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Physical Literacy and Human Flourishing

Elizabeth J. Durden-Myers, Margaret E. Whitehead, and Niek Pot

nurturing human flourishing. Therefore, the aim of this paper is to discuss the relationship between physical literacy and human flourishing in detail, unveiling what value this connection may hold in promoting physical literacy as an element integral in achieving a full and flourishing life. Human

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Erratum: Reasons Why Older Adults Engage in Physical Exercise. Comparative Study Eastern Europe Versus Southern Europe

-0450 , an author affiliation was not complete. Pedro Bezerra is also with the Research Center in Sports Sciences, Health Sciences and Human Development, CIDESD, Vila Real, Portugal. The online version of this article has been corrected.

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The Force-Length Curves of the Human Rectus Femoris and Gastrocnemius Muscles in Vivo

Samantha L. Winter and John H. Challis

For a physiologically realistic joint range of motion and therefore range of muscle fiber lengths, only part of the whole muscle force-length curve can be used in vivo; that is, only a section of the force-length curve is expressed. Previous work has determined that the expressed section of the force-length curve for individual muscles can vary between subjects; however, the degree of intersubject variability is different for different muscles. This study determined the expressed section of both the rectus femoris and gastrocnemius—muscles with very different ratios of tendon slack length to muscle fiber optimum length—for 28 nonspecifically trained subjects to test the hypothesis that the value of this ratio affects the amount of variability in the expressed section. The force-length curves of the two muscles were reconstructed from moment-angle data using the method of Herzog & ter Keurs (1988). There was no relationship between the expressed sections of the force-length curve for the two muscles. Less variability was found in the expressed section of the gastrocnemius compared with the rectus femoris, supporting the hypothesis. The lack of relationship between the expressed sections of the two muscles has implications for motor control and for training muscle for rehabilitation.

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New Records in Human Power

Thomas Haugen, Gøran Paulsen, Stephen Seiler, and Øyvind Sandbakk

Higher, faster, stronger: what are the upper limits of human performance? In a published study from January 2008, Berthelot et al 1 estimated that world records had reached 99% of its asymptotic values and that human upper performance limits in sport would be reached within 1 generation. Only

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Subthreshold Vestibular Reflex Effects in Seated Humans Can Contribute to Soleus Activation When Combined With Cutaneous Inputs

Kristen E. Thomas and Leah R. Bent

The integration of vestibular and somatosensory information for the control of lower limb musculature remains elusive. To determine whether a subthreshold vestibular input influences the cutaneous evoked response, the isometric EMG activity in the posturally inactive soleus muscles of 13 healthy, seated subjects was collected. Vestibular afferents were activated using galvanic vestibular stimulation (GVS; 1.8–2.5mA, 500ms), while percutaneous electrical stimulation was delivered to the distal tibial nerve (11ms train of 3 × 1.0 ms pulses, 200Hz) to activate foot sole skin afferents. GVS elicited responses in soleus both independently and when combined with cutaneous stimulation. The responses to the combined sensory input showed an interaction between the two sensory modalities to influence muscle activation. Of note is the presence of significant muscle modulation in the combined condition, where subthreshold vestibular inputs altered the outcome of the cutaneous reflex response. This finding has implications for individuals with sensory deficiency. In the case of an absent or deficient sensory modality, balance protective reflexes to maintain postural equilibrium may be enhanced with targeted sensory augmentation.

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Human Capital Ecosystem Construction in an Emerging Rugby Market

Christopher M. McLeod and Calvin Nite

currently unable to account for markets depending on exceptional human performance, like sport markets. Therefore, a theory is needed that can account for human capital ecosystems . In a human capital ecosystem, actors are responsible for investing in and capturing returns from human capital. The purpose

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Influence of Vestibular Afferent Input on Common Modulation of Human Soleus Motor Units During Standing

Marc Monsour, Tanya D. Ivanova, Tim D. Wilson, and S. Jayne Garland

The purpose of this study was to investigate whether application of bipolar galvanic vestibular stimulation (GVS) would influence the common modulation of motor unit discharge rate in bilateral soleus muscles during quiet standing. Soleus motor unit activity was recorded with fine wire electrodes in each leg. Subjects stood, with eyes closed, on two adjacent force platforms to record postural sway with the head facing straight ahead, turned to right, or turned left. Subjects also swayed voluntarily without GVS to the same position as evoked during the GVS. There was no difference in the common drive to bilateral soleus motoneurons during quiet standing and voluntary sway tasks. Common drive was significantly lower during right cathode GVS with the head straight or turned to the right. These results demonstrate that manipulation of vestibular afferent input influences the common modulation of bilateral soleus motor unit pairs during quiet standing.

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The Human Genome, Physical Activity, Fitness, and Health

Claude Bouchard

of society and even in some corners of the scientific enterprise. But negating or ignoring the underlying biology of human variability does not make it disappear. Human Genomics The exciting field of genomics burst on the scene around 1990 when the Human Genome Project was launched. Spectacular

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Residual Force Enhancement in Humans: A Systematic Review

Neil Chapman, John Whitting, Suzanne Broadbent, Zachary Crowley-McHattan, and Rudi Meir

electrically stimulated in vivo human muscle. 23 However, it is important to note an apparent disparity in magnitude of RFE between electrically stimulated and voluntarily activated contractions. In fact, the magnitude of RFE has been found to vary greatly in vivo voluntarily contracted human muscle. 23

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Fractal Dynamics, Variability, and Coordination in Human Locomotion

Scott W. Ducharme and Richard E.A. van Emmerik

Biological systems are inherently variable, and this variability has been the focus of much research in the movement sciences. In human locomotion research, a commonly accepted convention has been that variability is a one-size-fits-all parameter; more is bad. This “negative” perspective towards