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فهرست مطالب beat knechtle

  • Kamdin Parsakia, Beat Knechtle, Khadijeh Irandoust *

    While it is known that focusing on positive attributes and capabilities can enhance psychological resilience, the specific effectiveness of strength-based therapy in improving self-efficacy and life satisfaction among athletes remains unexplored. By emphasizing positive attributes and capabilities, strength-based therapy aims to enhance athletes' psychological resilience and overall well-being, which are crucial in the highly competitive and physically demanding world of sports. Therefore, this study investigates the effectiveness of strength-based therapy in enhancing the self-efficacy and life satisfaction of athletes. The study used a quasi-experimental design with 50 competitive athletes aged 18-35. The methodology included an 8-week intervention focusing on leveraging individual strengths, goal setting, and resilience building. Outcomes were measured using the General Self-Efficacy Scale and the Satisfaction with Life Scale. To examine these differences, an analysis of variance with repeated measures, coupled with Bonferroni’s post-hoc test, was conducted using SPSS-26. Results indicated significant improvements in both self-efficacy and life satisfaction in the experimental group compared to the control group. The study concludes that strength-based therapy positively impacts athletes' psychological well-being, suggesting its potential for broader application in sports therapy.

    Keywords: Strength-based, Empowering, Athletes, Self-efficacy, Life Satisfaction}
  • Rodrigo Vancini *, Claudio Lira, Beat Knechtle, Katja Weiss, Marilia Andrade
    Background
    Water polo (WP) is a sport with great aerobic/ anaerobic physiological demands. There are few studies that have evaluated the physical demands during the WP game and its relationship with the physiological indices of aerobic fitness
    Aim
    Our aim was to determine the aerobic/ anaerobic profiles of the WP athletes through specific test.
    Materials and Methods
    WP male athletes participated in this study (24.5±5.6 years, 85.9±10.3 kg, 183.0±6.3 cm, n=23). The athletes performed an anaerobic WP test (TAnaWP) to determine the height (Alt- cm) of the 1st/ 15th/ 30th jumps, total time(s) of the jumps (TT30) and the fatigue index (FI). Blood lactate kinetics were determined immediately after (Lac0 min) and during the recovery period; Lac 1/ 3/ 5/ 8/ 12 min. They also performed an aerobic water polo test (TAerWP) to determine maximal oxygen consumption (VO2max) a heart rate (HRmax), peak blood lactate (Lacp) and the second lactate threshold (LL2).
    Results
    The following results (in cm) were obtained in TAnaWP: Alt1st (44±6), Alt15th (32±7) and Alt30th (24±9); TT30 (56.9±9.5); FI (42.0±12.5%); (Lac0), (Lac1), (Lac3), (Lac5), (Lac8) and (Lac12) (5.2±1.7; 7.8±1.6; 9.0±2.0; 9.4±2.2; 9.2±2.7; 8.5±2.2 mmol/L, respectively). The mean maximal values for the aerobic test were: VO2max=44.4±5.3 ml/kg/min, HRmax=174.3±9.1 bpm, Lacp=8.6±2.1 mmol/L. The values obtained at LL2 were: 157.5±13.5 bpm/ 90.5±8.2% HRmax).
    Conclusion
    The proposed tests may be a possibility to determining the physiological fitness of WP athletes.
    Keywords: anaerobic power, lactate threshold, waterpolo, Wingate test}
  • Rodrigo Vancini, Thais Russomano, Marilia S. Andrade, Claudio A. B. de Lira, Beat Knechtle, Juliana S. Herbert

    Gamification i.e., the incorporation of game design elements into non-game contexts, represents a transformative tool in health education. In this sense, the increasingly intertwined fields of technology, education, and health present opportunities for informed decision-making and the training of educators, health professionals, and policymakers. This need to improve teaching and learning methods is particularly evident in the areas of first aid and basic life support (BLS), with the aim of improving clinical results and health outcomes. Our article carried out a narrative review, focusing on the intersection of gamification, technology and first aid/BLS training with the aim of investigating the application of gamification and serious games in emergency medicine with the aim of improving motivation and theoretical and practical skills. of health professionals. In addition, this review emphasizes the role of simulation-based education in first aid skills training, highlighting its contribution to preparing first aiders for real-world scenarios. Ultimately, this review underscores the transformative potential of serious games in medical education, showcasing their effectiveness across diverse contexts. In summary, it enhances comprehension of gamification's role in healthcare and medical education, particularly in first aid training, by underscoring the adaptability and efficacy of serious games in revolutionizing medical and emergency education and healthcare. Nevertheless, it underscores that this remains a relatively underexplored area of knowledge.

