The Effects of Tempur Insoles on Ground Reaction Forces and Loading Rates in Running

Runners often experience over-use injuries. Ground reaction force (GRFs) patterns have been associated with these over-use injuries; however, it is not solely the magnitude of GRFs, but also the rate at which they are applied that lead to lower extremity injury. Many recreational runners will use over-the-counter insoles as a method of treating or preventing injury. Therefore, the purpose of this study was to examine the efficacy of two insoles on peak GRFs and loading rates. It was hypothesized that no differences in peak GRFs or loading rates would exist with the addition of two insoles during running. Twelve subjects (7 females; 5 males) performed seven running trials in each of the following conditions: no insoles (NORM), over-the-counter insoles (OTC) and memory-foam insoles (TEMPUR). GRFs were recorded using a force plate (1440Hz; AMTI) while subjects ran across a 15 meter lab. A 2 x 3 (gender x insole) repeated measures ANOVA was used to compare the effects of insoles on loading rate and ground reaction forces. Alpha level was set at p \u3c0.05. The current study found no statistical differences in loading rate or GRFs between the insole and no insole conditions. Furthermore, there was no gender effect in any condition. The findings of the current study suggest that insoles do not attenuate shock or decrease loading rate. The lack of shock attenuation associated with insoles suggests they do not protect the lower extremity from injury

The Effects of Insoles on Loading Rate in Level Running

Introduction: Running is one of the most popular recreational sports in America with over 250 million regular runners. Recreational and competitive runners often experience over-use injuries including plantar fasciitis, Achilles tendinitis and stress fractures. Previous research has shown that the transmission of ground reaction force through the lower extremity leads to these over-use injuries; however, it is not solely the magnitude of vertical ground reaction forces, but also the rate at which these forces are applied that may lead to lower extremity injury. Many recreational runners will use over-the-counter insoles as a method of treating an injury or as a way of prolonging or renewing and old pair of running shoes. Therefore, the purpose of this study was to examine the efficacy of two insoles on peak vertical ground reaction forces and loading rates. It was hypothesized that no differences in peak vertical ground reaction forces or loading rates would exist with the addition of two insoles during running. Methods: Twelve subjects (7 females; 5 males) performed seven trials in each of the following conditions: no insoles, over-the-counter insoles and custom made memory-foam insoles. Over-the-counter insoles were made by Dr. Scholl’s while the memory-foam insoles were made of tempur-pedic material. Ground reaction forces were recorded using a force plate (1440Hz; AMTI) while subjects ran across a 15 meter lab. Loading rate was calculated as the quotient of the peak vertical ground reaction force during load response and the time from heel strike to peak vertical ground reaction force in load response. A 2 x 3 (gender x insole) repeated measures ANOVA was used to compare the effects of insoles on loading rate. Alpha level was set at p \u3c0.05. Results: The current study found no statistical differences in normalized or non-normalized loading rate between the insole and no insole conditions. Furthermore, there was no effect of gender on loading rate. Discussion and Conclusions: The findings of the current study suggest that insoles do not attenuate shock or decrease loading rate. The lack of shock attenuation associated with the insoles suggests they are not effective in prolonging the life of a pair of running shoes by improving shock absorption. Furthermore, these data suggest that insoles will not aid in the prevention or treatment of injury in running

