• Added mass in human swimmers: age and gender differences 

      Caspersen, Cecilie; Berthelsen, Petter A.; Eik, Mari; Pâkozdi, Csaba; Kjendlie, Per-Ludvik (Journal article; Peer reviewed, 2010-05-23)
      In unstationary swimming (changing velocity), some of the water around the swimmer is set in motion. This can be thought of as an added mass (Ma) of water. The purpose of this study was to find added mass on human swimmers ...
    • Breaststroke swimmers moderate internal work increases toward the highest stroke frequencies 

      Lauer, Jessy; Olstad, Bjørn Harald; Minetti, Alberto Enrico; Kjendlie, Per-Ludvik; Rouard, Annie Hélène (Journal article; Peer reviewed, 2015-09-18)
      A model to predict the mechanical internal work of breaststroke swimming was designed. It allowed us to explore the frequency–internal work relationship in aquatic locomotion. Its accuracy was checked against internal work ...
    • Can you swim in waves? Children´s swimming, floating and entry skills in calm and simulated unsteady water conditions 

      Kjendlie, Per-Ludvik; Pedersen, Tommy; Thoresen, Trine; Setlo, Trond; Moran, Kevin; Stallman, Robert Kieg (Journal article; Peer reviewed, 2013)
      Little is known about the transfer of swimming skills from indoor, flat, calm conditions to outdoor, wavy, unsteady conditions. The aim of the current study was to examine the differences in swimming, floating, and entry ...
    • Can you swim?: an exploration of measuring real and perceived water competency 

      Moran, Kevin; Stallman, Robert Keig; Kjendlie, Per-Ludvik; Dahl, Dagmar; Blitvich, Jennifer; Petrass, Lauren A.; McElroy, G. Keith; Goya, Toshiaki; Teramoto, Keisuke; Matsui, Atsunori; Shimongata, Shuji (Journal article; Peer reviewed, 2012)
      Little is known about the relationship between real and perceived water competence among youth in the context of drowning prevention or of their perceptions of their risk of drowning. This study reports the findings of ...
    • Combined strength and endurance training in competitive swimmers 

      Aspenes, Stian; Kjendlie, Per-Ludvik; Hoff, Jan; Helgerud, Jan (Peer reviewed; Journal article, 2009-09-01)
      A combined intervention of strength and endurance training is common practice in elite swimming training, but the scientific evidence is scarce. The influences between strength and endurance training have been investigated ...
    • Critical evaluation of oxygen-uptake assessment in swimming 

      Sousa, Ana; Figueiredo, Pedro; Pendergast, David; Kjendlie, Per-Ludvik; Vilas-Boas, João P.; Fernandes, Ricardo J. (Journal article; Peer reviewed, 2014-03)
      Swimming has become an important area of sport science research since the 1970s, with the bioenergetic factors assuming a fundamental performance-influencing role. The purpose of this study was to conduct a critical ...
    • Drag characteristics of competitive swimming children and adults 

      Kjendlie, Per-Ludvik; Stallman, Robert Keig (Peer reviewed; Journal article, 2008-02)
      The aims of this study were to compare drag in swimming children and adults, quantify technique using the technique drag index (TDI), and use the Froude number (Fr) to study whether children or adults reach hull speed at ...
    • High intensity interval training improves VO2peak, maximal lactate production, time trial and competition performance in 9-11 year old swimmers 

      Sperlich, Billy; Zinner, Christoph; Helleman, Ilka; Kjendlie, Per-Ludvik; Holmberg, H. C.; Mester, Joachim (Journal article; Peer reviewed, 2010-08-04)
      Training volume in swimming is usually very high when compared to the relatively short competition time. High-intensity interval training (HIIT) has been demonstrated to improve performance in a relatively short training ...
    • Movement patterns in free water play after swimming lessons with flotation aids 

      Kjendlie, Per-Ludvik; Mendritzki, Marcel (Journal article; Peer reviewed, 2012)
      The aim of this study was to investigate the movement patterns of children during free play in a swimming school setting. It was hypothesized that children being taught using flotation vests would be less likely to surface ...
    • Muscle activation in world champions, world-class and national breaststroke swimmers 

      Olstad, Bjørn Harald; Zinner, Christoph; Vaz, João Rocha; Cabri, Jan; Kjendlie, Per-Ludvik (Journal article; Peer reviewed, 2016-08)
      Purpose: Investigating the muscle activation patterns and coactivation with the support of kinematics in some of the world’s best breaststrokers and identify performance discriminates related to national elites at maximal ...
    • Muscle coordination during breaststroke swimming: comparison between elite swimmers and beginners 

      Vaz, João R.; Olstad, Bjørn Harald; Cabri, Jan; Kjendlie, Per-Ludvik; Pezarat-Correia, Pedro; Hug, Francois (Journal article; Peer reviewed, 2016-02)
      The present study aimed to compare muscle coordination strategies of the upper and lower limb muscles between beginners and elite breaststroke swimmers. Surface electromyography (EMG) of eight muscles was recorded in 16 ...
    • Muscle coordination, activation and kinematics of world-class and elite breaststroke swimmers during submaximal and maximal efforts 

      Olstad, Bjørn Harald; Vaz, Joao Rocha; Zinner, Christoph; Cabri, Jan; Kjendlie, Per-Ludvik (Journal article; Peer reviewed, 2016-07-25)
      The aims of this study were to describe muscular activation patterns and kinematic variables during the complete stroke cycle (SC) and the different phases of breaststroke swimming at submaximal and maximal efforts. Surface ...
    • Physical fitness and psychological hardiness as predictors of parasympathetic control in response to stress: a Norwegian police simulator training study 

      Sandvik, Asle Makoto; Gjevestad, Espen Svendsen; Aabrekk, Einar; Öman, Peter H.; Kjendlie, Per-Ludvik; Hystad, Sigurd William; Bartone, Paul T.; Hansen, Anita Lill; Johnsen, Bjørn Helge (Peer reviewed; Journal article, 2019)
      The individual biopsychological response to a specific stressor is the result of a complex interplay between many different factors including physiology, behavior, and personality. The goal of the present study was to ...
    • A proposed framework for developing a plan for research in lifesaving and water safety 

      Stallman, Robert Keig; Kjendlie, Per-Ludvik (Peer reviewed; Journal article, 2008-02)
      In the centers for aquatic research, the infrastructure, methodology, and expertise already exist. What remains is to integrate the needs and interests of lifesaving research into these programs. Especially in physiology ...
    • Swimming propulsion forces are enhanced by a small finger spread 

      Marinho, Daniel A.; Barbosa, Tiago; Reis, Victor M.; Kjendlie, Per-Ludvik; Alves, Francisco B.; Vilas-Boas, João P.; Machado, Leandro; Silva, António J.; Rouboa, Abel I. (Journal article; Peer reviewed, 2010-02)
      The main aim of this study was to investigate the effect of finger spread on the propulsive force production in swimming using computational fluid dynamics. Computer tomography scans of an Olympic swimmer hand were ...