    Keywords: Gamification, Education, First aid, Basic life support, BLS, Healthcare}
  • Rizia R. Silva, Cristiellem R. Rufino, Lucas L. Galvão, Rodrigo L. Vancini *, Douglas A. T. Santos, Claudio A. B. de Lira, Marilia S. Andrade, Beat Knechtle, Pantelis T. Nikolaidis, Meiry F. P.Okuno, Rafaela G. dos Santos
    Background

    Intrinsic and extrinsicmotivational factors can affect the levels of adherence of physical activity (PA) during the aging process.

    Objectives

    Investigate the intrinsic and extrinsic aspects and motivation that led older women to enroll in and adhere to a community PA program before the COVID-19 pandemic.

    Methods

    Data were collected via transversal survey before the COVID-19 pandemic. The sample consisted of 21 women, participants of a PA workshop, aged between 60 to 86 years [< 1-year (n = 8) and ≥ 1-year (n = 13) groups]. Motivation was assessed by the Motivation Inventory for Regular Physical Activity Practice (IMPRAF-54), using the 60th percentile to categorize high and low motivation, and two open questions. For qualitative assessment, content analysis was used and the answers were framed into subcategories regarding the motivation factors for adherence and permanence.

    Results

    That adherence to the program was motivated by sociability purposes [total score: 36.0 (6.0), median (interquartile range)] and pleasure [34.0; (6.0)], while the main motivation for permanence was health [40.0 (11.0)]. Differences were noticed between the groups for sociability [38.0 (3.0) P = 0.030] and competitiveness [9.50 (12.0); P = 0.037] highest medians for the < 1 year group. Furthermore, the factors that least motivated older women were competitiveness and aesthetics.

    Conclusions

    Health and sociability were the main motivators for the practice of physical activity among older adult women. Motivation played a fundamental role in the permanence of older adult women in the physical activity program.

    Keywords: Motivation, Older Adults, Aging, Physical Activity, Women}
  • Thais Russomano, Beat Knechtle *, Claudio A. B. de Lira, Marilia S. Andrade, Rodrigo L. Vancini
  • Thais Russomano, Beat Knechtle*, Claudio A. B. de Lira, Marilia S. Andrade, Rodrigo L. Vancini
  • Rizia R. Silva, Cristiellem R. Rufino, Lucas L. Galvão, Rodrigo L. Vancini *, Douglas A. T. Santos, Claudio A. B. de Lira, Marilia S. Andrade, Beat Knechtle, Pantelis T. Nikolaidis, Meiry F. P.Okuno, Rafaela G. dos Santos
    Background

    Intrinsic and extrinsicmotivational factors can affect the levels of adherence of physical activity (PA) during the aging process.

    Objectives

    Investigate the intrinsic and extrinsic aspects and motivation that led older women to enroll in and adhere to a community PA program before the COVID-19 pandemic.

    Methods

    Data were collected via transversal survey before the COVID-19 pandemic. The sample consisted of 21 women, participants of a PA workshop, aged between 60 to 86 years [< 1-year (n = 8) and ≥ 1-year (n = 13) groups]. Motivation was assessed by the Motivation Inventory for Regular Physical Activity Practice (IMPRAF-54), using the 60th percentile to categorize high and low motivation, and two open questions. For qualitative assessment, content analysis was used and the answers were framed into subcategories regarding the motivation factors for adherence and permanence.

    Results

    That adherence to the program was motivated by sociability purposes [total score: 36.0 (6.0), median (interquartile range)] and pleasure [34.0; (6.0)], while the main motivation for permanence was health [40.0 (11.0)]. Differences were noticed between the groups for sociability [38.0 (3.0) P = 0.030] and competitiveness [9.50 (12.0); P = 0.037] highest medians for the < 1 year group. Furthermore, the factors that least motivated older women were competitiveness and aesthetics.