Lower Extremity Kinetics in High and Low-Arched Athletes during Landing

Abnormal foot function has been associated with an increased rate of injury in the athletic population. It has been shown that high-arched (HA) and low-arched (LA) athletes experience different injury patterns. These may be the manifestation of different loading and joint torque patterns in HA and LA athletes. It has been shown that HA and LA athletes have unique kinematic and kinetic patterns during running. However, little research has examined ground reaction forces (GRF) and lower extremity joint kinetics in HA and LA athletes during landing tasks. PURPOSE: To examine GRF and knee and ankle joint torques in HA and LA athletes during a landing task. METHODS: Ten HA (age: 20.8±2.5 years; height: 1.62±0.07 m; mass: 58.3±5.4 kg; arch index: 0.386±0.010) and 10 LA (age: 21.1±2.3; height: 1.63±0.07m; mass: 58.9±10.9kg; arch index: 0.259±0.043) female recreational athletes participated in this study. Each subject performed five barefooted drop landing trials from a height of 30 cm. GRFs and three-dimensional (3D) kinematics were recorded simultaneously using a force plate (1200 Hz, AMTI) and 7-camera motion analysis system (240 Hz, Vicon). GRFs and joint torques were calculated using Visual 3D (C-Motion, Inc.) and critical events were determined using custom software. A one-way ANOVA was used to compare group differences with an alpha level of p\u3c0.05. RESULTS: The GRF profiles were similar between the HA and LA athletes. However, HA athletes exhibited a mean eversion moment compared to an inversion moment in LA athletes (HA: -0.05±0.08 Nm/kg; LA: 0.04±0.07 Nm/kg). Additionally, the HA athletes generated greater peak knee external rotation torques (HA: 0.18±0.06 Nm/kg; LA: 0.26±0.08 Nm/kg) compared to LA athletes during the landing task. Knee extension and abduction torques were similar between the two groups in contrast to previous findings. CONCLUSIONS: The greater mean eversion torques exhibited by the HA athletes may be a response to being more inverted throughout the landing task. Increased eccentric contraction of the ankle everters would control eversion during landing. Similarly, the increased knee external rotation torques would act to limit knee internal rotation during landing. These altered kinetic patterns may increase the risk of injury within these groups of athletes

A Comparison of Three Computer-based Methods Used to Determine EMG Signal Amplitude

Electromyography is a commonly used method to determine relative effort and neuromuscular drive to skeletal muscle. A limitation of the interpretation of EMG within the literature is the many methods used to determine the intensity of muscle activation. In the current study, ten healthy young adults performed a level walking task while EMG was recorded from the tibialis anterior, medial gastrocnemius and fibularis longus. The EMG data were rectified and smoothed using the root mean squared (RMS). Peak RMS (pRMS), mean RMS (mRMS) and integrated EMG (iEMG) were normalized to the peak value within the subject and were used to determine EMG amplitude. A 3x3 repeated measures analysis of variance was used to determine significant differences between the methods of determining EMG amplitude. The findings of the current study show that pRMS produced significantly lower EMG amplitudes than mRMS or iEMG values. Furthermore, mRMS and iEMG produced nearly identical normalized EMG amplitudes. Based on the findings of this study and the components of each measurement of EMG amplitude, it is suggested to use mRMS to determine EMG amplitude

Changes in brain activity in response to problem solving during the abstinence from online game play

Background and aims: Several studies have suggested that addictive disorders including substance abuse and pathologic gambling might be associated with dysfunction on working memory and prefrontal activity. We hypothesized that excessive online game playing is associated with deficits in prefrontal cortex function and that recovery from excessive online game playing might improve prefrontal cortical activation in response to working memory stimulation. Methods: Thirteen adolescents with excessive online game playing (AEOP) and ten healthy adolescents (HC) agreed to participate in this study. The severity of online game play and playing time were evaluated for a baseline measurement and again following four weeks of treatment. Brain activation in response to working memory tasks (simple and complex calculations) at baseline and subsequent measurements was assessed using BOLD functional magnetic resonance imaging (fMRI). Results: Compared to the HC subjects, the AEOP participants exhibited significantly greater activity in the right middle occipital gyrus, left cerebellum posterior lobe, left premotor cortex and left middle temporal gyrus in response to working memory tasks during baseline measurements. After four weeks of treatment, the AEOP subjects showed increased activity within the right dorsolateral prefrontal cortex and left occipital fusiform gyrus. After four weeks of treatment, changes in the severity of online game playing were negatively correlated with changes in the mean β value of the right dorsolateral prefrontal cortex in response to complex stimulation. Conclusions: We suggest that the effects of online game addiction on working memory may be similar to those observed in patients with substance dependence

