Att utveckla atleter bygger på förmågan att som ledare kunna skapa goda relationer till sina atleter. En viktig del i att skapa goda relationer handlar om att kunna individanpassa sitt bemötande, beroende på den enskilda individens behov. Syftet var att studera sambandet mellan föredraget ledarskapsbeteende och personlighet, kön, ålder samt typ av idrott (lag- och individuell idrott). Idrottare N=113, 25st män och 88st kvinnor svarade på en online-enkät innehållande demografisk information, Leadership Scale for Sports och NEO Five-factor Inventory. Personlighetsegenskapen Trevlighet hade positivt samband med Autokratiskt ledarskapsbeteende och negativt samband med Positiv Feedback, Demokratiskt- samt Socialt stödjande ledarskapsbeteende. Neuroticism hade ett positivt samband med Autokratiskt ledarskapsbeteende och Extroversion hade ett negativt samband med Instruerande ledarskapsbeteende. Kvinnor föredrar Socialt stödjande ledarskapsbeteende mer än män och män föredrar Demokratiskt ledarskapsbeteende mer än kvinnor. Äldre personer föredrar Socialt stödjande ledarskapsbeteende mer än yngre. I föreliggande studie finns inget entydigt resultat eller distinkt samband mellan flera individuella faktorer, som pekar på att någon av de fem olika ledarskapsdimensionerna skulle vara mer föredraget framför de andra. De individuella faktorerna kan förklara vissa behov hos atleter, men dess betydelse behöver först identifieras av både atleten själv och ledaren, för att därefter kunna tillämpa ett passande beteende. / Developing athletes is based on the ability as a leader to create good relationships with their athletes.!An important part of creating good relationships is about being able to adapt one's attitude to the individual, depending on the individual's needs. The objective of the study was to examine the relationship between preferred leadership behaviour and personality, gender, age and type of sport (team and individual sport). Athletes N=113, 25 men and 88 females answered an online-survey containing demographic information, Leadership Scale for Sports and NEO Five-factor Inventory. Agreeableness had a positive correlation with Autocratic leadership and a negative correlation with Positive Feedback, Democratic leadership and Social support. Neuroticism had a positive correlation with Autocratic leadership and Extroversion had a negative correlation with Instructive Leadership. Women prefer Social support more than men and men prefer Democratic leadership more than women. Older people prefer Social support more than younger people. In the present study, there is no unambiguous result or distinct relationship between several individual factors, which indicates that one of the five different leadership dimensions would be more preferred over the others. The individual factors may explain certain needs of athletes, but their meaning must first be identified by both the athlete and the leader, in order to apply an appropriate behavior.

Bakgrund: Vitamin D är en solskensvitamin eftersom den bildas naturligt i kroppen när huden exponeras av solen. Vitamin D består av två fettlösliga former ergokalciferol (D2) och kolekalciferol (D3. Vitamin D är ett grundläggande komplement för att bevara en god hälsa och prestation. Syfte: Att undersöka vitamin D påverkan på fysisk prestation hos uthållighetsidrottare. Metod: Artikelsökningar på PubMed och Sport Discus gjordes 30/3 - 2/4 för att undersöka syftet med studien. Sammanlagt inkluderades 6 studier som undersökte vitamin D påverkan på fysisk prestation hos uthållighetsidrottare. Två kvalitetsbedömningar gjordes av studier för att undersöka om de uppfyller grundläggande kvalitetskrav. Resultat: Studierna genomförde fysiska tester och innehöll olika typ av uthållighetsidrottare, såsom löpare, cyklister, simmare, roddare, elitidrottare. Effekter av vitamin D på fysisk prestation var bland annat förbättrad muskelåterhämtning, muskelstyrka, snabbhet och syreupptagning. Konklusion: Vitamin D har positiva effekter på fysisk prestation hos kvinnliga och manliga uthållighetsidrottare. / Background: Vitamin D is a sunshine vitamin because it is formed naturally in the body when the skin is exposed to the sun. Vitamin D consists of two fat-soluble forms, ergocalciferol (D2) and cholecalciferol (D3). Vitamin D is a basic supplement for maintaining good health and performance. Purpose: To investigate the impact of vitamin D on the physical performance of endurance athletes. Method: Article searches were made in PubMed and Sport Discus 30/3-2/4 to investigate the purpose of the study. Totally 6 studies were included that have investigated the impact of vitamin D on the physical performance of endurance athletes. Two quality assessments were made on the studies to investigate whether they meet basic qualification requirements. Result: The studies performed physical tests and included different types of endurance athletes such as runners, cyclists, swimmers, rowers, elite athletes. Effects of vitamin D on physical performance included improved muscle recovery, muscle strength, speed, and oxygen uptake. Conclusion: Vitamin D has positive effects on physical performance in female and male endurance athletes.