    Conclusions

    Health and sociability were the main motivators for the practice of physical activity among older adult women. Motivation played a fundamental role in the permanence of older adult women in the physical activity program.

    Keywords: Motivation, Older Adults, Aging, Physical Activity, Women}
  • Amine Ghram *, Sirine Abidi, Amal Ben Abdessamie, Katja Weiss, Mohamed Dammak, Salma Jribi, Abdelmoneem Yahia, Sameh Ghroubi, Mohamed Habib Elleuch, Beat Knechtle
    Background

    Vision, vestibular sense, proprioception and muscle strength are required to maintain balance. However, gender could also play a crucial role in postural sway.

    Objectives

    This study was used to examine (i) the impact of gender, surface type, and vision on postural sway; (ii) the effects of gender and vision on the limb symmetry of postural sway; and (iii) to understand the effects of gender, stance, surface type and vision on the alterations of dynamic postural sway alterations.

    Methods

    This was a cross-sectional study in which young, healthy men (n = 15) and women (n = 12) underwent a balance control assessment using a force plate (SATEL, 40 Hz). Postural stances were evaluated in different conditions: opened eyes (EO) and closed eyes (EC), on different surface foam vs. firm, a dominant leg stance (DL) vs. a non-dominant leg stance (NDL), and a mediolateral stance (ML) vs. an anteroposterior stance (AP). The mediolateral sway (ML sway), anteroposterior sway (AP sway), and sway area were calculated from the centre of pressure displacements.

    Results

    ML sway, AP sway and sway area increased when eyes were closed (P < 0.000). Foam surface perturbs balance control more than firm surface under EO and EC conditions for both genders, as observed in the AP sway curve (P < 0.000). A functional symmetry exists between the DL and NDL for all sway parameters: the ML sway, AP sway, and sway area (P = 0.720; P = 0.292; P = 0.954). The AP stance is more stable for the ML sway than the ML stance for both genders (P < 0.001). For the AP sway, the ML stance is more stable than the AP sway AP direction stance for both genders (P < 0.001). Women were significantly more stable than men in the ML stance when vision was absent (P < 0.01).

    Conclusions

    Postural sway was altered more significantly on a foam surface than on a firm surface and symmetry between the DL and NDL was observed. Furthermore, we concluded that women have better dynamic balance control than men.

    Keywords: Gender Differences, Visual Condition, Functional Symmetry, Balance, Posture}
  • Rodrigo Luiz Vancini, Ricardo Borges Viana, Marilia dos Santos Andrade, Claudio Andre Barbosa de Lira, Pantelis Theodoros Nikolaidis, Alexandre Aparecido de Almeida, Beat Knechtle *
    Context

    Physical inactivity levels in the course of the corona virus disease 2019 (COVID-19) outbreak increased significantly. Our aim was to address how the information related to the physical exercise and COVID-19 posted on YouTube reaches the general public during COVID-19 outbreak.

    Evidence Acquisition

    For this, research was carried out crossing the terms covid 19 and physical exercise in the YouTube database. The search was conducted only in the English language and was established/closed on April 26th (2020) to June 26th (2020) in order to observe the dynamics of video production on YouTube.

    Results

    The main terms and concepts mentioned in the analysis of YouTube videos were COVID-19, pandemic, quarantine, social isolation and distance, physical activity, physical exercise, home-based physical exercise, physical inactivity, sedentary lifestyle, and mental health. The information was posted and supported by renowned health and physical exercise experts and entities. The recommendations for physical exercise in the current scenario focused on programs that require little equipment and space (carried out indoors and at home) and at low cost in an attempt to maintain and improve physical and mental health from different population groups.

    Conclusions

    Information about COVID-19 and exercise was growing and progressive throughout the pandemic on YouTube. However, care and guidance are needed in using the information provided by YouTube as a source of reference for the practice of physical exercise during the COVID-19 outbreak.
    Keywords

    Keywords: YouTube, Physical Exercise, SARS-CoV-2, Pandemic, Coronavirus}
  • Amine Ghram *, Sirine Abidi, Amal Ben Abdessamie, Katja Weiss, Mohamed Dammak, Salma Jribi, Abdelmoneem Yahia, Sameh Ghroubi, Mohamed Habib Elleuch, Beat Knechtle
    Background

    Vision, vestibular sense, proprioception and muscle strength are required to maintain balance. However, gender could also play a crucial role in postural sway.

