Browsing by Issue Date, starting with "2019"
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- Peak aerobic capacity from incremental shuttle walk test in chronic kidney diseasePublication . Xenophontos, Soteris; Wilkinson, Thomas J.; Gould, Douglas W.; Watson, Emma L.; Viana, João L.; Smith, Alice C.Assessment of cardiorespiratory fitness is an important outcome in chronic kidney disease (CKD). We aimed to develop a predictive equation to estimate peak oxygen uptake (VO2peak ) and power output (WPeak ), as measured during a cardiopulmonary exercise test (CPET), from the distance walked (DW) during the incremental shuttle walk test (ISWT).
- Twelve weeks of supervised exercise improves self-reported symptom burden and fatigue in chronic kidney disease: a secondary analysis of the ‘ExTra CKD’ trialPublication . Wilkinson, Thomas J; Watson, Emma L; Gould, Douglas W; Xenophontos, Soteris; Clarke, Amy L; Vogt, Barbara P; Viana, João L; Smith, Alice CChronic kidney disease (CKD) patients experience a high symptom burden including fatigue, sleep difficulties, muscle weakness and pain. These symptoms reduce levels of physical function (PF) and activity, and contribute to poor health-related quality of life (HRQoL). Despite the gathering evidence of positive physiological changes following exercise in CKD, there is limited evidence on its effect on self-reported symptom burden, fatigue, HRQoL and physical activity.
- Effects of using compound or complex strength-power training during in-season in team sportsPublication . Abade, Eduardo; Sampaio, Jaime; Santos, Luis; Gonçalves, Bruno; Sá, Paulo; Carvalho, Ana; Gouveia, Paulo; Viana, JoãoLiterature is scarce on how players with poorly and well developed physical qualities respond to different combinations of strength-power training during in-season. The aim of this study was to investigate the effects of (i) compound training performed by stronger athletes at different days and (ii) complex training performed by weaker athletes within the same training session. Twenty male handball players were classified as strong or weak according to countermovement jump performance and assigned to a 12-week training programme. Linear sprint, changes of direction, repeated sprint ability and vertical jump capacity were used to assess physical profiles. Compound training performed by stronger players resulted in unclear effects on vertical jump, 20-m and repeated sprint. Likely improvements were found in 10-m sprint (-11.3%; 11.9%). Weaker players who performed complex training presented likely and very likely improvements on vertical jump (13.7%; 5.4%), sprint (10 m, -10.7%; 10.3%; 20 m, -6.0%; 3.4%) and repeated sprint (-4.1%; 3.7%) with moderate to large effect size. The results show that complex and compound strategies are useful in improving the physical profiles of weaker players and maintaining stronger players' capacities during in-season, respectively. Players involved in the same competitive context, even from the same team, may require different strength training strategies.
- Effects of Adding Vertical or Horizontal Force-Vector Exercises to In-season General Strength Training on Jumping and Sprinting Performance of Youth Football PlayersPublication . Abade, Eduardo; Silva, Nuno; Ferreira, Ricardo; Baptista, Jorge; Gonçalves, Bruno; Osório, Sofia; Viana, JoãoAbade, E, Silva, N, Ferreira, R, Baptista, J, Gonçalves, B, Osório, S, and Viana, JL. Effects of adding vertical or horizontal force-vector exercises to in-season general strength training on jumping and sprinting performance of youth football players. J Strength Cond Res XX(X): 000-000, 2019-Football is characterized by short-term high-intensity triaxial activities that require optimized neuromuscular capacity. Thus, training routines must consider the direction of force application, particularly when strength exercises are performed. This study aimed to explore the effects of adding vertical or horizontal force-vector exercises to a 20-week in-season general strength training program on jumping and sprinting performance of youth football players. Twenty-four well-trained male under-17 players participated in this study and were randomly assigned to a control, vertical, or horizontal training group. Control group performed a general strength training program (free weights, eccentric-overload, and body mass exercises) once a week during 20 weeks. Vertical and horizontal groups additionally performed back-half-squat or barbell hip-thrust, respectively. Vertical group improved vertical jump (VJ) (squat jump, likely 4.5; ±4.4% and countermovement jump, likely 4.9; ±4.1%), horizontal jump (HJ) (most likely 7.5; ±2.7%), and sprint (10 m, likely -1.6; ±2.0% and 20 m, very likely -3.3; ±1.6%). The horizontal group showed unclear results in VJ; however, large improvements were observed in HJ (most likely, 13.0; ±4.8%), 10 m and 20 m (very likely -3.0; ±1.8% and most likely -3.8; ±1.0%, respectively). Back-squat and hip-thrust showed an important transference effect to both jumping and sprinting performance. If considering the effects of back-squat on VJ, hip-thrust improved HJ and sprint to a greater extent. This study reinforces the importance of performing both vertical and horizontal force-vector exercises to enhance physical performance during football in-season, even when performed only once a week.
