Cardiovascular responses and tolerance to an orthostatic stress were examined in eight men before and after eight months of endurance exercise training. Following training, maximal oxygen consumption and blood volume were increased, and resting heart rate reduced. Orthostatic tolerance was reduced following training in all eight subjects. It was concluded that prolonged endurance training decreased orthostatic tolerance and this decrease in tolerance appeared associated with attenuated baroreflex sensitivity and alterations in autonomic balance secondary to an increased parasympathetic tone noted with training.

Swedish executives are in the pursuit of self-improvement. During the last two decades, extreme athleticism, practices like meditation and visiting retreats have been an increasingly common context within this pursuit, despite being costly in terms of time or simply being perceived as extreme. In an attempt to further understand these pursuits, the study seeks to answer the research question: How are the leader’s pursuit of self-improvement influencing leadership and what does it signal? The theoretical point of departure is previous research on athleticism and mindfulness amongst executives, through the perspective of signaling theory and charismatic leadership theory. The study is qualitative in nature with an abductive approach and consists of interviews with ten executives as well as a discourse of Swedish printed press. The data have been coded using the Gioia-methodology. The empirical findings consist of nine aggregated dimensions explaining executive behavior. How they began with their practice, what health benefits they achieved, what attributes were strengthened, the positive effect on leadership, the costs of their practice, how identity is involved, their own awareness of their practice, how they believed it influenced leadership, and what their leadership aspirations were. After analysis of the pursuits, it is concluded that the pursuits signal certain underlying qualities and attributes, an identity, and competence to lead oneself and others. Through actions inspired by their pursuits, signaling is reinforced and become signals of the organization as well as the individual leader and his or her leadership.

Critical Power (CP) is the greatest power that a person can sustain for prolonged periods of time while maintaining steady state conditions. Work-prime (W’) is the amount of work that can be tolerated when exercising in non-steady-state conditions above CP. A person’s CP and W’ strongly influence the metabolic response and tolerance to exercise. PURPOSE: Compare the effect of equal amounts of moderate intensity continuous training (MICT) and high intensity interval training (HIIT) on CP and W’. Critical Power (CP) is the greatest power that a person can sustain for prolonged periods of time while maintaining steady state conditions. Work-prime (W’) is the amount of work that can be tolerated when exercising in non-steady-state conditions above CP. A person’s CP and W’ strongly influence the metabolic response and tolerance to exercise. PURPOSE: Compare the effect of equal amounts of moderate intensity continuous training (MICT) and high intensity interval training (HIIT) on CP and W’. METHODS: Twenty-two (10 female) untrained, young (26.4 ± 0.9 years) adults completed 8 weeks of cycling training (40 min, 3  per week) administered as either MICT cycling (44% max work rate achieved during a maximal graded exercise test; GXTmax) or HITT cycling (4 bouts at 80% GXTmax for 4 min with recovery intervals between). Cycling V̇O2max, CP, W’ and Anaerobic Capacity (i.e., Wingate) were determined before and after training. Specifically, CP was assessed with the work-over-time method derived from 4–5 constant-power tests to exhaustion. RESULTS: MICT (n = 11) and HIIT (n = 11) groups completed the same amount of work over the course of the training (P = 0.76). CP significantly increased in both groups, but to a greater extent in the HIIT group (MICT: 15.7 ± 3.1% vs. HIIT: 27.5 ± 4.3%; P = 0.04). The work that could be performed above CP (i.e., W’) was not significantly impacted by training (p = 0.76). V̇O2max significantly increased in both groups (P < 0.01), and the magnitude tended to be greater in the HIIT group (MICT: 8.3 ± 2% vs. HIIT: 14 ± 2.6%; P = 0.09). Interestingly, the training-induced change in CP was not significantly related to the training-induced change in V̇O2max. The training-induced increase in CP exhibited a positive curvilinear relationship with the training intensity, expressed as a percentage of the initial CP, with those performing the same workout at a greater percentage of CP exhibiting greater training-induced increases in CP (R2 = 0.49, P < 0.01). CONCLUSION: HIIT elicits approximately twice the increase in CP than an equal amount of MICT in untrained young adults. Moreover, the magnitude of increase in CP is strongly related to the intensity of the exercise, relative to CP, even when exercising at the same percentage of GXTmax. Thus, exercise may be more effectively prescribed relative to CP, rather than V̇O2max or GXTmax.