    Objectives

    This study was used to examine (i) the impact of gender, surface type, and vision on postural sway; (ii) the effects of gender and vision on the limb symmetry of postural sway; and (iii) to understand the effects of gender, stance, surface type and vision on the alterations of dynamic postural sway alterations.

    Methods

    This was a cross-sectional study in which young, healthy men (n = 15) and women (n = 12) underwent a balance control assessment using a force plate (SATEL, 40 Hz). Postural stances were evaluated in different conditions: opened eyes (EO) and closed eyes (EC), on different surface foam vs. firm, a dominant leg stance (DL) vs. a non-dominant leg stance (NDL), and a mediolateral stance (ML) vs. an anteroposterior stance (AP). The mediolateral sway (ML sway), anteroposterior sway (AP sway), and sway area were calculated from the centre of pressure displacements.

    Results

    ML sway, AP sway and sway area increased when eyes were closed (P < 0.000). Foam surface perturbs balance control more than firm surface under EO and EC conditions for both genders, as observed in the AP sway curve (P < 0.000). A functional symmetry exists between the DL and NDL for all sway parameters: the ML sway, AP sway, and sway area (P = 0.720; P = 0.292; P = 0.954). The AP stance is more stable for the ML sway than the ML stance for both genders (P < 0.001). For the AP sway, the ML stance is more stable than the AP sway AP direction stance for both genders (P < 0.001). Women were significantly more stable than men in the ML stance when vision was absent (P < 0.01).

    Conclusions

    Postural sway was altered more significantly on a foam surface than on a firm surface and symmetry between the DL and NDL was observed. Furthermore, we concluded that women have better dynamic balance control than men.

    Keywords: Gender Differences, Visual Condition, Functional Symmetry, Balance, Posture}
  • Rodrigo Luiz Vancini, Ricardo Borges Viana, Marilia dos Santos Andrade, Claudio Andre Barbosa de Lira, Pantelis Theodoros Nikolaidis, Alexandre Aparecido de Almeida, Beat Knechtle *
    Context

    Physical inactivity levels in the course of the corona virus disease 2019 (COVID-19) outbreak increased significantly. Our aim was to address how the information related to the physical exercise and COVID-19 posted on YouTube reaches the general public during COVID-19 outbreak.

    Evidence Acquisition

    For this, research was carried out crossing the terms covid 19 and physical exercise in the YouTube database. The search was conducted only in the English language and was established/closed on April 26th (2020) to June 26th (2020) in order to observe the dynamics of video production on YouTube.

    Results

    The main terms and concepts mentioned in the analysis of YouTube videos were COVID-19, pandemic, quarantine, social isolation and distance, physical activity, physical exercise, home-based physical exercise, physical inactivity, sedentary lifestyle, and mental health. The information was posted and supported by renowned health and physical exercise experts and entities. The recommendations for physical exercise in the current scenario focused on programs that require little equipment and space (carried out indoors and at home) and at low cost in an attempt to maintain and improve physical and mental health from different population groups.

    Conclusions

    Information about COVID-19 and exercise was growing and progressive throughout the pandemic on YouTube. However, care and guidance are needed in using the information provided by YouTube as a source of reference for the practice of physical exercise during the COVID-19 outbreak.

    Keywords: YouTube, Physical Exercise, SARS-CoV-2, Pandemic, Coronavirus}
  • Rodrigo Luiz Vancini *, Marilia dos Santos Andrade, Claudio Andre Barbosa de Lira, PantelisTheodoros Nikolaidis, Beat Knechtle
    Context

    The process of decline in endurance capacity is particularly insidious over age 60 and varies considerably with sex, task specificity, and individual training status. Around 50 years of age, aging also implies deterioration of neuromuscular function, affecting muscle strength and power. The aim of the present article was to perform a mini-review to verify how ultra-endurance exercises impact the aging process.

    Evidence Acquisition

    For this, we reviewed the PubMed database (on 20/01/2022) by crossing the key terms, in the simple form, “ultra AND endurance AND exercise AND aging”. This research provided 25 articles from which we made a selection.

