Evaluating Postural Transition Movement Performance in Individuals with Essential Tremor via the Instrumented Timed Up and Go.

Flexibility in performing various movements like standing, walking, and turning is crucial for navigating dynamic environments in daily life. Individuals with essential tremor often experience movement difficulties that can affect these postural transitions, limiting mobility and independence. Yet, little research has examined the performance of postural transitions in people with essential tremor. Therefore, we assessed postural transition performance using two versions of the timed up and go test: the standard version and a more complex water-carry version. We examined the total duration of the standard and water-carry timed up and go in 15 people with and 15 people without essential tremor. We also compared the time taken for each phase (sit-to-stand phase, straight-line walk phase, stand-to-sit phase) and the turning velocity between groups. Our findings revealed decreased performance across all phases of standard and water-carry timed up and go assessments. Further, both ET and non-ET groups exhibited reduced performance during the water-carry timed up and go compared to the standard timed up and go. Evaluating specific phases of the timed up and go offers valuable insights into functional movement performance in essential tremor, permitting more tailored therapeutic interventions to improve functional performance during activities of daily living.

Usage and acceptability of data normalization in baseball pitching.

In baseball pitching biomechanics, kinetic values are commonly ratio 'normalised' by dividing by mass or mass*height to allow for comparison between athletes of different sizes. However, creating a normalised ratio variable should meet certain statistical assumptions. Our purpose was to determine if elbow valgus torque predicted by pitching velocity is influenced by normalisation using regression model comparison with and without normalised torque values. Motion capture data for youth to professional pitchers (n = 1988) were retrospectively analysed. Normalisation assumptions were tested by comparing linear regression models to analogous models with an intercept fixed at zero and by examining remaining correlations between the confounding variable and new, normalised variable. Both mass (p < 0.001) and mass*height (p < 0.001) normalisation did not remove their respective relationship with torque. After accounting for mass or mass and height, velocity predicted 10% of variance in elbow valgus torque, whereas velocity predicted 59% of mass normalised torque and 45% of mass*height normalised torque. Ratio normalisation does not fully account for anthropometric variables that differ across pitchers and leads to different conclusions in the magnitude of velocity's predictive effect on elbow valgus torque. Therefore, we recommend using regression model comparison to account for anthropometric variables in baseball pitching kinetic data.

The relationship between gait speed and mediolateral stability depends on a person's preferred speed.

Mediolateral stability during walking requires active control and is complex. Step width, a proxy for stability, follows a curvilinear relationship as gait speeds increase. However, despite the complexity of maintenance for stability, no study has yet investigated the variation across individuals of the relationship between speed and step width. The purpose of this study was to determine if variation between adults affects the estimation of the relationship between speed and step width. Participants walked on a pressurized walkway 72 times. Gait speed and step width were measured within each trial. Mixed effects models assessed the relationship between gait speed and step width, and the variability in the relationship across participants. The relationship between speed and step width followed a reverse J-curve on average, but the relationship was moderated by participants' preferred speed. Step width response as speed increases is not homogenous in adults. This finding suggests that "appropriate" stability moderation (tested across a range of speeds) differs as a function of an individual's preferred speed. Mediolateral stability is complex, and further research to elucidate individual factors contributing to variation is needed.

Core and Whole-Body Vibration Exercise Improve Military Foot March Performance in Novice Trainees: A Randomized Controlled Trial.

INTRODUCTION: The purpose of the present study was to investigate core exercise training and whole-body vibration (WBV) as a training method to improve performance and recovery from an 8-km military foot march in novice trainees. MATERIALS AND METHODS: A 3 × 5 repeated measures randomized control trial was used to evaluate the effects of core exercise training and WBV on performance and recovery from an 8-km foot march. Thirty-nine participants were randomized into three groups: core exercise (Ex), WBV with core exercise (WBVEx), and control. Each participant completed two 8-km foot marches (FM1 and FM2) with a 35 pound rucksack, separated by 4 weeks. Participants in the Ex and WBVEx groups completed 3 weeks of core exercise training, three times per week in between FM1 and FM2. Performance time, creatine kinase (CK), and interleukin-6 (IL-6) were measured. The Auburn University Institutional Review Board approved all aspects of this study (protocol number: 19-211 MR 1907). RESULTS: Performance time (P < .001) and CK (P = .005) were significantly improved during FM2 as compared to FM1. The Ex (d = -0.295) and WBVEx (d = -0.645) treatments had a large effect on performance time. CK (P < .001) and IL-6 (P < .001) were significantly elevated at the completion of the foot march regardless of group. Only CK remained elevated for 2 days (P < .001) following the foot march. CONCLUSIONS: Core exercise training with or without WBV improved 8-km foot march performance time by 5-6 minutes. The improvements are likely because of an increase in trunk stability. Additionally, this study showed that completing two identical foot marches a month apart increases performance and improves recovery.

Sleep restriction impairs visually and memory-guided force control.