The purpose of the study was to compare the physiological responses of skeletal muscle to a resistance training (RT) program using repetition maximum (RM) or relative intensity (RISR). Fifteen well-trained males underwent RT 3 d·wk−1 for 10 weeks in either an RM group (n = 8) or RISR group (n = 7). The RM group achieved a relative maximum each day, while the RISR group trained based on percentages. The RM group exercised until muscular failure on each exercise, while the RISR group did not reach muscular failure throughout the intervention. Percutaneous needle biopsies of the vastus lateralis were obtained pre-post the training intervention, along with ultrasonography measures. Dependent variables were: Fiber type-specific cross-sectional area (CSA); anatomical CSA (ACSA); muscle thickness (MT); mammalian target of rapamycin (mTOR); adenosine monophosphate protein kinase (AMPK); and myosin heavy chains (MHC) specific for type I (MHC1), type IIA (MHC2A), and type IIX (MHC2X). Mixed-design analysis of variance and effect size using Hedge’s g were used to assess within- and between-group alterations. RISR statistically increased type I CSA (p = 0.018, g = 0.56), type II CSA (p = 0.012, g = 0.81), ACSA (p = 0.002, g = 0.53), and MT (p < 0.001, g = 1.47). RISR also yielded a significant mTOR reduction (p = 0.031, g = −1.40). Conversely, RM statistically increased only MT (p = 0.003, g = 0.80). Between-group effect sizes supported RISR for type I CSA (g = 0.48), type II CSA (g = 0.50), ACSA (g = 1.03), MT (g = 0.72), MHC2X (g = 0.31), MHC2A (g = 0.87), and MHC1 (g = 0.59); with all other effects being of trivial magnitude (g < 0.20). Our results demonstrated greater adaptations in fiber size, whole-muscle size, and several key contractile proteins when using RISR compared to RM loading paradigms.

This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). Cytokine and hormone concentrations can be linked to the manipulation of training variables and to subsequent alterations in performance. Subjects: Nine D-1 collegiate throwers and 4 control subjects participated in this preliminary and exploratory report. Methods: Hormone (testosterone (T) and cortisol (C)) and adipokine (adiponectin, leptin, and resistin) measurements were taken at weeks 1, 7, and 11 for the throwers and weeks 1 and 11 for the control group. The throwers participated in an 11-week periodized resistance training and throws program during the fall preparatory period. Volume load was recorded throughout the study. Results: Hormone values did not exhibit statistically significant changes across time; however, there were notable changes for C, the testosterone to cortisol ratio (T:C), and adiponectin. Conclusions: T:C was increased as volume load decreased, and adiponectin increased in concert with decreases in C and increases in the T:C, possibly suggesting a lesser degree of obesity-related inflammation and a higher degree of “fitness” and preparedness.

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.

The ability to produce force rapidly has the potential to directly influence sprinting performance through changes in stride length and stride frequency. This ability is commonly referred to as the rate of force development (RFD). For this reason, many elite sprinters follow a combined program consisting of resistance training and sprint training. The purpose of this study was to investigate the strength, endocrine and body composition adaptations that occur during distinct phases of a block periodized training cycle in a 400 m Olympic level sprinter. The athlete is an elite level 400 m male sprinter (age 31 years, body mass: 74 kg, years of training: 15 and Personal Best (PB): 45.65 s). This athlete completed four distinct training phases of a block periodized training program (16 weeks) with five testing sessions consisting of testosterone:cortisol (T/C) profiles, body composition, vertical jump, and maximum strength testing. Large fluctuations in T/C were found following high volume training and the taper. Minor changes in body mass were observed with an abrupt decrease following the taper which coincided with a small increase in fat mass percentage. Jump height (5.7%), concentric impulse (9.4%), eccentric impulse (3.4%) and power ratio (18.7%) all increased substantially from T1 to T5. Relative strength increased 6.04% from T1 to T5. Lastly, our results demonstrate the effectiveness of a competitive taper in increasing physiological markers for performance as well as dynamic performance variables. Block periodization training was effective in raising the physical capabilities of an Olympic level 400 m runner which have been shown to directly transfer to sprinting performance.