    Results

    We observed that the number of articles on the topic is low. The main findings showed that ultra-endurance exercise, high volume physical exercise (six-hours or more) with peak intensity moments, in long-term, is associated with increased risk of heart disease, sudden death, shortening of telomeres, accelerating aging cell, and harm to the healthy aging process and longevity.

    Conclusions

    There is still little literature about the impacts of ultra-endurance practice on the aging process. Although there are indications that this may happen, such as shortening of telomeres and cellular aging, it is still not possible to establish a cause-effect relationship. Furthermore, it is not just about physical exercise, it is necessary to take into account individual factors (intrinsic and extrinsic) that interact with the sports trajectory, life habits, biology, and genetics

    Keywords: Aging, Longevity, Ultra-endurance, Physical exercise, Health}
  • Rodrigo Luiz Vancini *, Marilia dos Santos Andrade, Claudio Andre Barbosa de Lira, Pantelis Theodoros Nikolaidis, Beat Knechtle
    Context

    The process of decline in endurance capacity is particularly insidious over age 60 and varies considerably with sex, task specificity, and individual training status. Around 50 years of age, aging also implies deterioration of neuromuscular function, affecting muscle strength and power. The aim of the present article was to perform a mini-review to verify how ultra-endurance exercises impact the aging process.

    Evidence Acquisition

    For this, we reviewed the PubMed database (on 20/01/2022) by crossing the key terms, in the simple form, “ultra AND endurance AND exercise AND aging”. This research provided 25 articles from which we made a selection.

    Results

    We observed that the number of articles on the topic is low. The main findings showed that ultra-endurance exercise, high volume physical exercise (six-hours or more) with peak intensity moments, in long-term, is associated with increased risk of heart disease, sudden death, shortening of telomeres, accelerating aging cell, and harm to the healthy aging process and longevity.

    Conclusions

    There is still little literature about the impacts of ultra-endurance practice on the aging process. Although there are indications that this may happen, such as shortening of telomeres and cellular aging, it is still not possible to establish a cause-effect relationship. Furthermore, it is not just about physical exercise, it is necessary to take into account individual factors (intrinsic and extrinsic) that interact with the sports trajectory, life habits, biology, and genetics.