Sleep loss is a common phenomenon with consequences to physical and mental health. While the effects of sleep restriction on working memory are well documented, it is unknown how sleep restriction affects continuous force control. The purpose of this study was to determine the effects of sleep restriction on visually and memory-guided force production magnitude and variability. We hypothesized that both visually and memory-guided force production would be impaired after sleep restriction. Fourteen men participated in an eleven-day inpatient sleep study and completed a grip force task after two nights of ten hours' time in bed (baseline); four nights of five hours' time in bed (sleep restriction); and one night of ten hours' time in bed (recovery). The force task entailed four 20-second trials of isometric force production with the thumb and index finger targeting 25% of the participant's maximum voluntary contraction. During visually guided trials, participants had continuous visual feedback of their force production. During memory-guided trials, visual feedback was removed for the last 12 seconds of each trial. During both conditions, participants were told to maintain the target force production. After sleep restriction, participants decreased the magnitude of visually guided, but not memory-guided, force production, suggesting that visual attention tasks are more affected by sleep loss than memory-guided tasks. Participants who reported feeling more alert after sleep restriction and recovery sleep produced higher force during memory-guided, but not visually guided, force production, suggesting that the perception of decreased alertness may lead to more attention to the task during memory-guided visual tasks.

Words matter: instructions dictate "self-selected" walking speed in young adults.

BACKGROUND: Variability in gait speed is influenced by age and health status. However, no study has investigated the effects of different instructions on gait speed. RESEARCH QUESTION: This study investigated how walking prompts contributed to variability in gait speed. METHODS: Participants walked on a pressurized walkway. Gait speed variability was assessed using multilevel modeling. RESULTS: 61% of the variance in gait speed was due to instruction, while 14% was due to individual differences. SIGNIFICANCE: Reference values for gait speed across a number of prompts will be highly useful for assessing gait performance in young adults. Further, the instruction given produces a large amount of variability in selected walking speed. This finding urges researchers to maintain consistency when delivering walking instructions.

A Dietary Intervention High in Green Leafy Vegetables Reduces Oxidative DNA Damage in Adults at Increased Risk of Colorectal Cancer: Biological Outcomes of the Randomized Controlled Meat and Three Greens (M3G) Feasibility Trial.

Green leafy vegetables (GLV) may reduce the risk of red meat (RM)-induced colonic DNA damage and colorectal cancer (CRC). We previously reported the primary outcomes (feasibility) of a 12-week randomized controlled crossover trial in adults with habitual high RM and low GLV intake with body mass index (BMI) > 30 kg/m2 (NCT03582306). Herein, our objective was to report a priori secondary outcomes. Participants were recruited and enrolled in 2018, stratified by gender, and randomized to two arms: immediate intervention group (IG, n = 26) or delayed intervention group (DG, n = 24). During the 4 week intervention period, participants were provided with frozen GLV and counseled to consume 1 cooked cup equivalent daily. Participants consumed their normal diet for the remaining 8 weeks. At each of four study visits, anthropometrics, stool, and blood were taken. Overall, plasma Vitamin K1 (0.50 ± 1.18 ng/mL, p < 0.001) increased, while circulating 8OHdG (-8.52 ± 19.05 ng/mL, p < 0.001), fecal 8OHdG (-6.78 ± 34.86 ng/mL, p < 0.001), and TNFα (-16.95 ± 60.82 pg/mL, p < 0.001) decreased during the GLV intervention compared to control periods. Alpha diversity of fecal microbiota and relative abundance of major taxa did not differ systematically across study periods. Further investigation of the effects of increased GLV intake on CRC risk is warranted.

The Association of Upper-Body Kinematics and Earned Run Average of National Collegiate Athletic Association Division I Softball Pitchers.

ABSTRACT: Friesen, KB, Barfield, JW, Murrah, WM, Dugas, JR, Andrews, JR, and Oliver, GD. The association of upper-body kinematics and earned run average of national collegiate athletic association Division I softball pitchers. J Strength Cond Res 35(11): 3145-3150, 2021-Although recent literature has increased examination of the association of injury and biomechanics, there remains a lack of evidence supporting optimal windmill pitch mechanics. Therefore, the purpose of this study was to investigate trunk and pitching arm kinematics and their association with performance outcome: earned run average (ERA), in collegiate softball pitchers. Twenty-three NCAA Division I collegiate softball pitchers (20.14 ± 1.07 years; 173.93 ± 6.68 cm; and 85.79 ± 11.06 kg) performed 3 maximal effort rise ball pitches to a catcher located at a distance of 43 ft. (13.11 m). Kinematic data of the trunk and pitching arm were collected using an electromagnetic tracking system. A multiple regression analysis was performed at each pitch event: top of backswing, foot contact, ball release, and follow-through. The multiple regression at foot contact showed an overall statistically significant regression equation (F6, 16 = 3.7, p = 0.017) and explained approximately 42% of the variance in ERA (R = 0.579, Adj. R2 = 0.421). Results revealed that those pitchers who had greater trunk (SE = 0.018, t = -2.5, p = 0.023) and elbow flexion (SE = 0.006, t = -4.2, p = 0.001) at the event of foot contact had lower ERAs. This study supported previous research on the importance of trunk and elbow angle at front foot contact on rise ball pitch performance. These key technique points and the importance of elbow flexors should be explored in future research and potentially visually attended to by coaches and strength professionals.

