Introduction: Acute ketone monoester (KE) supplementation affects exercise responses but there are equivocal data regarding the effects on exercise efficiency. We examined the effect of ketone monoester ingestion on exercise efficiency during cycling and probed further the influence of supplement dose and exercise intensity. This study was registered prior to data collection at ClinicalTrials.org (NCT05665855). Methods: Twenty-eight trained adults were recruited [16 males, 12 females; peak oxygen uptake (V̇O2peak): 59±11 ml·kg-1·min-1]. Participants completed three experimental trials in a randomized, crossover, and double-blinded manner, each separated by ~1 week. Participants ingested either a 0.3 (KE-LO) or 0.6 g/kg (KE-HI) body mass dose of KE or a flavour-matched placebo (PLAC) ~30 min prior to exercise. The incremental cycling protocol involved a 3-minute warm-up, three 5-minute stages at 75%, 100%, and 125% of individual ventilatory threshold, and a ramp increase to volitional exhaustion. Expired gases and heart rate were measured continually during exercise. Results: Venous blood [ß-hydroxybutyrate], the major circulating ketone body, was higher in both KE conditions compared to PLAC and also different between conditions (3.0±1.1 and 2.3±0.6 vs 0.2±0.1 mM; all p<0.05). There were no differences in submaximal exercise V̇O2, exercise economy, gross efficiency, or delta efficiency between conditions (all p>0.05). Submaximal exercise heart rate and ventilation were higher in both KE conditions compared to PLAC (141±11 and 141±12 vs 137±12 beats/min; 63±14 and 62±13 vs 60±13 L/min, respectively; all p<0.05). Peak power output at V̇O2peak was lower in KE-HI compared to both KE-LO and PLAC (329±60 vs 339±62 and 341±61 W; both p<0.05). Conclusion: KE supplementation did not alter exercise efficiency during submaximal cycling. KE ingestion increased cardiorespiratory stress during submaximal exercise and the higher dose reduced peak aerobic power output. Future studies should investigate the mechanisms by which KE ingestion alters exercise responses. / Thesis / Master of Science (MSc) / Endurance exercise performance is determined by many variables including the efficiency of the individual. This can be measured during cycling by calculating the ratio of oxygen uptake relative to power output. Ketone supplements have been suggested to alter exercise efficiency. We investigated this issue by having trained adults complete an incremental cycling protocol on three occasions. Before exercise the participants ingested either a small or large dose of a ketone supplement or a taste-matched placebo drink. Exercise efficiency was not different between the conditions but ventilation rate and heart rate were higher during the ketone supplemented trials compared to the placebo. The power output that the participants could achieve at maximal exercise was reduced in the high dose ketone condition. Our study does not support the use of ketone supplements as a strategy to enhance endurance exercise performance. Future studies should investigate the mechanisms by which ketones affect exercise responses.

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Syfte Syftet med litteraturstudien var att se om längdskidåkares förmåga att utveckla kraft eller effekt kan relateras till prestation samt om en förändring av dessa förmågor ger en samtidig förändring i prestation. Metod Via databaserna PubMed, Web of Science och SPORTDiscus gjordes det en litteratursökning. För att inkluderas så skulle artiklarna ha undersökt: 1) träning för att öka styrka eller effektutveckling, 2) längdskidåkare, 3) prestationsförmåga i längdskidåkning. Resultat Totalt granskades tolv träningsstudier. Nio studier visade på en ökad styrka samtidigt som de visade på en förbättrad prestation. Fyra studier visade på ett samband mellan prestation och kraft- eller effektutveckling. Det finns dock ingen korrelation mellan förändrad styrka och förändrad prestation. Slutsatser Förmågan att utveckla kraft/effekt är viktig för prestationsförmågan inom längdskidåkning. Däremot innebär inte en förändring av styrka via styrketräning motsvarande förändring av prestationsförmågan.