    Keywords: Health, Physical exercise, Ultra-endurance, Longevity, Aging}
  • Andre Aschmann, Beat Knechtle *, Vincent Onywera, Pantelis Theodoros Nikolaidis
    Previous research has indicated that sex, age and performance level of finishers influence pacing strategies in the marathon. However, the variation of pacing by country of origin and/or nationality of finishers has not been studied. The aim of this study, therefore, was to examine whether runners with different nationality differ in their pacing strategies. Data (women, n = 117,595; men, n = 180,487) from the ‘New York City Marathon’ between 2006 and 2016 were analysed. A small main effect of nationality on age was shown (P
    Keywords: Age, Running, Performance, Master Athlete, Endurance}
  • Pantelis T. Nikolaidis *, Ilja Kach, Thomas Rosemann, Beat Knechtle
    The aim of the present study was to examine the role of nationality on the pacing of Ironman triathlon (3.8 km swimming, 180 km cycling, and 42.195 km running). Data from 302,535 athletes (women, n = 61,087; men, n = 241,448) competing between 2002 and 2015 in 253 different Ironman triathlon races were analyzed. We examined split times (i.e. swimming, cycling, and running) and transition time, expressed as percentage of the overall race time. Participants were classified into performance groups according to their overall race time: 9 - 10 hours, 10 - 11 hours, 11 - 12 hours, 12 - 13 hours, 13 - 14 hours, 14 - 15 hours, 15 - 16 hours, > 16 hours. Compared to men, women spent relatively less time in swimming (P
    Keywords: Swimming, Cycling, Running, Transition Time, Ultra, Endurance}
  • Pantelis Theodoros Nikolaidis *, Filipe Manuel Clemente, Krzysztof Busko, Beat Knechtle
    Previous research has well described the acute responses of the human body to boxing; nevertheless, less data exist about the effect of recovery modes differing for body position during breaks on these responses. Therefore, the aim of the present study was to examine the impact of two modes of break (sitting versus standing) on heart rate (HR), rate of perceived exertion (RPE), countermovement jump (CMJ) and handgrip muscle strength (HGS) in a simulated boxing combat of three 3-min rounds with 1-min breaks. Participants were male boxers (n = 15) with age, body mass, body height, body mass index and training experience of 21.4 (6.3) yrs, 67.7 (10.0) kg, 172 (6) cm, 22.9 (4.2) kg.m-2 and 2.9 (1.9) yrs, respectively. Mean HR was recorded through all rounds and breaks. Immediately after each round, participants were questioned for RPE (6 - 20 Borg scale). CMJ and HGS were measured before and after combat. A mixed analysis of variance found no time × body position interaction on variables (P > 0.05). However, the p value almost reached statistical significance (P = 0.062, η2 = 0.426) in the case of RPE, that was, compared to the sitting position, a trend of increased RPE for the standing position across time was observed. A main effect of time on HR, RPE and CMJ was shown (P
    Keywords: Countermovement Jump, Handgrip Strength, Heart Rate, match analysis, Rate of Perceived Exertion}
  • Beat Knechtle
    A variety of anthropometric and training characteristics have been identified as predictor variables for race performance in endurance and ultra-endurance athletes. Anthropometric characteristics such as skin-fold thicknesses, body fat, circumferences and length of limbs, body mass, body height, and body mass index were bi-variately related to race performance in endurance athletes such as swimmers in pools and in open water, in road and mountain bike cyclists, and in runners and triathletes over different distances. Additionally, training variables such as volume and speed were also bi-variately associated with race performance. Multi-variate regression analyses including anthropometric and training characteristics reduced the predictor variables mainly to body fat and speed during training units. Further multi-variate regression analyses including additionally the aspects of previous experience such as personal best times showed that mainly previous best time in shorter races were the most important predictors for ultra-endurance race times. Ultra-endurance athletes seemed to prepare differently for their races compared to endurance athletes where ultra-endurance athletes invested more time in training and completed more training kilometers at lower speed compared to endurance athletes. In conclusion, the most important predictor variables for ultra-endurance athletes were a fast personal best time in shorter races, a low body fat and a high speed during training units.
    Keywords: Swimming, Cycling, Running, Skin, Fold, Body Fat, Ultra, Endurance}
  • Miriam Friedrich, Christoph Alexander RÜst, Thomas Rosemann, Patrizia Knechtle, Ursula Barandun, Romuald Lepers, Beat Knechtle
    Purpose
    Lower limb skin-fold thicknesses have been differentially associated with sex in elite runners. Front thigh and medial calf skin-fold appear to be related to 1,500m and 10,000m time in men but 400m time in women. The aim of the present study was to compare anthropometric and training characteristics in recreational female and male half-marathoners.
    Methods
    The association between both anthropometry and training characteristics and race time was investigated in 83 female and 147 male recreational half marathoners using bi- and multi-variate analyses.
    Results
