = 22 3rd trimester pregnant women (mean 33.3 ± 3.3 weeks gestation, age 32.1 ± 4.7 years) and n = 21 non-pregnant controls (age 31.9 ± 3.3 years) were recruited to participate. All participants performed single task walking on a GAITRite gait analysis system and performed three cognitive tests while walking: serial 3 and 7 subtraction tests and a phoneme monitoring test. Participants completed the same assessments while seated and order of the testing was counterbalanced. Dual task cost (DTC) was calculated using the formula (Single task score - Dual task score)/Single task score)*100. Independent t-tests or Mann Whitney U tests were used to compare the two groups depending on normality of data., Results: There were no significant differences in cognitive test performance between control and pregnant women while walking or seated (p > 0.05). There were no significant differences between groups for DTC during any cognitive tests, but DTC was significantly greater for walking velocity in pregnant women compared to controls for serial 3 (p < 0.001) and serial 7 (p = 0.005) but not phoneme monitoring (p = 0.061)., Significance: Pregnant women had elevated cost of dual tasking, though the decrements were not in cognitive tests but in gait, specifically with greater DTC of walking velocity. This suggests that pregnant women modify their walking velocity to preserve cognitive function during activities requiring focus on both cognitive and physical tasks., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The purpose of this study was to examine the effects of short-term Golden Root Extract (GRE; Rhodiola rosea ) supplementation on blood lactate, catecholamines, and performance during repeated bench press exercise. Resistance-trained males ( n = 10) participated in this study. In a double-blinded, crossover, counterbalanced study design, participants supplemented with either 1500 mg/day of GRE or placebo (PL; gluten-free cornstarch) for 3 days prior to experimentation. An additional 500 mg dose was ingested 30 min prior to exercise testing. During each exercise trial, participants completed 2 repetitions of bench press at 75% of one-repetition maximum (1RM) as explosively as possible. A linear position transducer was used to measure mean concentric velocity. After 5 min of rest, participants completed 3 sets × repetitions to failure (RTF) at 75% 1RM separated by 2 min of rest between each set. A capillary blood sample was obtained pre- (PRE) and immediately post- (POST) exercise to measure blood concentrations lactate (LA), epinephrine (EPI), and norepinephrine (NE). Mean concentric velocity was significantly higher with GRE when compared to PL ( p = 0.046). However, total RTF were significantly lower with GRE versus PL ( p < 0.001). Regardless of treatment, LA was significantly higher Post versus Pre ( p < 0.001), but GRE resulted in greater Post values compared to PL ( p = 0.049). EPI and NE increased in both conditions Pre to Post ( p < 0.001). However, Pre NE was significantly higher with GRE versus PL ( p = 0.008). Findings indicate that short-term GRE supplementation increases mean bench press velocity but decreases bench press repetition volume. Furthermore, GRE resulted in higher NE levels and blood lactate following exercise. Thus, supplementing with GRE may enhance explosive resistance training performance but may also impair upper body strength-endurance.

The purpose of this study was to examine the effects of listening to pre-exercise music on bench press performance. We recruited 10 resistance trained males (M age= 22.8, SD = 5.8 years; M height= 173.7, SD = 8.3 cm; M body mass = 81.0, SD = 18.2 kg) for this crossover counterbalanced research design. Participants completed two bench press exercise trials of (a) No music (NM), and (b) Pre-exercise music (PreExM) separated by at least 48 hours. For each trial, following a warm-up, participants listened to music or no music for three minutes. After this 3-minute period, they completed one set of bench press repetitions with maximum explosive intent at 75% one repetition maximum (1 RPM). We used a rotary encoder to measure power and velocity of barbell movement. After a 3-minute rest during which they again listened to music or no music, participants completed another set of repetitions to failure (RTF) at 75% of 1RM. Immediately following this second set of repetitions, we measured exercise motivation with a visual analog scale (VAS). We found that the PreExM condition increased mean power output (p = 0.005; d = 0.792) and barbell velocity (p = 0.015; d = 0.722). RTF were significantly higher during the PreExM versus NM trial (p = 0.002; d = 0.985), and motivation was significantly higher in the PreExM trial versus NM (p = 0.001; d = 0.932). These findings suggest improved muscle power explosiveness and strength-endurance when listening to music before a bench press exercise. From a practical standpoint, athletes who have the option of listening to music immediately prior to resistance exercise may benefit from its use.