Thesis advisor: Ruth Langer / This dissertation creates a Jewish theology of asceticism focused on articulating the ideals toward which Jewish observant life is directed, a method for reflecting on the ‘ends’ of a Jewish life well lived in relationship to practice. I apply this theological asceticism to an analysis of Jewish liturgical prayer (tefilat keva), arguing that it is a desire-forming practice that causes practitioners to reimagine human flourishing and what leads to true satisfaction. My approach to this topic is modeled on a careful analysis and evaluation of the Anglican theologian Sarah Coakley’s “new asceticism” in light of Charles Taylor’s “maximal demand.” I augment Coakley’s definition of asceticism to fit a Jewish theological anthropology articulated by Rabbi Israel Salanter. I then apply this ascetic discourse to the study of the daily practice of liturgy. The Jewish liturgical asceticism I develop draws together elements from the Catholic James Fagerberg’s liturgical theology, the Presbyterian theologian James K. A. Smith’s theories about how liturgy forms a social-imaginary, and R. Israel Salanter’s teachings on the formation of desire (ta’avah) through the practice of hitpa’alut. The dissertation ends with an application of this method for theologically reflecting on the desire forming power of a daily prayer life through a close reading of elements of the weekday morning service, shacharit. This dissertation offers a Jewish theological account of the formative power of liturgical prayer on human desire. It also creates an approach for thinking more broadly about desire formation as a key component in the ideal goals of a normative Jewish lifestyle. This theological project will benefit communities of practice looking to better understand the wisdom of their inherited spiritual practices, educators and communal rabbis looking to commend traditional Jewish ways of life, Jewish theologians looking for an approach to discussing the ideals within Jewish life in a way that stays rooted in practice, and scholars of Jewish liturgy who are looking for methods for studying liturgy as a formative act and not merely an historical text. / Thesis (PhD) — Boston College, 2022. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Theology.

As finite element discretizations ever grow in size to address real-world problems, there is an increasing need for fast algorithms. Nowadays there are many GPU/CPU parallel approaches to solve such problems. Multigrid methods can be used to solve large-scale problems, or even better they can be used to precondition the conjugate gradient method, yielding better results in general. Capabilities of multigrid algorithms rely on the effectiveness of the inter-grid transfer operators. In this thesis we focus on the aggregation approach, discussing how different aggregation strategies affect the convergence rate. Based on these discussions, we propose an alternative parallel aggregation algorithm to improve convergence. We also provide numerous experimental results that compare different aggregation approaches, multigrid methods, and conjugate gradient iteration counts, showing that our proposed algorithm performs better in serial and parallel. / Modeling real-world problems incurs a high computational cost because these mathematical models involve large-scale data manipulation. Thus we need fast and efficient algorithms. Nowadays there are many high-performance approaches for these problems. One such method is called the Multigrid algorithm. This approach models a physical domain using a hierarchy of grids, and so the effectiveness of these approaches relies on how well data can be transferred from grid to grid. In this thesis, we focus on the aggregation approach, which clusters a grid’s vertices according to its connections. We also provide an alternative parallel aggregation algorithm to give a faster solution. We show numerous experimental results that compare different aggregation approaches and multigrid methods, showing that our proposed algorithm performs better in serial and parallel than other popular implementations.

This study is an investigation into methods of developing ergonomic guidelines for automotive assembly tasks involving insertion of small parts. The study was conducted in four major parts: 1) a method of determining and evaluating subjective exertion limits was modified and tested, 2) a large dataset was collected from an industrial population in 10 simulated assembly line tasks, 3) a smaller dataset was collected from a student population to assess hand dominance effects, and 4) strength data obtained was compared with a strength prediction model to determine if the model could predict manual insertion forces. The traditional method of psychophysical data collection requires participants to extrapolate sensations from a relativity short session to judge if the task could be done for a much longer period. Maximum acceptable limits (MALs) are typically derived from having participants adjust a weight, resistance, or frequency to an acceptable level. The present study evaluated a relatively new method of collecting MAL data for simple, single-digit exertions where participants were asked to determine an MAL by self-adjusting and then regulating to maintain the exertion level. Results showed that MAL values obtained from a series of self-regulated exertions were independent of both analysis method and duration (5 minutes vs. 25 minutes) used for evaluation, and that the method was repeatable both within and between sessions. Ergonomic guidelines are often obtained from the strength capacity for a certain task, as it is important to ensure that workers possess sufficient strength to accomplish a task. As task demands increase, however, a larger percentage of a worker's strength capability in required, and other factors, such as performance and worker comfort, tend to be compromised. In this work, both strength capacity and subjective limits were obtained for a variety of simulated tasks to facilitate development of guidelines for the specific tasks. The relationship between these two measures (maximum force, acceptable force) was determined, and acceptable limits were found to be approximately 55% of population strength capacity, with correlations (R2) ranging from 0.40 to 0.60 depending on the task, suggesting the subjective limits and strength capacity are related in these tasks. Hand dominance was found to have a small (5%), but significant (p = 0.006) effect on strength capability, and no significant effect on subjective limit. Biomechanical strength prediction models can be used to assess loads placed on the human performing various tasks. One of the more popular models, Three-Dimensional Static Strength Prediction Program, is often used for heavy material handling tasks, such as lifting or pushing. The tasks studied presently, however, are manual insertions, requiring localized force application rather than whole body exertion. The prediction capabilities of this strength prediction model were compared with strength values obtained from the simulated assembly tasks. Results indicated that the model was not successful when predicting localized force, accounting for only 40% of the observed variance in strength (R2 = 0.4) / Master of Science

