Medicine and Health Sciences Commons^™

Evolution Of Smart Devices And Human Movement Apps: Recommendations For Use In Sports Science Education And Practice, Justin Keogh, Hugo Espinosa, Josie Grigg

Justin Keogh

Many smart phones and tablets possess high-speed cameras. An increasing number of human movement professionals (e.g. personal trainers, athletics coaches, strength and conditioning coaches and physiotherapists) are beginning to use human movement analysis apps with their smart phones/tablets to quantitatively assess their clients' performance and injury risk. however, an understanding of the validity and reliability of those tools is required. this narrative review seeks to list some relevant human movement apps; summaries the validity and reliability of selected apps and to provide recommendations for their use in education and practice.

A Comparative Study Of Cervical Hysteresis Characteristics After Various Osteopathic Manipulative Treatment (Omt) Modalities, Precious Barnes, Francisco Laboy, Lauren Noto-Bell, Veronica Ferencz, Jeffrey Nelson, Michael Kuchera

Michael Kuchera

BACKGROUND: Few objective measures have been used to document change in myofascial tissues after OMT.

HYPOTHESIS: Paraspinal tissues associated with cervical somatic dysfunction (SD) will demonstrate quantifiable change in myofascial hysteresis characteristics after a given OMT technique but not after a Sham intervention.

MATERIALS AND METHODS: 240 subjects were palpated for cervical articular SD. A randomly selected intervention (5 OMT techniques or a Sham) was applied to the cervical SD clinically considered to be most severe. A durometer (SA201(®); Sigma Instruments, Cranberry, PA, USA) objectively measured myofascial structures overlying each cervical spinal segment pre- and post- intervention. Using a …

Preliminary Kinematic Gait Analysis Of A Strongman Event: The Farmers Walk., Justin Keogh, Anthony Kattan, Scott Logan, James Bensley, Che Muller, Linda Powell

Justin Keogh

Abstract: This study sought to obtain some preliminary sagittal plane kinematic data on a common strongman event (and conditioning exercise) ‘the farmers walk’ and gain some insight into its kinematic determinants. Five experienced resistance trained males performed three, 20 m farmers walks at maximal speed while carrying 90.5 kg in each hand. Farmers walk average velocity was significantly greater in the middle (8.5–11.5 m) and latter (17–20 m) than initial stage (0–3 m), with this also associated with significant increases in stride length and stride rate and reductions in ground contact time. Comparisons between each subject’s fastest and slowest trials …

Practical Applications Of Biomechanical Principles In Resistance Training: Neuromuscular Factors And Relationships, Jason Lake, Paul A. Swinton, Justin Keogh

Justin Keogh

This paper is the second in our three part series examining how a variety of biomechanical principles and concepts have direct relevance to the prescription of resistance training for the general and athletic populations as well as for musculoskeletal injury rehabilitation. In this paper, we considered different neuromuscular characteristics of resistance exercise. We started by defining the causes of motion, discussing force and Newton’s second law of linear motion. This led to discussion of impulse, and how its relationship with momentum can be used to study force-time curves recorded from different ground-based resistance exercises. This enables the sports biomechanist to …

The Locomotor Kinematics Of Asian And African Elephants: Changes With Speed And Size, John R. Hutchinson, Delf Schwerda, Daniel J. Famini, Robert H.I. Dale, Martin S. Fischer, Rodger Kram

Robert H. I. Dale

For centuries, elephant locomotion has been a contentious and confusing challenge for locomotion scientists to understand, not only because of technical difficulties but also because elephant locomotion is in some ways atypical of more familiar quadrupedal gaits. We analyzed the locomotor kinematics of over 2400 strides from 14 African and 48 Asian elephant individuals (body mass 116-4632 kg) freely moving over ground at a 17-fold range of speeds, from slow walking at 0.40 m s-1 to the fastest reliably recorded speed for elephants, 6.8 m s-1. These data reveal that African and Asian elephants have some subtle differences in how …

The Long-Term Effects Of Water Fluoridation On The Human Skeleton, Debbie Chachra, H. Limeback, T. Willett, Marc Grynpas

Debbie Chachra

Municipal water fluoridation has notably reduced the incidence of dental caries and is widely considered a public health success. However, ingested fluoride is sequestered into bone, as well as teeth, and data on the long-term effect of exposure to these very low doses of fluoride remain inconclusive. Epidemiological studies suggest that effects of fluoride on bone are minimal. We hypothesized that the direct measurement of bone tissue from individuals residing in municipalities with and without fluoridated water would reveal a relationship between fluoride content and structural or mechanical properties of bone. However, consonant with the epidemiological data, only a weak …

A Brief Description Of The Biomechanics And Physiology Of A Strongman Event: The Tire Flip, Justin W.L. Keogh, Amenda L. Payne, Brad B. Anderson, Paul J. Atkins

Justin Keogh

The purpose of this study was to (a) characterize the temporal aspects of a popular strongman event, the tire flip; (b) gain some insight into the temporal factors that could distinguish the slowest and fastest flips; and (c) obtain preliminary data on the physiological stress of this exercise. Five resistance-trained subjects with experience in performing the tire flip gave informed consent to participate in this study. Each subject performed 2 sets of 6 tire flips with a 232-kg tire with 3 minutes of rest between sets. Temporal variables were obtained from video cameras positioned 10 m from the tire, perpendicular …

Living In A Material World: How Visual Cues To Material Properties Affect The Way That We Lift Objects And Perceive Their Weight, Gavin Buckingham, Jonathan Cant, Melvyn Goodale

Gavin Buckingham

The visual properties of an object provide many cues as to the tensile strength, compliance, and density of the material from which it is made. However, it is not well understood how these implicit associations affect our perceptions of these properties and how they determine the initial forces that are applied when an object is picked up. Here we examine the effects of these cues on such forces by using the classic "material-weight illusion" (MWI). Grip and load forces were measured in three experiments as participants lifted cubes made from metal, wood, and expanded polystyrene. These cubes were adjusted to …

Effects Of Estrogen On The Mechanical Behavior Of The Human Achilles Tendon In Vivo, Adam Bryant, Ross Clark, Simon Bartold, Aron Murphy, Kim Bennell, Erik Hohmann, Sonya Marshall-Gradisnik, Craig Payne, Kay Crossley

Sonya Marshall-Gradisnik

The purpose of this study was to elucidate the effect of normal fluctuating [nonmonophasic oral contraceptive pill (MOCP) users] and low, consistent (MOCP users) endogenous plasma estrogen levels on the strain behavior of the Achilles tendon in vivo. Twenty women (age 28.0 ± 4.2 yr, height 1.67 ± 0.07 m, mass 61.6 ± 6.8 kg) who had been using the MOCP for at least 12 mo together with 20 matched women who were non-MOCP users (age 31.9±7.3 yr, height 1.63 ± 0.05 m, mass 62.5 ± 5.9 kg) participated in this study. Non-MOCP users were tested at the time of …