Classifying batted ball outcomes from Division I collegiate baseball players.

Modern technology challenges anecdotal beliefs on baseball performance. The study's purpose examines these beliefs by classifying batted ball outcomes. Three categories of independent variables (anthropometry, in-game situation, technique-based), from 1,922 batted ball outcomes produced by 230 players, were used to classify the likelihood of hits during 2021 college baseball games. Anthropometry included player's heights and weights. In-game situation entailed batter side, same side, ahead count, and pitch type. Technique-based variables measured by TrackMan radar included exit speed (ExSp), launch angle (LA), batted ball distance (BBD), and hang time (HT). Binary logistic regression analysis was performed with batted ball outcome as the dependent variable. Independent variables provided a good fit (χ2 (10) = 522.358, p < 0.01) and correctly classified nearly three-fourths of outcomes. Height (ß = 0.030, p < 0.05), ExSp (ß = 0.023, p < 0.05), LA (ß = 0.028, p < 0.01), and BBD (ß = 0.067, p < 0.01) each had significant positive associations, yet HT (ß = -1.661, p < 0.01) had a significant negative association, with batted ball outcomes. TrackMan provided four significant independent variables. Anthropometry's contribution to batting outcome was modest, while in-game situation's impact was non-significant; results contradict anecdotal beliefs of their importance.

Palm cooling temperatures on thermal, physiological, perceptual, and ergogenic indices from rowing workouts in a thermoneutral environment.

Gel pack temperatures were compared for responses to thermal, physiological, perceptual, and ergogenic indices from healthy women (n = 12) and men (n = 8). They did three rowing workouts to identify an ideal temperature. In a randomised sequence, and as subjects wore gloves equipped with mesh pouches during workouts, gel packs at one of the three average temperatures (10.6, 12.6, or 14.9°C) were inserted into the pouches. Data were collected before, during and after multi-stage workouts. Thermal, physiological, and perceptual data were each compared with three-factor (condition, gender, time) mixed effect model ANCOVAs, with repeated measures for condition and time, and gender as a between subjects' factor. Distance rowed was assessed with two-factor (condition, gender) mixed effect model ANCOVAs, with repeated measures for condition, and gender as a between subjects' factor. Within-subject contrasts was the post-hoc, and α = 0.05 denoted significance. Despite small differences for distance rowed, many dependent variables had significant inter-condition effects, whereby 10.6°C gel packs had the best thermal and physiological responses. The 10.6°C temperature 1): likely removed the most body heat, perhaps through cold-induced vasodilation and, 2): may be optimal, as it evoked the best thermal and physiological responses.

Intermittent Palm Cooling's Impact on Resistive Exercise Performance.

To examine palm cooling's (15 °C) impact, subjects performed 3 four-set leg press workouts in a randomized sequence. Per workout they received 1 of 3 treatments: no palm cooling, palm cooling between sets, or palm cooling between sets and post-exercise. Dependent variables were examined with three-way ANOVAs; average power underwent a three-way ANCOVA with body fat percentage as the covariate. Simple effects analysis was our post hoc and α=0.05. Left hand skin temperatures produced a two-way interaction (no palm cooling, palm cooling between sets>palm cooling between sets and post-exercise at several time points). A "high responder" subset had their data analyzed with an additional three-way ANOVA that again produced a two-way interaction (palm cooling between sets>no palm cooling>palm cooling between sets and post-exercise at multiple time points). Blood lactate results included a two-way interaction (no palm cooling>palm cooling between sets, palm cooling between sets and post-exercise at 0 min post-exercise). Average power yielded a two-way interaction (palm cooling between sets, palm cooling between sets>no palm cooling for the fourth set). Intermittent palm cooling hastened heat removal and blood lactate clearance, as well as delayed average power decrements.

The magnitude of blood lactate increases from high speed workouts.