Introduction Researchers have, for decades, contributed to an increased collective understanding of the physiological demands in cross-country skiing; however, almost all of these studies have used either non-elite subjects and/or performances that emulate cross-country skiing. To establish the physiological demands of cross-country skiing, it is important to relate the investigated physiological variables to the competitive performance of elite skiers. The overall aim of this doctoral thesis was, therefore, to investigate the external validity of physiological test variables to determine the physiological demands in competitive elite cross-country skiing. Methods The subjects in Study I – IV were elite male (I – III) and female (III – IV) cross-country skiers. In all studies, the relationship between test variables (general and ski-specific) and competitive performances (i.e. the results from competitions or the overall ski-ranking points of the International Ski Federation (FIS) for sprint (FISsprint) and distance (FISdist) races) were analysed. Test variables reflecting the subject’s general strength, upper-body and whole-body oxygen uptake, oxygen uptake and work intensity at the lactate threshold, mean upper-body power, lean mass, and maximal double-poling speed were investigated. Results The ability to maintain a high work rate without accumulating lactate is an indicator of distance performance, independent of sex (I, IV). Independent of sex, high oxygen uptake in whole-body and upper-body exercise was important for both sprint (II, IV) and distance (I, IV) performance. The maximal double-poling speed and 60-s double-poling mean power output were indicators of sprint (IV) and distance performance (I), respectively. Lean mass was correlated with distance performance for women (III), whereas correlations were found between lean mass and sprint performance among both male and female skiers (III). Moreover, no correlations between distance performance and test variables were derived from tests of knee-extension peak torque, vertical jumps, or double poling on a ski-ergometer with 20-s and 360-s durations (I), whereas gross efficiency while treadmill roller skiing showed no correlation with either distance or sprint performance in cross-country skiing (IV). Conclusion The results in this thesis show that, depending on discipline and sex, maximal and peak oxygen uptake, work intensity at the lactate threshold, lean mass, double-poling mean power output, and double-poling maximal speed are all externally valid physiological test variables for evaluation of performance capability among elite cross-country skiers; however, to optimally indicate performance capability different test-variable expressions should be used; in general, the absolute expression appears to be a better indicator of competitive sprint performance whereas the influence of body mass should be considered when evaluating competitive distance performance capability of elite cross-country skiers.