Abstract: Ballmann, CG, McCullum, MJ, Rogers, RR, Marshall, MR , and Williams, TD. Effects of preferred vs. nonpreferred music on resistance exercise performance. J Strength Cond Res 35(6): 1650-1655, 2021-The purpose of this study was to examine the effects of listening to preferred vs. nonpreferred music on resistance exercise performance. Twelve resistance-trained college-aged males (age = 20.5 ± 1.24 years, height = 183.9 ± 6.8 cm, and body mass = 97.0 ± 18.2 kg) were recruited for this study. In a within-groups counterbalanced study design, subjects either listened to preferred or nonpreferred music during a bench press exercise test. Subjects completed as many repetitions as possible at 75% of their 1 repetition maximum with maximum explosive intent. Power and velocity of the barbell movement was measured for the first 3 repetitions using a linear position transducer. Motivation was measured using a visual analog scale immediately after exercise. Each exercise trial was separated by a 48-hour washout period. Results indicate that listening to preferred music increased overall bench press repetitions completed (p = 0.005; effect size [ES] = 0.84). During the first 3 repetitions, mean velocity (p = 0.001; ES = 1.6), relative mean power (p = 0.012; ES = 0.55), peak velocity (p = 0.011; ES = 0.99), and peak power (p = 0.009; ES = 0.35) were higher while listening to preferred music vs. nonpreferred music. Finally, motivation during the lift (p < 0.001; ES = 5.9) was significantly higher while listening to preferred vs. nonpreferred music. Current findings suggest that listening to preferred music by the individual results in greater performance than nonpreferred during resistance exercise. Athletes may benefit from the option to listen to their preferred music to increase motivation and resistance exercise performance., (Copyright © 2019 National Strength and Conditioning Association.)

The purpose of this investigation was to determine the effects of varying facemask reinforcement and visor tint on peripheral visuomotor abilities in collegiate football players. Division I NCAA football players ( n = 14) completed two peripheral visuomotor experiments: (1) Varying facemask reinforcement, (2) Varying visor tinting. In experiment 1, participants were tested under the following conditions: baseline (no helmet; BL), helmet + light (HL), helmet + medium (HM), helmet + heavy (HH), and helmet + extra heavy (HXH) reinforced facemasks. In experiment 2, participants were tested under the following conditions: baseline (no helmet; BL), helmet only (HO), helmet + clear (HCV), helmet + smoke-tinted (HSV), and helmet + mirror-tinted (HMV) visors. For each condition, a 60 s peripheral visuomotor test was completed on a Dynavision D2 visuomotor board. For experiment 1, the BL peripheral reaction time (PRT) was faster than all facemask conditions ( p < 0.05). Furthermore, PRT was impaired with the HXH compared to HL ( p < 0.001), HM ( p < 0.001), and HH ( p = 0.001). Both HH and HXH resulted in the potentiation of PRT impairments in the outermost and inferior peripheral visual areas ( p < 0.05). In experiment 2, BL PRT was faster than all helmeted conditions ( p < 0.05). Additionally, PRT was slower in HSV ( p = 0.013) and HMV ( p < 0.001) conditions compared to HO. HMV resulted in slower PRT in all peripheral areas ( p < 0.05) while PRT was impaired only in outer areas for HSV ( p < 0.05). Wearing protective football headgear impairs peripheral visuomotor ability. Lighter reinforced facemasks and clear visors do not appear to exacerbate impairment. However, heavier reinforced facemasks and tinted visors further decrease visuomotor performance in outer and inferior visual areas, indicating a potential need for considerations of on-field player performance and safety.

