The Science of Softball

Effects of a Simulated Game and Doubleheader Inning on Peak Kinetics in Softball Pitching Across Pitch Types

BACKGROUND

Softball pitchers frequently pitch at high volumes. Previous research has demonstrated changes in mechanics, range of motion, and perceived levels of fatigue and pain at high workloads. To date, little research has assessed changes in kinetics at high workloads across pitch types to understand the injury risk.

PURPOSE

To examine changes in peak kinetics of the shoulder, elbow, and wrist of the pitching arm throughout a simulated game and doubleheader inning.

STUDY DESIGN

Descriptive laboratory study.

METHODS

A total of 19 high school softball pitchers (mean age, 15.1 ± 1.5 years; mean height, 1.6 ± 0.2 m; mean weight, 76.3 ± 16.9 kg) participated. Pitchers threw 4 innings of 25 randomly assigned pitches to mimic a game's high pitch count. Participants then rested for 30 minutes before subsequently proceeding to pitch the first inning of a doubleheader. Each pitcher threw a fastball, drop ball, curveball, and changeup. Peak shoulder, elbow, and wrist kinetics were compared across the first, last, and doubleheader innings and pitch types.

RESULTS

Compared with the first inning, significant decreases in kinetics were observed at the shoulder, elbow, and wrist in the last (P < .016) and doubleheader (P < .016) innings, particularly for shoulder and elbow compression force during the drop ball and curveball pitch types and wrist net force for all pitch types but the changeup. Significant decreases in elbow and wrist kinetics were observed during the changeup between the last and doubleheader innings (P < .016). Furthermore, differences in kinetics were observed between pitch types (P < .008); notably, the changeup had reduced kinetics compared with the fastball and breaking ball pitch types (drop ball, curveball) across innings.

CONCLUSION

Across innings, attenuations in select joint kinetics of the pitching arm occurred that were specific to the pitch type. Across pitch types, peak kinetics was often greater during the fastball, while the changeup displayed the lowest peak kinetics.

CLINICAL RELEVANCE

The joints examined in this study are common sites of overuse injuries in pitchers. This work adds to previous findings on decrements in neuromuscular function as well as self-reported fatigue and pain with tournament-style pitching that may increase the injury risk. Collectively, these findings support developing a protocol combining functional testing and player-reported outcomes to aid sports specialists' decisions for pitchers to continue to pitch or return to play, which may help prevent musculoskeletal injuries and time loss from sports participation.

Shoulder Injury Incidence and Epidemiology in Youth, High School, and Collegiate Fastpitch Softball Players: A Systematic Review and Future Research Perspectives

CONTEXT

Fastpitch softball is one of the most popular sports in the United States among young female athletes. Softball players regularly subject their shoulders to extreme range of motion and high velocity movements. To date, no systematic review has reported on the epidemiology and incidence of shoulder injuries in softball players.

OBJECTIVE

To describe the incidence and epidemiology of softball-related shoulder injuries in youth, high school, and collegiate female softball players.

DATA SOURCES

PubMed, Web of Science, and Embase were searched for relevant English language articles from 1980 to 2023.

STUDY SELECTION

Studies selected based on predefined inclusion criteria. Studies were required to be available full text, in English.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 4.

DATA EXTRACTION

A preliminary screening was performed based on study title and abstract. In the subsequent screening, the full text versions of the remaining articles were evaluated by 2 reviewers for the fulfillment of the inclusion criteria.

RESULTS

A total of 7 articles met criteria for inclusion. All studies evaluated injuries among softball players for at least 1 season. In total, there were 1107 softball-related shoulder injuries reported in the 7 studies included in this systematic review. Of the 3 studies that included a shoulder injury rate, a mean rate of 4.01 shoulder injuries per 10,000 athlete-exposures was calculated. The 2 most common shoulder injuries were shoulder muscle-tendon strains (297) and shoulder/biceps tendinitis (220).

CONCLUSION

High-level prospective studies reporting injury incidence and risk factors among female softball players are extremely limited. Only 2 studies eligible for inclusion in this systematic review were prospective in nature, with neither of these reporting the specific injury rate for shoulder injuries among softball players.