To examine blood lactate concentrations from high-speed exercise resistive exercise, subjects performed workouts on an inertial kinetic exercise (Oconomowoc, WI) device. Workouts entailed two 60-s sets of elbow flexor (curling) repetitions. Pre- and post-exercise blood lactate concentrations were measured, via a fingertip blood drop, with an analyzer. From workouts the average acceleration, maximum force and total torque were derived. Blood lactate concentrations were analyzed with a 2 (gender)×2 (time) ANOVA, with repeated measures for time. Average acceleration, maximum force and total torque were analyzed with one-way (gender) ANOVAs. With an α=0.05, blood lactate concentrations had a time (prewomen) effects. Current blood lactate concentrations were commensurate with other studies that used a modest level of resistance and engaged a small muscle mass. Given the current workout protocol and muscle mass engaged, as well as parallels to other results, our study appears to offer a valid portrayal of subsequent changes in blood lactate concentrations from high-speed resistive exercise.

Anthropometry as a predictor of high speed performance.

To assess anthropometry as a predictor of high-speed performance, subjects performed four seated knee- and hip-extension workouts with their left leg on an inertial exercise trainer (Impulse Technologies, Newnan GA). Workouts, done exclusively in either the tonic or phasic contractile mode, entailed two one-minute sets separated by a 90-second rest period and yielded three performance variables: peak force, average force and work. Subjects provided the following anthropometric data: height, weight, body mass index, as well as total, upper and lower left leg lengths. Via multiple regression, anthropometry attempted to predict the variance per performance variable. Anthropometry explained a modest (R2=0.27-0.43) yet significant degree of variance from inertial exercise trainer workouts. Anthropometry was a better predictor of peak force variance from phasic workouts, while it accounted for a significant degree of average force and work variance solely from tonic workouts. Future research should identify variables that account for the unexplained variance from high-speed exercise performance.

An isokinetic investigation of contractile mode's effect on the elbow flexors.

Healthy, sedentary, college-age subjects (n = 16) performed concentric or eccentric maximal unilateral isokinetic (1.08 rad s(-1)) elbow flexor contractions (4 sets of 12 repetitions) to fatigue as physiological data were concurrently collected. Net caloric expenditure was determined using indirect calorimetry, whereas the electromyogram examined root mean square (RMS) and mean power frequency (MPF) values for the biceps brachii, brachioradialis, and palmaris longus. Eccentric exercise resulted in significantly greater (p < 0.05) absolute (total work per kilocalorie) and relative (total work per kilocalorie per kilogram) exercise efficiency values. Concentric biceps brachii and brachioradialis RMS values were significantly (p < 0.05) greater than corresponding eccentric values, suggesting greater motor unit recruitment. Concentric MPF values, a measure of motor unit fatigue, showed significantly (p < 0.05) greater before and after decrements following exercise for the biceps brachii and brachioradialis. Greater exercise efficiency with less motor unit recruitment and fatigue results from eccentric exercise.

Resistance exercise countermeasures for space flight: implications of training specificity.

While resistance exercise should be a logical choice for prevention of strength loss during unloading, the principle of training specificity cannot be overlooked. Our purpose was to explore training specificity in describing the effect of our constant load exercise countermeasure on isokinetic strength performance. Twelve healthy men (mean +/- SD: 28.0 +/- 5.2 years, 179.4 +/- 3.9 cm, 77.5 +/- 13.6 kg) were randomly assigned to no exercise or resistance exercise (REX) during 14 days of bed rest. REX performed five sets of leg press exercise to volitional fatigue (6-10 repetitions) every other day. Unilateral isokinetic concentric-eccentric knee extension testing performed before and on day 15 prior to reambulation included torque-velocity and power-velocity relationships at four velocities (0.52, 1.75, 2.97, and 4.19 rad s-1), torque-position relationship, and contractile work capacity (10 repetitions at 1.05 rad s-1). Two (group) x 2 (time) ANOVA revealed no group x time interactions; thus, groups were combined. Across velocities, angle-specific torque fell 18% and average power fell 20% (p < 0.05). No velocity x time or mode (concentric/eccentric) x time interactions were noted. Torque x position decreased on average 24% (p < 0.05). Total contractile work dropped 27% (p < 0.05). Results indicate bed rest induces rapid and marked reductions in strength and our constant load resistance training protocol did not prevent isokinetic strength losses. Differences between closed-chain training and open-chain testing may explain the lack of protection.

