Inter-segmental coordination variability during hopping and running on natural and synthetic turf surfaces.

An athlete's performance and musculoskeletal health hinges on their ability to adapt their movements to varying environmental constraints. However, research has yet to offer a thorough understanding of whether coordination variability is altered in response to different synthetic and natural turf surfaces. The purpose of this study was to investigate lower extremity coordination variability during hopping and running on four turf surfaces-three synthetic and one natural.

Video Analysis of Elite American Football Athletes During Vertical Jump.

Introduction: The National Football League (NFL) combine tests the athleticism of prospects competing for the draft. The vertical jump is included to test lower extremity power, yet the components which lead to the greatest performance remain elusive. Therefore, this study aimed to utilize a sample of elite athletes to analyze vertical jump components associated with increased performance and the relationship between vertical jump performance and rookie-year success.

Hip thrust and back squat training elicit similar gluteus muscle hypertrophy and transfer similarly to the deadlift.

We examined how set-volume equated resistance training using either the back squat (SQ) or hip thrust (HT) affected hypertrophy and various strength outcomes. Untrained college-aged participants were randomized into HT (n = 18) or SQ (n = 16) groups. Surface electromyograms (sEMG) from the right gluteus maximus and medius muscles were obtained during the first training session.

Hip thrust and back squat training elicit similar gluteus muscle hypertrophy and transfer similarly to the deadlift.

Purpose: We examined how set-volume equated resistance training using either the back squat (SQ) or hip thrust (HT) affected hypertrophy and various strength outcomes.

Methods: Untrained college-aged participants were randomized into HT or SQ groups. Surface electromyograms (sEMG) from the right gluteus maximus and medius muscles were obtained during the first training session.

Lower-Extremity Motor Synergies in Individuals With and Without Chronic Ankle Instability.

Current theoretical models suggest that ankle sprain copers exhibit movement adaptations contributing to the avoidance of chronic ankle instability. However, few studies have examined adaptations at the level of biomechanical motor synergies. The purpose was to examine characteristics of the support moment synergy between individuals with chronic ankle instability, copers, and healthy individuals.

Ankle Bracing Alters Coordination and Coordination Variability in Individuals With and Without Chronic Ankle Instability.

Context: Ankle bracing is an effective form of injury prophylaxis implemented for individuals with and without chronic ankle instability, yet mechanisms surrounding bracing efficacy remain in question. Ankle bracing has been shown to invoke biomechanical and neuromotor alterations that could influence lower-extremity coordination strategies during locomotion and contribute to bracing efficacy.

Objective: The purpose of this study was to investigate the effects of ankle bracing on lower-extremity coordination and coordination dynamics during walking in healthy individuals, ankle sprain copers, and individuals with chronic ankle instability.

Footwear Alters Lower Extremity Coordination Variability.

Footwear has been shown to have a significant effect on numerous kinematic and kinetic variables during walking and running. While footwear mass is an indisputably important influence on gait patterns, we suspected that the amount of outsole material on most footwear would likely diminish or delay the integration of tactile feedback in motor control strategies during gait. Thus, we designed this study to investigate the influence of footwear and augmented tactile feedback on lower extremity coordination patterns during walking.

Kinetic Analysis of Swimming Flip-Turn Push-Off Techniques.

The aims of the present study were to examine the influences of different push-off techniques on kinetic and kinematic parameters both in and out of the water. The two techniques were: (1) a push off that was characterized by rapid extension of knees and hips towards the wall, prior to contact (i.e.

Local Pressure Application Effects on Neurological and Circulatory Function.

Background: Pain and discomfort reported during sitting is a significant problem for aviators during prolonged missions. Previous work has determined that areas of local pressure exist during prolonged sitting in UH-60 seat systems; however, no work has examined the effects of this local pressure on measures of neurological and circulatory function.

Methods: A total of 30 healthy subjects completed the study in which focal pressure was applied in three conditions (no pressure, pressure to the ischial tuberosity, and pressure to the posterior thigh).

Effects of Game Performance on Softball Pitchers and Catchers.

Oliver, GD, Plummer, HA, Washington, JK, Weimar, WH, and Brambeck, A. Effects of game performance on softball pitchers and catchers. J Strength Cond Res 33(2): 466-473, 2019-The purpose of this study was to examine the effects of game exposure on pitchers and catchers' hip and glenohumeral range of motion (ROM), isometric strength, and vertical jump performance and power.

Local Pressure Application Effects on Discomfort, Temperature, and Limb Oxygenation.

Introduction: Despite significant investment into the development and improvement of military helicopter seat systems, military aviators continue to report seat system related pain and discomfort during prolonged missions.

Methods: Using a factorial repeated measures design, 15 healthy subjects completed the study, in which focal pressure was applied to two locations on the sitting surfaces of the body (ischial tuberosity and middle of the posterior thigh). Pressure was applied using a purpose-built pressure application system allowing subjects to sit in a position mimicking the sitting position in the UH-60 Black Hawk helicopter.

Post-exercise branched chain amino acid supplementation does not affect recovery markers following three consecutive high intensity resistance training bouts compared to carbohydrate supplementation.