- Coaches’ Emotional Intelligence and Reactive Behaviors in Soccer Matches: Mediating Effects of Coach Efficacy BeliefsPublication . Teques, Pedro; Duarte, Daniel; Viana, JoãoIn the last 10 years, emotional intelligence (EI) has become a current issue of research in psychology, and there are indicators to consider that EI should be analyzed to help the coach to behave effectively during competitions. According to Boardley's (2018) revised model of coaching efficacy, coaches' EI is predictive of their efficacy beliefs, which, in turn, is predictive of coaching behavior. However, little is known about the mediating effects of coaching efficacy dimensions on the relationships between coach's EI and reactive behaviors in competitive settings. Thus, the purpose of this study is to examine mediating effects of coaching efficacy dimensions on the relationship between EI and coaches' reactive behaviors during a game using a multimethod approach. Participants were 258 coaches of youth football players aged 9 to 17 years old. Observations in situ using Coaching Behavior Assessment System (CBAS) were carried on 258 football games during two seasons. At the end of each game, coaches completed the Wong and Law Emotional Intelligence Scale (WLEIS) and the Coaching Efficacy Scale (CES). Structural equation modeling (SEM) analyses revealed that motivation efficacy and character building mediated the relationship between regulation of emotion and positive and negative coaches' reactions during game. Specifically, motivation efficacy mediated the association between regulation of emotion and positive coaches' reactions, and the relationship between regulation of emotion and negative coaches' reactions were mediated by motivation efficacy and character building. In addition, coaching level moderated the relationships between EI, self-efficacy and coaches' reactive behaviors. Findings of the present study showed that coaching efficacy dimensions (i.e., motivation efficacy and character building) that have the capacity to influence their confidence in ability to affect the psychological mood and positive attitude of athletes, transfer the effects of EI (i.e., regulation of emotion) on coaches' verbal reactions during a youth soccer game. Specifically, a coach who feels competent to regulate their own emotions would perceive high beliefs of efficacy to motivate and to build character of their athletes, and this insight has an impact on their positive verbal reactions in response to athletes' performances.
- Sustained exercise programs for hemodialysis patients: The characteristics of successful approaches in Portugal, Canada, Mexico, and GermanyPublication . Viana, João L.; Martins, Pedro; Parker, Kristen; Madero, Magdalena; Pérez Grovas, Héctor; Anding, Kirsten; Degenhardt, Stefan; Gabrys, Iwona; Raugust, Shauna; West, Christina; Cowan, Theresa E.; Wilund, Kenneth R.Despite having good intentions, hemodialysis (HD) clinics often fail to sustain exercise programs that they initiate. There are many reasons for this, including a lack of funding, inadequate training of the clinic staff, a lack of exercise professionals to manage the program or train the staff, and the many challenges inherent to exercising a patient population with multiple comorbid diseases. Despite these barriers, there are several outstanding examples of successful exercise programs in HD clinics throughout the world. The aim of this manuscript is to review the characteristics of four successfully sustained HD exercise programs in Portugal, Canada, Mexico, and Germany. We describe the unique approaches they have used to fund and manage their programs, the varied exercise prescriptions they incorporate, the unique challenges they face, and discuss the benefits they have seen. While the programs differ in many regards, a consistent theme is that they each have substantial and committed support from the entire clinic staff, including the nephrologists, administration, nurses, dietitians, and technicians. This suggests that exercise programs in HD clinics can be successfully implemented and sustained provided significant effort is made to foster a culture of physical activity throughout the clinic.