The purpose of this study was to investigate the effects of how limb dominance and joint immobilization alter markers of physical demand and muscle activation during ambulation with axillary crutches. In a crossover, counterbalanced study design, physically active females completed ambulation trials with three conditions: (1) bipedal walking (BW), (2) axillary crutch ambulation with their dominant limb (DOM), and (3) axillary crutch ambulation with their nondominant limb (NDOM). During the axillary crutch ambulation conditions, the non-weight-bearing knee joint was immobilized at a 30-degree flexion angle with a postoperative knee stabilizer. For each trial/condition, participants ambulated at 0.6, 0.8, and 1.0 mph for five minutes at each speed. Heart rate (HR) and rate of perceived exertion (RPE) were monitored throughout. Surface electromyography (sEMG) was used to record muscle activation of the medial gastrocnemius (MG), soleus (SOL), and tibialis anterior (TA) unilaterally on the weight-bearing limb. Biceps brachii (BB) and triceps brachii (TB) sEMG were measured bilaterally. sEMG signals for each immobilization condition were normalized to corresponding values for BW.HR ( p < 0.001) and RPE ( p < 0.001) were significantly higher for both the DOM and NDOM conditions compared to BW but no differences existed between the DOM and NDOM conditions ( p > 0.05). No differences in lower limb muscle activation were noted for any muscles between the DOM and NDOM conditions ( p > 0.05). Regardless of condition, BB activation ipsilateral to the ambulating limb was significantly lower during 0.6 mph ( p = 0.005) and 0.8 mph ( p = 0.016) compared to the same speeds for BB on the contralateral side. Contralateral TB activation was significantly higher during 0.6 mph compared to 0.8 mph ( p = 0.009) and 1.0 mph ( p = 0.029) irrespective of condition. In conclusion, limb dominance appears to not alter lower limb muscle activation and walking intensity while using axillary crutches. However, upper limb muscle activation was asymmetrical during axillary crutch use and largely dependent on speed. These results suggest that functional asymmetry may exist in upper limbs but not lower limbs during assistive device supported ambulation.

The purpose of this study was to investigate physical and cognitive performance during dual task conditions of upper-extremity (UE) or full-body (FB) rowing exercise. In a crossover counterbalanced design, college-aged male and female participants completed five conditions: (a) Sitting, (b) Single task UE rowing, (c) Single task FB rowing, (d) Dual task UE rowing, and (e) Dual task FB rowing. For single task UE and FB rowing conditions, participants were asked to row as hard as possible. After sitting and dual-task conditions, we administered the Paced Auditory Serial Addition Test (PASAT) and a word-list memory test. We analyzed participants' absolute differences (single task - dual task) in power output and their cognitive test scores to compare UE and FB rowing. There were no significant absolute differences from sitting to dual task conditions of UE and FB rowing for either PASAT ( p  = 0.958) or word list memory ( p  = 0.899) cognitive scores. Absolute power output loss from single to dual task conditions was significantly higher in FB versus UE for PASAT ( p  = 0.039; d  = 0.54) and word list memory ( p  = 0.021; d  = 0.66) in the dual task condition. These results suggest that, while cognitive performance was preserved regardless of the amount of muscle mass activated during dual task rowing, physical performance suffered more during FB than UE rowing under the dual task condition. These findings have important implications for optimizing cognitive and physical performance in dual task situations.

Diurnal fluctuations in power output have been well established with power loss typically occurring in morning (AM) times. Beetroot juice (BRJ) is a source of dietary nitrate that possess ergogenic properties, but it is unknown if ingestion can mitigate performance decrements in the morning. The purpose of this study was to examine the effects of acute BRJ supplementation on diurnal fluctuations in anaerobic performance in trained sprinters. Male Division 1 National Collegiate Athletic Association (NCAA) sprinters ( n = 10) participated. In a double-blinded crossover study design, participants completed three counterbalanced exercise trials under different conditions: Morning-placebo (8:00 HR, AM-PL), Morning-BRJ (8:00 HR, AM-BRJ), and Afternoon-no supplement (15:00 HR, PM). For each trial, participants completed 3 × 15 s Wingate anaerobic tests separated by 2 min of rest. Each trial was separated by a 72 h washout period. Mean power output ( p = 0.043), anaerobic capacity ( p = 0.023), and total work ( p = 0.026) were significantly lower with the AM-PL condition compared to PM. However, BRJ supplementation prevented AM losses of mean power output ( p = 0.994), anaerobic capacity ( p = 0.941), and total work ( p = 0.933) in the AM-BRJ compared to the PM condition. Rate of perceived exertion was not significantly different between any conditions ( p = 0.516). Heart rate was significantly lower during the AM-BRJ condition compared to AM-PL ( p = 0.030) and PM ( p < 0.001). Findings suggest anaerobic capacity suffers during AM versus PM times in trained sprinters, but BRJ ingestion abolishes AM-associated decrements in performance.

