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.

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.

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.

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 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.

Development of a fulcrum methodology to replicate the lateral ankle sprain mechanism and measure dynamic inversion speed.

When the ankle is forced into inversion, the speed at which this movement occurs may affect the extent of injury. The purpose of this investigation was to develop a fulcrum device to mimic the mechanism of a lateral ankle sprain and to determine the reliability and validity of the temporal variables produced by this device. Additionally, this device was used to determine if a single previous lateral ankle sprain or ankle taping effected the time to maximum inversion and/or mean inversion speed.

Effects of previous lateral ankle sprain and taping on the latency of the peroneus longus.

The latency of the peroneus longus may be a key factor in the prevention of lateral ankle sprains (LASs). In addition, ankle taping is often applied to help prevent LASs. The purpose of this study was to determine the effects of a previous LAS and ankle taping on the latency of the peroneus longus after an inversion perturbation.

Footwear and locomotor skill performance in preschoolers.

The effect of footwear on locomotor skill performance was examined. 12 children (4 boys, 8 girls; M age = 56.3 mo.

Difference in response latency of the peroneus longus between the dominant and nondominant legs.

Context: The latency of the peroneus longus in response to an inversion perturbation is a key component in the prevention of lateral ankle sprains. In addition, the dominant ankle is sprained more frequently than the nondominant ankle, but the cause of this has not been examined.

Objective: To investigate the combination of these 2 research-supported statements, the purpose of this study was to use an inversion perturbation that replicates the mechanism of a lateral ankle sprain to determine whether there is a difference in the latency of the peroneus longus between the dominant and nondominant legs.

Impulse-variability theory: implications for ballistic, multijoint motor skill performance.

Impulse-variability theory (R. A. Schmidt, H.

Comparative analysis of human gait while wearing thong-style flip-flops versus sneakers.

Background: Flip-flops are becoming a common footwear option. Casual observation has indicated that individuals wear flip-flops beyond their structural limit and have a different gait while wearing flip-flops versus shoes. This alteration in gait may cause the anecdotal foot and lower-limb discomfort associated with wearing flip-flops.