Deoxyribonucleic acid profiling by restriction fragment length polymorphism analysis--a compilation of validation studies.

In preparation for the application of restriction fragment length polymorphism (RFLP) analysis methods to casework, validation studies were performed at the Indianapolis-Marion County Forensic Services Agency (IMCFSA). They encompassed the following areas: standard specimens, sample consistency, reproducibility, mixed specimens, environmental insults, minimum sample requirements, non-probative casework, repetitive sizing accuracy, precision and match criteria analysis, and population studies including K562 data analysis. All studies yielded results as expected, were consistent with those previously reported by other laboratories, and formed a strong foundation on which to base future casework analysis.

The effects of albuterol and isokinetic exercise on the quadriceps muscle group.

Subjects performed 9 wk of isokinetic knee extensions twice weekly. Albuterol (N = 13) or placebo (N = 9) was administered for 6 wk; groups received 16 mg.d-1 of either treatment. Training consisted of three sets of 10 repetitions at 45 degrees.s-1. Data were collected at weeks 0, 6, and 9. Concentric and eccentric variables examined included: peak torque (CPT, EPT), total work (CTW, ETW), average power (CAP, EAP), time to peak torque (CTTPT, ETTPT), peak torque to body weight ratio (CPT/BW), and work to body weight ratio (CW/BW, EW/BW). Other variables included: thigh circumference (CIRC), thigh cross-sectional area (CSA), forced vital capacity (FVC), and forced expiratory volume (FEV1), MANOVA and the Dunn-Bonferroni post-hoc found differences within groups for CPT, CTW, CAP, CPR/BW, EPT, ETTPT, and CSA. Interactions were noted for CW/BW, ETW, EAP, EPT/BW, and ETW/BW; with persons administered albuterol yielding superior values. CW/BW, ETW, and EAP showed interactions at post-testing, while EPT/BW and EW/BW interacted at both midtesting and post-testing. Results indicate therapeutic doses of albuterol administered with resistance exercise may augment strength gains.

Restriction fragment length polymorphism (RFLP) typing of DNA extracted from nasal secretions.

The restriction fragment length polymorphism (RFLP) analysis of blood, semen, and other body fluids, has become increasingly important in violent criminal cases. The identification of additional tissues suitable for comparison with suspected donors has obvious potential benefit. One type of tissue, that found in nasal secretions, has previously received little attention with regards to genetic analysis. We collected blood and nasal secretion samples from eight individuals, subjected them to traditional RFLP typing methods, and analyzed the results using probes for loci D2S44, D1S7, D10S28, D4S139, and D17S79. All nasal samples provided high DNA yields and hybridization results that matched the corresponding blood standards. Thus, nasal secretions are shown to have potentially significant evidentiary value.

Increased muscle strength in paralyzed patients after spinal cord injury: effect of beta-2 adrenergic agonist.

The administration of beta-2 adrenergic agonists in experimental animals result in an increased strength of skeletal muscle. In this study, we evaluated whether a beta-2 adrenergic agonist, metaproterenol, had an effect on muscle size and strength in a group of patients with muscular atrophy following spinal cord injury. Ten male subjects were randomly divided into 2 groups and agreed to participate in a prospective, double-blind, placebo-controlled, and crossover study. Metaproterenol (80 mg/day), or placebo, was administered orally for a period of 4 weeks. Muscle strength was measured by a force transducer interfaced with a microcomputer. Muscle size was calculated and expressed as a cross-sectional area of upper arm and forearm using a formula. Metaproterenol induced a significant increase of muscle strength in both groups of subjects, compared with placebo (p < .001). Similarly, there was an increase in a muscle size in the forearm following the administration of metaproterenol. Our data indicate that beta-2 adrenergic agonists may improve both muscle strength and size in patients with muscular atrophy following spinal cord paralysis.