The purpose of this study was to examine the effects of listening to preferred and non-preferred warm-up music on upper-body resistance exercise performance. Resistance-trained males (ages 18-24) participated in two separate bench press trials each with a different warm-up music condition: preferred warm-up music (PREF) or non-preferred warm-up music (NON-PREF). In each trial, participants listened to PREF or NON-PREF music during a standardized bench press warm-up. Following the warm-up, motivation to exercise was measured using a visual analog scale followed by two sets × repetitions to failure (RTF) at 75% of 1-RM separated by 1 min of rest. A linear position transducer was used to measure mean barbell velocity. Rate of perceived exertion (RPE) was obtained after each set. RTF, velocity, RPE, and motivation were analyzed. RTF were significantly higher during the PREF versus NON-PREF trail ( p = 0.001) while mean barbell velocity remained unchanged ( p = 0.777). RPE was not significantly different between PREF and NON-PREF trials ( p = 0.735). Motivation to exercise was significantly higher during the PREF versus NON-PREF trial ( p < 0.001). Findings show that listening to PREF music during a warm-up improves subsequent RTF performance during bench press exercise. However, barbell velocity was largely unaffected. While perceived exertion was similar between trials, motivation to exercise was markedly increased during the PREF warm-up music trial. These findings suggest that competitors listening to warm-up music before giving maximal effort during resistance exercise could optimize performance by ensuring self-selection of their own preferred music.

Mesozoic birds display considerable diversity in size, flight adaptations and feather organization 1-4 , but exhibit relatively conserved patterns of beak shape and development 5-7 . Although Neornithine (that is, crown group) birds also exhibit constraint on facial development 8,9 , they have comparatively diverse beak morphologies associated with a range of feeding and behavioural ecologies, in contrast to Mesozoic birds. Here we describe a crow-sized stem bird, Falcatakely forsterae gen. et sp. nov., from the Late Cretaceous epoch of Madagascar that possesses a long and deep rostrum, an expression of beak morphology that was previously unknown among Mesozoic birds and is superficially similar to that of a variety of crown-group birds (for example, toucans). The rostrum of Falcatakely is composed of an expansive edentulous maxilla and a small tooth-bearing premaxilla. Morphometric analyses of individual bony elements and three-dimensional rostrum shape reveal the development of a neornithine-like facial anatomy despite the retention of a maxilla-premaxilla organization that is similar to that of nonavialan theropods. The patterning and increased height of the rostrum in Falcatakely reveals a degree of developmental lability and increased morphological disparity that was previously unknown in early branching avialans. Expression of this phenotype (and presumed ecology) in a stem bird underscores that consolidation to the neornithine-like, premaxilla-dominated rostrum was not an evolutionary prerequisite for beak enlargement.

This study investigated the effects of preferred and non-preferred warm-up music listening conditions on subsequent exercise performance. A total of 12 physically active male and female participants engaged in a crossover, counterbalanced research design in which they completed exercise trials after 3 different warm-up experiences of (a) no music (NM), (b) preferred music (PREF), and (c) nonpreferred music (NON-PREF). Participants began warming up by rowing at 50% of of age-predicted heart rate maximum (HR max ) for 5 minutes while exposed to the three music conditions. Immediately following the warm-up and cessation of any music, participants completed a 2000-m rowing time trial as fast as possible. Relative power output, trial time, heart rate, rating of perceived exertion, and motivation were analyzed. Results indicated that, compared with NM, relative power output was significantly higher ( p   =    .018), trial time was significantly lower ( p   =    .044), and heart rate was significantly higher ( p   =    .032) during the PREF but not the NON-PREF condition. Rating of perceived exertion was not altered, regardless of music condition ( p  > .05). Motivation to exercise was higher during the PREF condition versus the NM ( p   =    .001) and NON-PREF ( p  <   .001) conditions. Listening to preferred warm-up music improved subsequent exercise performance compared with no music, while nonpreferred music did not impart ergogenic benefit.