- Occupational safety and health performance indicators in SMEs: A literature reviewPublication . Barbosa, Catarina; Azevedo, Rui; Rodrigues, Matilde A.Small and medium-sized enterprises (SMEs) face greatest difficulty in managing occupational risks compared to large enterprises. Limited resources, little knowledge about risk management process and deficiencies in organizational processes are often pointed in the literature as important obstacles to occupational safety and health (OSH) performance in SMEs. However, external factors can also be of paramount importance, such as the economic crisis. Because under specific scenarios OSH conditions may deteriorate in SMEs, is important to establish effective indicators.
- Postural Instability During Obstacle Crossing While Performing Manual Material Construction Handling TasksPublication . Azevedo, Rui; Abade, Eduardo; Teixeira, Nuno; Carvalho, Alberto; Sá, Maria Manuel
- Ultrasound assessment of muscle mass in response to exercise training in chronic kidney disease: a comparison with MRIPublication . Gould, Douglas W.; Watson, Emma L.; Wilkinson, Thomas J.; Wormleighton, Joanne; Xenophontos, Soteris; Viana, Joao L.; Smith, Alice C.Chronic kidney disease (CKD) is a catabolic condition associated with muscle wasting and dysfunction, which associates with morbidity and mortality. There is a need for simple techniques capable of monitoring changes in muscle size with disease progression and in response to interventions aiming to increase muscle mass and function. Ultrasound is one such technique; however, it is unknown how well changes in muscle cross-sectional area (CSA) measured using ultrasound relate to changes in whole muscle volume measured using magnetic resonance imaging. We tested whether rectus femoris CSA (RF-CSA) could be used as a valid indication of changes in quadriceps muscle volume as a single measure of muscle size and following a 12 week exercise intervention that resulted in muscle hypertrophy.
- Positional Differences in Peak- and Accumulated- Training Load Relative to Match Load in Elite FootballPublication . Baptista, Ivan; Johansen, Dag; Figueiredo, Pedro; Rebelo, António; Pettersen, Svein A.Quantification of training and match load is an important method to personalize the training stimulus' prescription to players according to their match demands. The present study used time-motion analysis and triaxial-accelerometer to quantify and compare: a) The most demanding passages of play in training sessions and matches (5-min peaks); b) and the accumulated load of typical microcycles and official matches, by playing position. Players performance data in 15 official home matches and 11 in-season microcycles were collected for analysis. Players were divided into four different playing positions: Centre-backs, wing-backs, centre midfielders, and centre forwards. The results show that match demands were overperformed for acceleration counts (acccounts) (131%-166%) and deceleration counts (deccounts) (108%-134%), by all positions. However, relative to match values, training values for sprint distance (sprintdist) and high-intensity run distance (HIRdist) were considerably lower (36%-61% and 57%-71%) than for accelerations and decelerations. The most pronounced difference on the 5-min peaks was observed in sprints (sprintpeak), with wing-backs achieving during the microcycle only 64% of the sprintpeak in matches, while centre backs, centre midfielders, and centre forwards levelled and overperformed the match values (107%, 100%, and 107%, respectively). Differences observed across playing positions in matches and microcycles underline the lack of position specificity of common training drills/sessions adopted by coaches in elite football.