Denna litteraturstudie tar sikte på att belysa hur proteinkonsumtion påverkar en atlets fysiska uthållighetsförmåga. För att kunna maximera sin uthållighetsprestation behöver atleter protein för att bland annat ersätta använd energi. Atleter behöver även protein för att tillgodose musklerna med essentiella aminosyror för optimal återuppbyggnad. Det resulterar i att proteinintaget delvis blir avgörande för hur kroppen svarar på träningsinsatsen. Beroende på typ av sportutövning såväl som individuella skillnader så har dock olika atleter olika nutritionella behov. Folkhälsomyndigheten följer WHO:s rekommendation gällande ett generellt dagligt proteinintag på 0,8gram per kilo kroppsvikt för vuxna. Elitidrottare rekommenderas däremot ett dagligt proteinintag på 1,4–1,8gram protein per kilo kroppsvikt. Studier som analyserar nutrition i relation till fysisk prestationsförmåga baseras främst på manliga studiedeltagare. Det har dock etablerats att det finns könsbaserade skillnader när det kommer till metabolism under uthållighetsträning. Män är mer beroende av kolhydrat- och proteinkällor under uthållighetsträning än vad kvinnor är. Detta beror sannolikt delvis på skillnader i koncentrationsnivåer av hormonet östrogen. Sammanfattningsvis visar resultaten att idrottande atleter har ett högre proteinbehov än människor som inte tränar. Ett ökat proteinintag visar sig dock inte systematiskt öka en atlets uthållighetsprestation. Däremot finns en samstämmighet kring att ett ökat proteinintag reducerar stressmarkörer vid en hög fysisk belastning. Detta tyder på att proteinmängden påverkar prestationsmöjligheten sett under en längre tid. Dessutom visar det att proteinintaget reducerar skaderisken, vilket bör vara essentiellt för atleter vars träningsmöjligheter minimeras vid skada. Därtill tyder granskade studier på att humöret efter fysisk ansträngning förbättras med ett ökat proteinintag vilket också är av intresse. Den proteinmängd som bör intas av atleter som vill maximera sin uthållighetsträning är 1,45g/kg/d för kvinnliga atleter och 1,74g/kg/d för manliga atleter. Båda värden är inom spannet som folkhälsomyndigheten rekommenderar för elitidrottare. Men det är av vikt att i framtiden belysa könsbaserade skillnader för att främja mer jämlika kunskapsförhållanden mellan kvinnliga och manliga atleter.

In an attempt to improve aerobic and anaerobic performance, athletes and fitness enthusiasts consume a variety of supplements. Because of this, energy drinks are quickly becoming more and more popular every day. Despite its highly addictive nature, caffeine, which is the main active ingredient in energy drinks, is gaining recognition as an ergogenic aid. However, due to the many factors that affects the action of caffeine, and because the research on caffeine and anaerobic performance is limited, the potential for studying energy drinks and anaerobic performance is quite large. PURPOSE: To determine if a commercially available energy drink has any ergogenic effects on lower body and upper body resistance exercise performance. METHODS: In a block randomized, double-blind, placebo-controlled, crossover study thirteen recreationally trained male and female volunteers (mean ± SD age = 22.5 ± 3.4 years) performed 4 sets of the leg press and 4 sets of the bench press exercises (at 80% of 1 RM with all sets separated by 2 minutes). Acting as their own controls, participants were tested on each dependent variable (i.e., bench press total volume, leg press total volume and total workout volume) twice, after ingesting a Venom® Energy Drink and after ingesting a placebo drink. RESULTS: Data were tested via a dependent samples t-test with p value set at < 0.05. No significant differences were found for any of the three dependent variables. DISCUSSION: The major finding of this study is that consumption of a Venom® Energy Drink does not produce an ergogenic effect by improving anaerobic exercise performance when the exercises are performed forty-five minutes following ingestion. Future studies should focus more on examining the factors behind the actions of caffeine. More specifically, the exercise performed, the training status of the participants, individual differences of the participants, and the dose of caffeine.

Identification, objectification, and determination of performance criteria for elite soccer players. Aim: Identification of key point indicators (KPI) of young soccer players with a focus on objectifying and determining the possibility of achieving the highest level of performance. Methods: The study included 157 soccer players, who were then divided into five age groups (U21, U19, U18, U17 and U16) and three performance groups (Elite - 1st league players, Sub-elite - 2nd league players, Amateur - 3rd league and lower performance levels players). Within laboratory diagnostics, the following areas were evaluated: body composition (bioimpedance method), postural stability (using pressure plates), explosive power of the lower limbs (three types of vertical jumps), strength and power of knee extensors and flexors (using isokinetic dynamometry) and the value of the maximum aerobic capacity VO2max (using the pulmonary ventilation exercise test). Within the field diagnostics, the areas of acceleration time (sprint at 5 and 10 m), maximum speed (sprint at 20 m flight), time in the test of change of direction (Agility 505 test and K-test) and values of endurance ability (Yo- Yo intermittent recovery test level 1 and 2). The diagnosed data were then processed in the statistical program RStudio® (USA) using...

京都大学 / 0048 / 新制・論文博士 / 博士(農学) / 乙第12877号 / 論農博第2804号 / 新制||農||1028(附属図書館) / 学位論文||H26||N4876(農学部図書室) / 31595 / (主査)教授 伏木 亨, 教授 保川 清, 教授 安達 修二 / 学位規則第4条第2項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第19042号 / 農博第2120号 / 新制||農||1032(附属図書館) / 学位論文||H27||N4924(農学部図書室) / 31993 / 京都大学大学院農学研究科食品生物科学専攻 / (主査)教授 伏木 亨, 教授 保川 清, 教授 金本 龍平 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

RED-S is a syndrome that stems from low energy availability (LEA) in athletes. It can impact numerous physiological and psychological functions, as well as negatively affect performance. Because RED-S is a relatively new syndrome, there are few studies showing the impact of RED-S on performance and physiological factors. The aim of this systematic review was to examine the consequences of induced LEA in relation to RED-S in male athletes. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, Five studies were deemed eligible based on inclusion and exclusion criteria. Studies measured risk of RED-S through body composition, bone mineral density, clinical biomarkers, and performance. Studies ranged in duration from 2- 8 weeks with a decrease in energy availability of 50% or 25%. Of the five studies investigated, data showed significant changes lactate metabolism and IGF-1,non-significant changes in body composition, and inconclusive changes in performance.