    In men, body fat percentage (β=0.6), running speed during training (β=-3.7), and body mass index (β=1.9) were related to half-marathon race time after multi-variate analysis. After exclusion of body mass index, r2 decreased from 0.51 to 0.49, but body fat percentage (β=0.8) and running speed during training (β=-4.1) remained predictive. In women, body fat percentage (β=0.75) and speed during training (β=-6.5) were related to race time (r2=0.73). For women, the exclusion of body mass index had no consequence on the predictive variables for half-marathon race time.
    Conclusion
    To summarize, in both female and male recreational half-marathoners, both body fat percentage and running speed during training sessions were related to half-marathon race times when corrected with co-variates after multi-variate regression analyses.
    Keywords: Body Fat, Running Speed, Body Mass Index}
  • Martin Bischof, Beat Knechtle, Christoph Alexander RÜst, Patrizia Knechtle, Thomas Rosemann
    Purpose
    The present study investigated the changes in single skinfold thicknesses and body fat during an ultra-endurance cycling race.
    Methods
    One hundred and nineteen ultra-endurance cyclists in the ‘Swiss Cycling Marathon’ covering a distance of 600 km were included. Changes in skinfold thickness, fat mass, skeletal muscle mass and total body water were estimated using anthropometric methods.
    Results
    The subjects were riding at a mean speed of 23.5±4.0 km/h and finished the race within 1,580±296 min. During the race, body mass decreased by 1.5±1.2 kg (P<0.001), and fat mass decreased by 1.5±1.1 kg (P<0.001). Skeletal muscle mass and total body water remained unchanged (P>0.05). The decrease in body mass correlated to the decrease in fat mass (r= 0.20, P=0.03). The skinfold thicknesses at pectoral (-14.7%), abdominal (-14.9%), and thigh (-10.2%) site showed the largest decrease. The decrease in abdominal skinfold was significantly and negatively related to cycling speed during the race (r= -0.31, P<0.001).
    Conclusion
    Cycling 600 km at ~23 km/h led to a decrease in fat mass and in all skinfold thicknesses. The largest decrease in skinfold thickness was recorded for pectoral, abdominal, and thigh site. The decrease in abdominal skinfold thickness was negatively related to cycling speed. The body seems to reduce adipose subcutaneous fat during an ultra-endurance performance at the site of the thickest skinfold.
    Keywords: Endurance, Fat Mass, Muscle Mass, Anthropometry, Body Fat, Training}
  • Beat Knechtle, Christoph Alexander RÜst, Patrizia Knechtle, Thomas Rosemann
    Purpose
    The aim of the present study was to investigate associations between skeletal muscle mass, body fat and training characteristics with running times in master athletes (age > 35 years) in half-marathon, marathon and ultra-marathon.
    Methods
    We compared skeletal muscle mass, body fat and training characteristics in master half-marathoners (n=103), master marathoners (n=91) and master ultra-marathoners (n=155) and investigated associations between body composition and training characteristics with race times using bi- and multi-variate analyses.
    Results
    After multi-variate analysis, body fat was related to half-marathon (ß=0.9, P=0.0003), marathon (ß=2.2, P<0.0001), and ultra-marathon (ß=10.5, P<0.0001) race times. In master half-marathoners (ß=-4.3, P<0.0001) and master marathoners (ß=-11.9, P<0.0001), speed during training was related to race times. In master ultra-marathoners, however, weekly running kilometers (ß=-1.6, P<0.0001) were related to running times.
    Conclusions
    To summarize, body fat and training characteristics, not skeletal muscle mass, were associated with running times in master half-marathoners, master marathoners, and master ultra-marathoners. Master half-marathoners and master marathoners rather rely on a high running speed during training whereas master ultra-marathoners rely on a high running volume during training. The common opinion that skeletal muscle mass affects running performance in master runners needs to be questioned.
    Keywords: Body Fat, Skinfold Thickness, Anthropometry, Running, Sports}
  • Christoph Alexander RÜst, Beat Knechtle, Patrizia Knechtle, Thomas Rosemann, Romuald Lepers
    Purpose
    The aims of the present study were to investigate (i) the changes in participation and performance and (ii) the gender difference in Triple Iron ultra-triathlon (11.4 km swimming, 540 km cycling and 126.6 km running) across years from 1988 to 2011.
    Methods
    For the cross-sectional data analysis, the association between with overall race times and split times was investigated using simple linear regression analyses and analysis of variance. For the longitudinal data analysis, the changes in race times for the five men and women with the highest number of participations were analysed using simple linear regression analyses.
    Results
    During the studied period, the number of finishers were 824 (71.4%) for men and 80 (78.4%) for women. Participation increased for men (r2=0.27, P<0.01) while it remained stable for women (8%). Total race times were 2,146 ± 127.3 min for men and 2,615 ± 327.2 min for women (P<0.001). Total race time decreased for men (r2=0.17; P=0.043), while it increased for women (r2=0.49; P=0.001) across years. The gender difference in overall race time for winners increased from 10% in 1992 to 42% in 2011 (r2=0.63; P<0.001). The longitudinal analysis of the five women and five men with the highest number of participations showed that performance decreased in one female (r2=0.45; P=0.01). The four other women as well as all five men showed no change in overall race times across years.