High Force Unimanual Handgrip Contractions Increase Ipsilateral Sensorimotor Activation and Functional Connectivity

Imaging and brain stimulation studies seem to correct the classical understanding of how brain networks, rather than contralateral focal areas, control the generation of unimanual voluntary force. However, the scaling and hemispheric-specificity of network activation remain less understood. Using fMRI, we examined the effects of parametrically increasing right-handgrip force on activation and functional connectivity among the sensorimotor network bilaterally with 25%, 50%, and 75% maximal voluntary contractions (MVC). High force (75% MVC) unimanual handgrip contractions resulted in greater ipsilateral motor activation and functional connectivity with the contralateral hemisphere compared to a low force 25% MVC condition. The ipsilateral motor cortex activation and network strength correlated with relative handgrip force (% MVC). Increases in unimanual handgrip force resulted in greater ipsilateral sensorimotor activation and greater functional connectivity between hemispheres within the sensorimotor network. (C) 2020 IBRO. Published by Elsevier Ltd. All rights reserved

A cohort study of patients seeking Internet gaming disorder treatment

Background and aims: Although Internet gaming disorder (IGD) is included as a condition in the fifth edition of Diagnostic and Statistical Manual of Mental Disorders, little is known about its nature or treatment response. This study is a follow-up of 755 patients who received professional treatment for IGD over a 5-year period. Methods: The initial recommended treatment course lasted for 8 weeks, with additional care provided as needed. Treatment completion rates in the complete sample, as well as baseline predictors of treatment completion and long-term recovery among the 367 patients who completed the follow-up, are reported. Results: Nearly two thirds of patients who initiated treatment for IGD completed the 8-week psychotherapy. Of these, about two thirds who had not recovered completely by the end were offered additional care. Independent predictors of extended treatment were higher baseline scores on the Young Internet Addiction Scale, Beck Depression Inventory (BDI), and Korean-Attention Deficit Hyperactivity Disorder-Rating Scale (K-ADHD-RS). Between 1 and 5 years later, 33.5% of the complete sample was considered as recovered from IGD. Significant predictors of recovery from IGD were older age, earlier admission to the clinic, lower baseline scores on the BDI and K-ADHD-RS, and no offer of extended treatment. Discussion and conclusions: The majority of the patients seeking treatment for IGD continued experiencing difficulties and randomized controlled trials of interventions, which are needed to be conducted to improve outcomes. Age, family, social factors, and psychological symptoms should be considered, while designing and evaluating interventions, because they impact initial and sustained response to treatment for IGD

Comparison of brain connectivity between Internet gambling disorder and Internet gaming disorder: A preliminary study

Background and aims Given the similarities in clinical symptoms, Internet gaming disorder (IGD) is thought to be diagnostically similar to Internet-based gambling disorder (ibGD). However, cognitive enhancement and educational use of Internet gaming suggest that the two disorders derive from different neurobiological mechanisms. The goal of this study was to compare subjects with ibGD to those with IGD. Methods Fifteen patients with IGD, 14 patients with ibGD, and 15 healthy control subjects were included in this study. Resting-state functional magnetic resonance imaging data for all participants were acquired using a 3.0 Tesla MRI scanner (Philips, Eindhoven, The Netherlands). Seed-based analyses, the three brain networks of default mode, cognitive control, and reward circuitry, were performed. Results Both IGD and ibGD groups demonstrated decreased functional connectivity (FC) within the default-mode network (DMN) (family-wise error p  Discussion and conclusions The IGD and ibGD groups shared the characteristic of decreased FC in the DMN. However, the IGD group demonstrated increased FC within the cognitive network compared with both ibGD and healthy comparison groups