Background: Amino acid supplementation has been shown to potentially reduced exercise-induced muscle soreness. Thus, the purpose of this study was to examine if branched chain amino acid and carbohydrate (BCAACHO) versus carbohydrate-only sports drink (CHO) supplementation attenuated markers of muscle damage while preserving performance markers following 3 days of intense weight training.

Methods: Healthy resistance-trained males (n = 30) performed preliminary testing (T1) whereby they: 1) donated a baseline blood draw, 2) performed knee extensor dynamometry to obtain peak quadriceps isometric and isokinetic torque as well as electromyography (EMG) activity at 60°/s and 120°/s, and 3) performed a one repetition maximum (1RM) barbell back squat.

Improving performance by anchoring movement and "nerves".

Golf's governing bodies' recent decision to ban all putting styles "anchoring one end of the club against the body" bridges an important practical problem with psychological theory. We report the first experiment testing whether anchoring provides technical and/or psychological advantage in competitive performance. Many "greats" of professional golf from Arnold Palmer and Jack Nicklaus to Tiger Woods have argued against anchoring, believing that it takes "nerves" out of competitive performance and therefore artificially levels the playing field.

Scapula Kinematics of Youth Baseball Players.

Literature has revealed the importance of quantifying resting scapular posture in overhead athletes as well as quantifying scapular kinematics during dynamic movement. Prior to this project much of the attention in throwing research had been focused on the position of the humerus without description of the positioning of the scapula. Therefore, it was the purpose of this study to present scapular kinematics during pitching in youth baseball players.

Effects of a Simulated Game on Muscle Activation in Youth Baseball Pitchers.

It is generally accepted that playing with fatigue is a primary predictor of injury in youth baseball because muscular fatigue is believed to alter mechanics during the arm cocking and acceleration phases. Therefore, the purpose of this study was to quantitatively describe gluteal and upper extremity muscle activations in youth baseball pitchers during a simulated game. Twenty-three youth baseball players (11.

Biomechanical comparison of frontal plane knee joint moment arms during normal and Tai Chi walking.

[Purpose] Medial knee osteoarthritis, a degenerative joint disease, affects adults. The external knee adduction moment, a surrogate knee-loading measure, has clinical implications for knee osteoarthritis patients. Tai Chi is a promising intervention for pain alleviation in knee osteoarthritis; however, the characteristics of external knee adduction moment during Tai Chi have not been established.

Ex-Vivo Evaluation of a Modified Teno Fix(®) Device Repair Pattern Versus a 3-Loop Pulley for Repair of Equine Flexor Tendons.

Objective: To compare the load to ultimate failure, load to a 2 mm gap, mode of failure, and gap at failure (mm) of the Teno Fix(®) (TF) to the 3-loop pulley (3LP) for repair of equine tendon lacerations. The use of 4TF devices versus 5TF devices on load to ultimate failure and load to a 2 mm gap was also compared.

Study Design: Ex vivo biomechanical study; unbalanced incomplete block (horse) design.

Prolonged restricted sitting effects in UH-60 helicopters.

Introduction: Advances in flight technologies and the demand for long-range flight have increased mission lengths for U.S. Army Black Hawk UH-60 crewmembers.

Gluteus medius and scapula muscle activations in youth baseball pitchers.

The baseball pitching motion is a total kinetic chain activity that must efficiently use both the upper and lower extremity. Of particular importance is the scapular motion, which is critical for humeral positioning and proper alignment of shoulder musculature. It was hypothesized that scapular stability is enhanced by pelvic girdle stability.

Hip range of motion and scapula position in youth baseball pitching pre and post simulated game.

Lower to upper extremity sequencing of energy and force is linked by virtue of the scapula. It was the purpose of this study to examine the relationship between passive hip rotational range of motion and scapular kinematics during baseball pitching. Nineteen youth baseball players (11.

Hip and Shoulder Range of Motion in Youth Baseball Pitchers.

Oliver, GD and Weimar, WH. Hip and shoulder range of motion in youth baseball pitchers. J Strength Cond Res 30(10): 2823-2827, 2016-Lack of range of motion (ROM) has long been suspected as contributing to injury in baseball pitchers.

Balance and exposure to an elevated sloped surface.

Fall injuries and fatalities exceed 50 billion dollars annually. One half of fatal falls are from pitched roof settings. Falls from elevation in an occupational setting have been documented to be a significant issue in today's workforce.

Difference in ratio of evertor to invertor activity between the dominant and nondominant legs during simulated lateral ankle sprain.

Context: The dominant and nondominant legs respond asymmetrically during landing tasks, and this difference may occur during an inversion perturbation and provide insight into the role of ankle-evertor and -invertor muscle activity.

Objective: To determine if there is a difference in the ratio of evertor to invertor activity between the dominant and nondominant legs and outer-sole conditions when the ankle is forced into inversion.

Design: Repeated-measures single-group design.

Arch height index normative values of college-aged women using the arch height index measurement system.

Background: The arch height index measurement system (AHIMS) device has been found to be a reliable and valid instrument for measuring the arch height index (AHI) of the feet of individuals; however, normative data for the AHI are lacking for various populations. Therefore, the purposes of this study were to establish population normative AHI values for college-aged females and to compare the observed AHI data across right and left feet.

Methods: Seventy-nine college-aged females served as study participants, and both feet were measured using the AHIMS in the seated and standing positions.