    Conclusions
    Participation increased and performance improved for male Triple Iron ultra-triathletes while participation remained unchanged and performance decreased for females between 1988 and 2011. The reasons for the increase of the gap between female and male Triple Iron ultra-triathletes need further investigations.
    Keywords: Swimming, Bicycling, Running, Ultra, endurance, Athletic Performance}
  • Wiebke Schmid, Beat Knechtle, Patrizia Knechtle, Ursula Barandun, Christoph Alexander RÜst, Thomas Rosemann, Romuald Lepers
    Purpose
    We intended to determine predictor variables of anthropometry and training for marathon race time in recreational female runners in order to predict marathon race time for future novice female runners.
    Methods
    Anthropometric characteristics such as body mass, body height, body mass index, circumferences of limbs, thicknesses of skin-folds and body fat as well as training variables such as volume and speed in running training were related to marathon race time using bi- and multi-variate analysis in 29 female runners.
    Results
    The marathoners completed the marathon distance within 251 (26) min, running at a speed of 10.2 (1.1) km/h. Body mass (r=0.37), body mass index (r=0.46), the circumferences of thigh (r=0.51) and calf (r=0.41), the skin-fold thicknesses of front thigh (r=0.38) and of medial calf (r=0.40), the sum of eight skin-folds (r=0.44) and body fat percentage (r=0.41) were related to marathon race time. For the variables of training, maximal distance ran per week (r=-0.38), number of running training sessions per week (r=-0.46) and the speed of the training sessions (r=-0.60) were related to marathon race time. In the multi-variate analysis, the circumference of calf (P=0.02) and the speed of the training sessions (P=0.0014) were related to marathon race time. Marathon race time might be partially (r2=0.50) predicted by the following equation: Race time (min)=184.4+5.0 x (circumference calf, cm) –11.9 x (speed in running during training, km/h) for recreational female marathoners.
    Conclusions
    Variables of both anthropometry and training were related to marathon race time in recreational female marathoners and cannot be reduced to one single predictor variable. For practical applications, a low circumference of calf and a high running speed in training are associated with a fast marathon race time in recreational female runners.
    Keywords: Body Fat, Skin, fold, Training, Limb Circumference, Gender, Marathon}
  • Beat Knechtle, Andrea Wirth, Christoph Alexander RÜst, Thomas Rosemann
    Purpose
    The aim of this study was to investigate the relation between anthropometric variables and total race time including split times in 184 recreational male Ironman triathletes.
    Methods
    Body mass, body height, body mass index, lengths and circumferences of limbs, thicknesses of skin-folds, sum of skin-fold thicknesses, and percent body fat were related to total race time including split times using correlation analysis and effect size.
    Results
    A large effect size (r>0.37) was found for the association between body mass index and time in the run split and between both the sum of skin-folds and percent body fat with total race time. A medium effect size (r=0.24-0.36) was observed in the association between body mass and both the split time in running and total race time, between body mass index and total race time, between both the circumference of upper arm and thigh with split time in the run and between both the sum of skin-folds and percent body fat with split times in swimming, cycling and running.
    Conclusions
    The results of this study showed that lower body mass, lower body mass index and lower body fat were associated with both a faster Ironman race and a faster run split; lower circumferences of upper arm and thigh were also related with a faster run split.
  • Beat Knechtle, Patrizia Knechtle, Thomas Rosemann, Romuald Lepers
    Purpose
    The aim of this study was to evaluate predictor variables of race time in female ultra-endurance inliners in the longest inline race in Europe.
    Methods
    We investigated the association between anthropometric and training characteristics and race time for 16 female ultra-endurance inline skaters, at the longest inline marathon in Europe, the ‘Inline One-eleven'' over 111 km in Switzerland, using bi- and multivariate analysis.
    Results
    The mean (SD) race time was 289.7 (54.6) min. The bivariate analysis showed that body height (r=0.61), length of leg (r=0.61), number of weekly inline skating training sessions (r = -0.51) and duration of each training unit (r=0.61) were significantly correlated with race time. Stepwise multiple regressions revealed that body height, duration of each training unit, and age were the best variables to predict race time.
    Conclusion
    Race time in ultra-endurance inline races such as the ‘Inline One-eleven'' over 111 km might be predicted by the following equation (r2 = 0.65): Race time (min) = -691.62 + 521.71 (body height, m) + 0.58 (duration of each training unit, min) + 1.78 (age, yrs) for female ultra-endurance inline skaters.
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