Tyrimo pagrindimas: sportininkų judėjimo gebėjimai vyksta dalyvaujant paskutiniai grandžiai pėdos lenkiamiesiems ir tiesiamiesiems raumenims (Нечаев, 2011). Didelio meistriškumo graikų-romėnų imtynininkų raumenų kraujotakos mobilizacijos ir atsigavimo ypatybės yra artimesnės ištvermės sporto šakų atstovams nei sprinto grupės sportininkų ypatybėms. (Ežerskis, 2009). Tikslas- išanalizuoti skirtingos adaptacijos fiziniams krūviams vyrų ir merginų pėdų lenkiamųjų raumenų funkcinius ypatumus. Hipotezė: pėdos lenkiamųjų raumenų ištvermė priklauso nuo maksimalios valingos jėgos dydžių, kuo didesnė jėga, tuo mažesnė ištvermė. Metodai: dinamometrija, literatūros šaltinių studija, statistinė analizė. Aptarimas ir Išvados: dvikovos sportininkių, ištvermės ir greitumo jėgos atstovų tarpusavyje kairės ir dešinės kojos jėga nesiskyrė yra proporcingų dydžių. Ištvermės sportininkų vyrų pėdos lenkiamųjų raumenų kojų jėga buvo ženkliai didesnė už dvikovos, sporto šakų, tačiau mažesnė nei greitumo jėgos atstovų. Dvikovos sporto šakų sportininkių ir ištvermės atstovų bei greitumo jėgos sportininkų MRI rodikliai skyrėsi neženkliai, tačiau jėga buvo mažesnė Nuo jėgos dydžio priklauso ištvermės trukmė. Esant didesnei jėgai ištvermės trukmė mažėja. Pagal santykio MVJ/MRI reikšmes visos priklauso stajerio tipui. Tyrimo uždaviniai: 1. Nustatyti dvikovos sporto šakų moterų ir vyrų, pėdos lenkiamųjų raumenų maksimalios valingos jėgos dydžius. 2. Nustatyti dvikovos sporto šakų moterų ir vyrų, pėdos... [toliau žr. visą tekstą] / Introduction: Atlete's movement depends on the activity of the foot flexor muscle strength and endurance. High craftsmanship Greco- Roman wrestlers muscle blood mobilization and recovery features are closer to endurance sports disciplines than sprint atlete properties. Aim: Analysis the different physical exertion adaptation of men and a girl's foot muscle flexion functional features. Hypothesis: foot flexor muscle endurance duel sport athletes are the same length as the representatives of the endurance strength but size was lager. Methods: dynamometry, literature study, a statistical analysis. Discussion and Conclusion: The duel athletes, endurance and speed power representatives each other left and right leg power is proportional not different sizes. Endurance representatives of men's foot flexor muscles leg strength was significantly higher than the duel sports, but less than the speed force representatives. Duel sport athletes and endurance representatives maximal muscle endurance characteristics differed slightly, but the force was smaller size of the force depends on endurance time. At higher power of endurance time decreases. According to the ratio of maximal voluntary contruction / maximal muscle endurance values all belong stajer type. Exploratory tasks : 1)set duel sports for men and women, foot flexion maximum voluntary muscle force figures. 2)Set duel sports for men and women, foot flexor muscle endurance for maximum muscle size. 3)Identify and analyze the duel... [to full text]

Our study focuses on the connection between existence of a punctum fixum (or point of support) and respiratory muscle strength. Respiratory muscles execute both respiratory and postural function. Therefore, their strength defines both of these functions. We summarize contemporary knowledge about respiratory and postural functions of the respiratory muscles, their interactions and the connection to postural stability. We used a spirometry assesment of maximal respiratory pressures (PImax and PEmax). The values of PImax (PEmax respectively) retrieved in stance and during water immersion without stable support were compared. We found statistically significant differences. PImax was lower in the water immersion situation (p=0,0009; p≤0,05) and so was PEmax (p=0,0076; p≤0,05). Regarding the results, we suppose a significant influence of punctum fixum presence/absence on maximal respiratory muscle strength. Possible reasons are discussed.

ABSTRACT Male subjects are invariably used to study the physiological determinants of middle distance running performance. Studies that do include females have examined only the aerobic contribution to middle distance running performance. The aim of the present study was to investigate aerobic, anaerobic and muscle function factors that could be used to predict middle distance running performance in female runners. This study was performed at an altitude of 1800m. Eleven middle distance female runners aged 18-20 were selected for the study. Aerobic capacity was assessed by measuring the maximal oxygen consumption (VO2max), running velocity at maximal oxygen consumption (vVO2max), running economy (RE) and onset of blood lactate accumulation (OBLA). The blood lactate curve of each subject was constructed by relating the oxygen consumption, to the plasma lactate concentrations. Anaerobic capacity was determined by measuring the maximum accumulated oxygen deficit (MAOD) on a treadmill. Muscle function was assessed by having the subjects cycle as fast as possible against changing brake weights ranging from heavy to light using a Monark cycle ergometer. The brake force (kg) was related to velocity (rpm).