Suchomel, TJ, Bailey, CA, Sole, CJ, Grazer, JL, and Beckham, GK. Using reactive strength index-modified as an explosive performance measurement tool in Division I athletes. J Strength Cond Res 29(4): 899-904, 2015 - The purposes of this study included examining the reliability of reactive strength index-modified (RSImod), the relationships between RSImod and force-time variables, and the differences in RSImod between male and female collegiate athletes. One hundred six Division I collegiate athletes performed unloaded and loaded countermovement jumps (CMJs). Intraclass correlation coefficients and typical error expressed as a coefficient of variation were used to establish the relative and absolute reliability of RSImod, respectively. Pearson zero-order product-moment correlation coefficients were used to examine the relationships between RSImod and rate of force development, peak force (PF), and peak power (PP) during unloaded and loaded jumping conditions. Finally, independent samples t-tests were used to examine the sex differences in RSImod between male and female athletes. Intraclass correlation coefficient values for RSImod ranged from 0.96 to 0.98, and typical error values ranged from 7.5 to 9.3% during all jumping conditions. Statistically significant correlations existed between RSImod and all force-time variables examined for male and female athletes during both jumping conditions (p ≤ 0.05). Statistically significant differences in RSImod existed between male and female athletes during both unloaded and loaded CMJs (p < 0.001). Reactive strength index-modified seems to be a reliable performance measurement in male and female athletes. Reactive strength index-modified may be described and used as a measure of explosiveness. Stronger relationships between RSImod, PF, and PP existed in female athletes as compared with that in male athletes; however, further evidence investigating these relationships is needed before conclusive statements can be made. Male athletes produced greater RSImod values as compared with that produced by female athletes.

The purpose of this study was to examine the differences in reactive strength index-modified (RSImod), jump height (JH), and time to takeoff (TTT) between 6 U.S. collegiate sport teams. One hundred six male and female Division I collegiate athletes performed unloaded (<1 kg) and loaded (20 kg) countermovement jumps as part of an ongoing athlete monitoring program. Reactive strength index-modified, JH, and TTT values for each team were compared using 1-way analysis of variance. Statistically significant differences in RSImod (p < 0.001), JH (p < 0.001), and TTT (p 0.003) existed between teams during the unloaded jumping condition. Similarly, statistically significant differences in RSImod (p < 0.001), JH (p < 0.001), and TTT (p 0.028) existed between teams during the loaded jumping condition. Men's soccer and baseball produced the greatest RSImod values during both the unloaded and loaded jumping conditions followed by women's volleyball, men's tennis, women's soccer, and women's tennis. The greatest JH during unloaded and loaded jumping conditions was produced by men's baseball followed by men's soccer, women's volleyball, men's tennis, women's soccer, and women's tennis. Men's soccer produced shorter TTT compared with men's baseball (12.7%) and women's soccer (13.3%) during the unloaded and loaded jumping conditions, respectively. Collegiate sport teams exhibit varying reactive strength characteristics during unloaded and loaded jumping conditions. Understanding the differences in RSImod between sports may help direct the creation of training and monitoring programs more effectively for various sports.

Considerable controversy and misguided information has surrounded the inclusion of weightlifting within youth-based strength and conditioning programs to develop strength, power, and speed. This article reviews the evidence to support its inclusion as a safe and effective means to enhance athletic potential. Guidelines are presented to provide coaches with a structured and logical progression model, which is associated with the theoretical concepts underpinning long-term athletic development. It is hoped that this review will serve as a useful tool to help strength and conditioning coaches integrate weightlifting exercises within training programs of young athletes in a safe and effective manner.

The purpose of this study was to examine if short-term periodized programming may improve strength, power, jump kinetics, and sprint efficiency in soccer. Seventeen players (19.6 ± 1.6 yrs; 73.8 ± 8.2 kg; 1.77 ± 0.6 m) were divided into two groups based on mean isometric midthigh pull peak force (IPF) (stronger and weaker) and squat jump (SJ) peak power (PP) (higher power and lower power). Eight weaker players were included in the lower power group, while six stronger players were included in the higher power group. Block periodization was adopted to design strength training consisting of 3-week strength endurance and 4-week maximum strength blocks. Performance data included SJ with polyvinyl chloride pipe (SJ0), 20 kgs bar (SJ20), and 40 kgs (SJ40) bar and 20 m sprint across three time points (baseline: TB; post-block 1: T1; post-block 2: T2 ). Stronger group showed significant increases from TB to T2 in SJ20 peak power (PP), net impulse, and allometrically-scaled PP (p = 0.005 to 0.01, ES = 0.32 to 0.49). Weaker group demonstrated moderate to large increases from TB to T2 in SJ20, allometrically-scaled peak force (PF), PP, and allometrically-scaled PP (p = <0.001 to 0.04, ES = 1.41 to 1.74). Lower power group showed significant increases from TB to T2 in SJ20 allometrically-scaled PF, net impulse, PP, and allometrically-scaled PP (p = <0.001 to 0.026, ES = 1.06 to 2.01). Weaker and less powerful soccer players can benefit from strength-focused training to improve loaded SJ kinetics associating with force production.