PEAK VERTICAL GROUND REACTION FORCE PREDICTION FROM KINEMATICS IN MALE RUNNERS USING MACHINE LEARNING ALGORITHMS

The purpose of this study was to examine if peak vertical ground reaction forces during treadmill running can be predicted from kinematic input using machine learning models. Eighteen healthy male runners\u27 hip, knee, and ankle sagittal angles, with subject metadata, were input into random forest, support vector, and multi-layer perceptron regressors. Thirty strides per side at three speeds were pulled for the dataset. Random forest performed the best with a correlation coefficient of 0.950 and a root mean squared error of 0.456, while multi-layer perceptron was the worst with values of 0.948 and 0.462 respectively. The study showed machine learning models can predict peak vertical ground reaction forces

DOES A SINGLE PITCHING SESSION INDUCE LOWER EXTREMITY MUSCULAR FATIGUE IN HIGH SCHOOL BASEBALL PITCHERS?

The purpose of this study was to assess hip strength changes and provide a quantifiable measurement to show muscular fatigue after pitching a single pitching session. Fifteen adolescent male baseball pitcher‘s hip external rotator, internal rotator, and extensor strength, along with a functional test were measured before and after a single pitching session. After an average of 19 pitches, all hip strength measures in both legs significantly decreased in post-pitching tests. This study showed pitching increased muscular fatigue of the hip muscles after a small number of pitches thrown. With overall fatigue being a large indicator of injury risk in baseball pitchers, monitoring lower extremity muscular fatigue may be a way to potentially reduce risk of injury

DIFFERENCES IN TEMPORAL VARIABLES AND THEIR EFFECT ON KINETICS IN HIGH SCHOOL PITCHERS WITH HIGH AND LOW PITCH VELOCITIES

The purpose of this study was to compare temporal parameters between high and low velocity high school (HS) pitchers and investigate the influence these parameters have on both pitch speed and upper extremity kinetics. 30 healthy right-handed HS male pitchers with no recent injuries, and clearance to play were included. A 3D motion analysis system was used. Analysis included 15 kinetic and 35 temporal variables. Statistical tests conducted in SPSS. Correlation strength was interpreted as weak, moderate, or strong. High velocity and low velocity throwers showed differences in the timing to progress through the pitching cycle and these temporal variables showed separate relations to pitch speed and kinetics

RUNNING TO THE BEAT: DOES LISTENING TO MUSIC AFFECT RUNNING CADENCE AND LOWER EXTREMITY BIOMECHANICS?

This aimed to determine if music with specific target beats per minute (bpm) could be used for treadmill running cadence training to alter lower extremity biomechanics and, thus, reduce injury risk. Motion analysis and a synchronized triaxial accelerometer collected data from eighteen runners during treadmill running. Participants ran at a self-selected speed (SS) to determine their baseline cadence. They also ran to music where the bpm of the songs was increased by 5% and 10% over SS cadence. Post hoc tests showed significant differences in heart rate from SS. There were no significant differences between cadence or peak acceleration. In the current study, music was not shown to be a viable method for cadence training in runners. Our findings led to methodology recommendations for future work in using music to effectively improve running cadence

COMPARISON OF THROWING ARM MECHANICS DURING LONG-TOSS THROWING AND PITCHING IN PROFESSIONAL BASEBALL PLAYERS

The purpose of this study was to quantify long-toss throwing mechanics of professional baseball pitchers and compare biomechanics of mound pitching to long-toss throwing. Kinematic and kinetic data from 19 professional baseball pitchers throwing from 18-m to 91-m, along with fastball pitches were analyzed using marker-based motion analysis and linear mixed models. Throwing approach and arc were not restricted for long-toss throws. Linear associations were found between the long-toss throwing distances and biomechanical metrics. While elbow and shoulder kinetics increased with distance, they were lower than pitching kinetics at shorter distances and did not significantly exceed the average pitching kinetics at the maximum distance. This is the first study to quantify long-toss throwing mechanics without restriction of throwing style

Relationships between hip flexibility and pitching biomechanics in adolescent baseball pitchers

CONTEXT: Inadequate hip active range of motion (AROM) may stifle the energy flow through the kinematic chain and decrease pitching performance while increasing the risk for pitcher injury. OBJECTIVE: To examine the relationship of hip AROM and pitching biomechanics during a fastball pitch in adolescent baseball pitchers. DESIGN: Cross-Sectional study. SETTING: Biomechanics laboratory. PARTICIPANTS: A voluntary sample of 21 adolescent baseball pitchers (16.1 ± 0.8 yrs.; 183.9 ± 5.2 cm; 77.9 ± 8.3 kg). Main Outcome Measure (s): Bilateral hip internal rotation (IR), external rotation (ER), flexion, extension, and abduction AROM were measured. Three-dimensional biomechanics were assessed as participants threw from an indoor pitching mound to a strike zone net at regulation distance. Pearson correlation coefficients were used to determine correlations between hip AROM and biomechanical metrics. RESULTS: Statistically significant negative correlations were found at foot contact between back hip ER AROM and back hip abduction angle (p=0.030, r=-0.474), back hip ER AROM and torso rotation angle (p=0.032, r=-0.468),and back hip abduction AROM and lead hip abduction angle (p=0.037, r=-0.458). Back hip extension AROM was positively correlated with increased stride length (p=0.043, r=0.446). Lead hip abduction AROM was also positively correlated with normalized elbow varus torque (p=0.034, r=0.464). CONCLUSIONS: There were several relationships between hip AROM and biomechanical variables during the pitching motion. The findings support the influence hip AROM can have on pitching biomechanics. Overall, greater movement at the hips allows for the kinematic chain to work at its maximal efficiency, increasing pitch velocity potential

Relationships Among Shoulder Rotational Strength, Range of Motion, Pitching Kinetics, and Pitch Velocity in Collegiate Baseball Pitchers

Cross, JA, Higgins, AW, Dziuk, CC, Harris, GF, and Raasch, WG. Relationships among shoulder rotational strength, range of motion, pitching kinetics, and pitch velocity in collegiate baseball pitchers. J Strength Cond Res XX(X): 000–000, 2022—Throwing shoulder injuries are the most common type of injury experienced by baseball pitchers. Weakness in the shoulder musculature and insufficient throwing arm range of motion are both risk factors for developing a shoulder injury. The goal of this study was to determine correlations among shoulder rotational strength, range of motion, pitching kinetics, and pitch velocity in collegiate pitchers. Thirteen uninjured male college pitchers were evaluated. Clinical measures included shoulder internal and external rotation range of motion, peak isokinetic internal and external rotator strength, and peak isometric internal and external rotator strength. Three-dimensional biomechanics were assessed as subjects threw from an indoor pitching mound to a strike zone net at regulation distance. Pearson\u27s correlations were used to assess the associations among the clinical measures and throwing metrics. Five significant correlations were found between peak shoulder compressive force and strength, and 4 significant correlations were found between pitching velocity and strength (p \u3c 0.05). No significant correlations were found between range of motion and pitching kinetics or velocity. Our results suggest that as shoulder rotational strength increases, the peak shoulder compressive force and pitch velocity both increase. Knowledge of relationships between strength metrics and pitching biomechanics may allow for improved strength training routines with the goal of increasing velocity without increasing injury risk