The purpose of this study was to investigate balance and motor control in dancers and non-dancers with different foot positions. Physically active female dancers ( n = 11) and non-dancers ( n = 9) randomly completed two balance tests in a single visit: 1) Y-balance test (YBT), and 2) motor control test (MCT). Each test was completed with two different foot positions: 1) first ballet position in which heels were touching and feet were externally rotated to 140 degrees, and 2) sixth ballet position in which heels were spaced 10 cm apart and forward parallel. For the YBT, participants completed three attempts at anterior, posteromedial, and posterolateral reaches, which were averaged and standardized to limb length for a composite score. For the MCT, participants completed a multi-directional target test on a Biosway balance system, and accuracy and time to completion were analyzed. Findings revealed no differences in YBT score ( p = 0.255), MCT score ( p = 0.383), or MCT time ( p = 0.306) between groups in the sixth position. However, dancers displayed better YBT scores ( p = 0.036), MCT scores ( p = 0.020), and faster MCT times ( p = 0.009) in the first position. Results suggest that superior balance and motor control in dancers may be limited to less innate dance-specific foot positions.

The purpose of this study was to investigate the effects of nocebo administration on perceived soreness and exercise performance following unaccustomed resistance exercise. Untrained males were randomly assigned to one of two treatments: (1) control or (2) negative-belief. For the negative-belief group, participants were given a capsule before exercise containing 400 mg of an inert substance (gluten-free cornstarch) and were told the supplement would increase muscle soreness. The control group received no treatment. An algometer and pain scale was used to obtain soreness, and a goniometer was used to measure elbow range of motion (ROM). Participants completed an eccentric bicep curl pyramid with their non-dominant arm. Rate of perceived exertion (RPE) and repetitions were recorded. Then, 48 h after the initial exercise bout, participants repeated all procedures. Perceived soreness, ROM, average RPE, and total repetitions performed were analyzed. Perceived soreness was significantly higher in both control and negative-belief groups 48 h after exercise ( p < 0.001; η 2 = 0.23). ROM was significantly lower 48 h post in the negative-belief group ( p = 0.004; d = 1.83) while no differences existed for controls ( p = 0.999; d = 0.16). Average RPE was unaffected between groups ( p = 0.282; η 2 = 0.07). Total repetitions were significantly lower 48 h post in the negative-belief group ( p < 0.001; d = 2.51) while no differences existed for the controls ( p = 0.999; d = 0.08). Findings suggest that 48 h after unaccustomed resistance exercise, negative expectation does not worsen soreness but hinders ROM and exercise performance.

The fossil record of mammaliaforms (mammals and their closest relatives) of the Mesozoic era from the southern supercontinent Gondwana is far less extensive than that from its northern counterpart, Laurasia 1,2 . Among Mesozoic mammaliaforms, Gondwanatheria is one of the most poorly known clades, previously represented by only a single cranium and isolated jaws and teeth 1-5 . As a result, the anatomy, palaeobiology and phylogenetic relationships of gondwanatherians remain unclear. Here we report the discovery of an articulated and very well-preserved skeleton of a gondwanatherian of the latest age (72.1-66 million years ago) of the Cretaceous period from Madagascar that we assign to a new genus and species, Adalatherium hui. To our knowledge, the specimen is the most complete skeleton of a Gondwanan Mesozoic mammaliaform that has been found, and includes the only postcranial material and ascending ramus of the dentary known for any gondwanatherian. A phylogenetic analysis including the new taxon recovers Gondwanatheria as the sister group to Multituberculata. The skeleton, which represents one of the largest of the Gondwanan Mesozoic mammaliaforms, is particularly notable for exhibiting many unique features in combination with features that are convergent on those of therian mammals. This uniqueness is consistent with a lineage history for A. hui of isolation on Madagascar for more than 20 million years.