Compound Bias due to Measurement Error When Comparing Regression Coefficients.

Multiple regression is often used to compare the importance of two or more predictors. When the predictors being compared are measured with error, the estimated coefficients can be biased and Type I error rates can be inflated. This study explores the impact of measurement error on comparing predictors when one is measured with error, followed by a simulation study to help quantify the bias and Type I error rates for common research situations. Two methods used to adjust for measurement error are demonstrated using a real data example. This study adds to the literature documenting the impact of measurement error on regression modeling, identifying issues particular to the use of multiple regression for comparing predictors, and offers recommendations for researchers conducting such studies.

Primary Outcomes of a Randomized Controlled Crossover Trial to Explore the Effects of a High Chlorophyll Dietary Intervention to Reduce Colon Cancer Risk in Adults: The Meat and Three Greens (M3G) Feasibility Trial.

Preclinical and observational research suggests green leafy vegetables (GLVs) may reduce the risk of red meat (RM)-induced colonic DNA damage and colon cancer (CC). We sought to determine the feasibility of a high GLV dietary intervention in adults with an increased risk of CC (NCT03582306) via a 12-week randomized controlled crossover trial. Participants were randomized to immediate or delayed (post-4-week washout) intervention groups. During the 4-week intervention period, participants were given frozen GLVs and counseled to consume one cooked cup equivalent daily. The primary outcomes were: accrual-recruiting 50 adults in 9 months; retention-retaining 80% of participants at completion; and adherence-meeting GLV intake goals on 90% of days. Adherence data were collected twice weekly and 24-h dietary recalls at each time point provided nutrient and food group measures. The Food Acceptability Questionnaire (FAQ) was completed to determine acceptability. On each of the four study visits, anthropometrics, stool, saliva, and blood were obtained. Fifty adults were recruited in 44 days. Participants were 48 ± 13 years of age, 62% female, and 80% Caucasian, with an average BMI at screening of 35.9 ± 5.1. Forty-eight (96%) participants were retained and completed the study. During the intervention phase, participants consumed GLVs on 88.8% of days; the adherence goal of one cup was met on 73.2% of days. Dietary recall-derived Vitamin K and GLVs significantly increased for all participants during the intervention periods. Overall satisfaction did not differ between intervention and control periods (p = 0.214). This feasibility trial achieved accrual, retention and acceptability goals, but fell slightly short of the benchmark for adherence. The analysis of biological specimens will determine the effects of GLVs on gut microbiota, oxidative DNA damage, and inflammatory cytokines.

A Rasch Analysis of the KeyMath-3 Diagnostic Assessment.

Effectively assessing children's academic development can help school professionals make placement decisions and prepare appropriate instructional supports. The KeyMath-3 Diagnostic Assessment (Connolly, 2008) is a widely used assessment of children's mathematical abilities; however, despite much use, the measurement properties of the KeyMath-3 DA have not been examined, aside from the development and standardization phases. The current study conducted a Rasch analysis of the Basic Concepts content area of the KeyMath-3 DA in a diverse sample of 308 young children to assess the quality of the assessment. Rasch analytic procedures examined unidimensionality, item and person fit statistics, reliability, and item hierarchy. Misfitting items were further examined, and response patterns were modified. In general, results show that the Basic Concepts subscale is a good measure of the underlying construct of young children's understanding of the basic concepts in mathematics. Implications are discussed.

Fine motor skills and executive function both contribute to kindergarten achievement.

This study examined the contribution of executive function (EF) and multiple aspects of fine motor skills to achievement on 6 standardized assessments in a sample of middle-socioeconomic status kindergarteners. Three- and 4-year-olds' (n=213) fine and gross motor skills were assessed in a home visit before kindergarten, EF was measured at fall of kindergarten, and Woodcock-Johnson III Tests of Academic Achievement were administered at fall and spring. Correlations indicated that EF and fine motor skills appeared distinct. Further, controlling for background variables, higher levels of both EF and fine motor skills, specifically design copy, predicted higher achievement on multiple subtests at kindergarten entry, as well as improvement from fall to spring. Implications for research on school readiness are discussed.

Fine motor skills and early comprehension of the world: two new school readiness indicators.

Duncan et al. (2007) presented a new methodology for identifying kindergarten readiness factors and quantifying their importance by determining which of children's developing skills measured around kindergarten entrance would predict later reading and math achievement. This article extends Duncan et al.'s work to identify kindergarten readiness factors with 6 longitudinal data sets. Their results identified kindergarten math and reading readiness and attention as the primary long-term predictors but found no effects from social skills or internalizing and externalizing behavior. We incorporated motor skills measures from 3 of the data sets and found that fine motor skills are an additional strong predictor of later achievement. Using one of the data sets, we also predicted later science scores and incorporated an additional early test of general knowledge of the social and physical world as a predictor. We found that the test of general knowledge was by far the strongest predictor of science and reading and also contributed significantly to predicting later math, making the content of this test another important kindergarten readiness indicator. Together, attention, fine motor skills, and general knowledge are much stronger overall predictors of later math, reading, and science scores than early math and reading scores alone.