Williams, TD, Martin, MP, Mintz, JA, Rogers, RR, and Ballmann, CG. Effect of acute beetroot juice supplementation on bench press power, velocity, and repetition volume. J Strength Cond Res 34(4): 924-928, 2020-The purpose of this study was to examine the effects of acute beetroot juice (BRJ) supplementation on power, velocity, and repetitions to failure (RTF) during bench press exercise. Resistance-trained male subjects (n = 11) were recruited for this study. Using a double-blinded, counterbalanced, crossover study design, subjects were supplemented with either 70 ml of BRJ or placebo (PL; black currant juice) 2 hours before exercise. During each exercise trial, subjects began by completing 2 sets × 2 repetitions of bench press at 70% 1 repetition maximum (1RM) with maximum explosive intent. Barbell velocity and power were measured using a linear position transducer. Subjects then completed 3 sets × RTF at 70% 1RM separated by 2 minutes of rest between each set. Maximum mean power, velocity, and repetitions were analyzed. Mean velocity (p = 0.011; effect size [ES] = 0.54) and mean power (p = 0.015; ES = 0.51) were significantly higher with BRJ when compared with PL. Total RTF (p = 0.002; ES = 0.46) was higher during the BRJ condition vs. PL. Results indicate that acute BRJ supplementation positively impacts velocity, power, and total repetitions during free-weight bench press exercise.

The purpose of this study was to examine the effects of protective football headgear on peripheral vision reaction time and visual target detection. Twenty-five Division I NCAA football players (age = 20.5 yrs ± 0.9, height = 185.9 cm ± 6.8, body mass = 99.2 kg ± 19.2, BMI = 29.6 ± 4.5) participated. In a crossover counterbalanced study design, subjects participated in one visit with three conditions: Baseline (BL) without headgear, helmet only (HO), helmet with an eye shield (HE). Subjects completed a 1-min peripheral vision reaction time test for each condition separated by 3-min recovery periods. Tests were administered using a 64 light Dynavision D2 Visuomotor board. Target detection (total hit score) was higher during BL than HO (p < 0.001) and HE (p < 0.001). Average (p < 0.001), peak (p < 0.001), minimum (p < 0.001), and median (p < 0.001) peripheral reaction times were faster during BL than HO and HE. No significant differences were observed for any measures between HO and HE conditions (p > 0.05). Findings indicate that protective football headgear impaired reaction time to peripheral visual stimuli. The addition of an eye shield to the helmet had a small non-significant effect on reaction time and target detection. These results may hold important implications in helmet design and player safety.

The purpose of this study was to examine the effects of listening to preferred or non-preferred music on repeated sprint performance. Fourteen physically active males (ages 18-25 years) were recruited for this study. In a counterbalanced crossover study design, participants completed two separate visits. During each visit, participants listened to either preferred or non-preferred music and completed 3 × 15 s Wingate Anaerobic Tests (WAnTs) separated by 2 min active recovery periods. Each visit was separated by a minimal recovery period of 48 h. Anaerobic performance measures, heart rate, rate of perceived exertion (RPE), and motivation were analyzed. Mean power ( p = 0.846, effect size (ES) = 0.019), anaerobic capacity ( p = 0.686, ES = 0.058), and total work ( p = 0.677, ES = 0.039) were not significantly different between preferred and non-preferred music conditions. Mean heart rate ( p = 0.608; ES = 0.125) was also unchanged. Motivation to exercise ( p < 0.001; ES = 1.520) was significantly higher in the preferred music condition. Additionally, the rate of perceived exertion (RPE) ( p = 0.028; ES = 0.540) was significantly lower during the preferred music condition. Our results show that listening to preferred music showed no ergogenic benefit during repeated anaerobic cycling sprints when compared to non-preferred music. However, preferred music increased motivation to exercise and decreased perceived exertion. The results from this study could hold important implications for the application of music and enduring repeated high-intensity sprint exercise.