Interpersonal coordination analysis in bat-and-ball sports under a real game situation: Asymmetric interaction and delayed coupling

This study investigated the interpersonal coordination between the pitcher and the batter in bat-and-ball sports. Although the importance of interpersonal coordination is widely accepted in many sports, no studies have investigated it in bat-and-ball sports because the dominant task constraints surrounding the interaction between pitcher and batter make it difficult to apply conventional analytic techniques. To address the issue, this study proposes a new analytical framework to investigate interpersonal coordination in bat-and-ball sports under a real game situation with two main characteristics: asymmetric interaction and delayed coupling. First, the dynamic time warping technique was used to evaluate the stability of the head movement pattern of the pitcher and batter, and cross-correlation analysis was used to quantify the temporal relationship between them. We found that the head movement pattern of batters was significantly more unstable than that of pitchers, and approximately 60% of the variance of the change in the head movement pattern of batters could be explained by that of the pitchers. Moreover, expert batters followed a pitcher's movements with a specific time delay of approximately 250 ms. These findings highlight the characteristics of interpersonal coordination in bat-and-ball sports: the pitcher can make a pre-patterned stable motion, whereas the batter needs to follow and adjust their movement to it. Although the effects of prediction ability need to be investigated to understand its detailed mechanism, the contribution of this study is that it revealed the existence of the interpersonal coordination between the pitcher and batter of bat-and-ball sports under a real game situation.

Advancements for the Future: A National Survey of Fastpitch Softball Coaches' Perspectives on Injury Prevention Programming

Background

Approximately 50 percent of softball injuries are the result of overuse or chronic conditions. However, research exploring preventative measures for softball players is limited and usage of injury prevention strategies among softball coaches is unknown.

Hypothesis/Purpose

This survey aimed to investigate if softball coaches are implementing injury prevention programs to reduce injury and improve the performance of their players. The secondary purpose was to identify barriers to the implementation of injury prevention programs. Finally, this survey explored the coaches' knowledge of injury risk factors and their views on design and usage of preventative programs.

Study Design

Descriptive cross-sectional survey.

Methods

A 35-item survey was sent to approximately 14,000 high school and collegiate fastpitch softball coaches throughout the United States. Data were collected over a three-month period with an overall response rate of 1.2%.

Results

Among responding coaches, 45.9% (n=79/172) reported implementing injury prevention programs. Coaches who implement injury prevention strategies most frequently utilize team-based programs (68.8%, n=52/93) compared to group-based (19.0%, n=15/93) or individualized programs (15.2%, n=12/93). Coaches who do not use preventative programming reported that being unsure of what program to perform (53.8%, n=50/93) and not having enough staff (20.4%, n=19/93) were the greatest barriers to implementation. Although over 50% of coaches recognized arm fatigue/overuse (27.9%, n=48/172) and decreased core strength (22.7%, n=39/172) were important risk factors, 36% (n=94/172) "disagree" that softball pitchers should adhere to pitch counts and 90% (n=83/92) believe that preventative programming for pitchers and position players should be similar.

Conclusion

Less than 50 percent of softball coaches implement exercise programs to prevent injury. Limited familiarity with effective program design, inadequate staffing, and inconsistent risk factor awareness are the major contributors to lacking implementation. Collaboration between rehabilitation professionals and softball coaches regarding preventative programming should be considered.

Level of Evidence

Level 3©The Author(s).

Epidemiology of Pediatric Baseball and Softball Player Injuries

Background:

Baseball and softball are popular sports in the United States and are responsible for a large number of youth sports injuries each year.

Purpose:

To investigate recent differences in youth baseball and softball injuries evaluated in nationwide emergency departments.

Study Design:

Descriptive epidemiology study.

Methods:

The National Electronic Injury Surveillance System (NEISS) database was examined for softball and baseball injuries in pediatric patients (age, 7-21 years) from 2010 through 2019. Patients were classified as children (age, 7-13 years), adolescents (age, 14-18 years), or young adults (age, 19-21 years). Case narratives were used to categorize injuries as contact injuries (hit by bat or ball), field injuries (sliding into base, collision with another player, catching, or running), throwing injuries, or other.

Results:

An unweighted total of 24,717 baseball injuries and 13,162 softball injuries were recorded. A nationwide estimate of 861,456 baseball injuries and 511,117 softball injuries were sustained during the studied time period, with estimated respective injury rates of 86,146 and 51,112 per year. Injured softball players were most commonly adolescent (47%) and female (92%), while injured baseball players were most commonly children (54%) and male (90%). There was a greater proportion of baseball-related injuries involving the head/neck (41%) as compared with softball-related injuries (30%) (P < .01). Conversely, a greater proportion of softball-related injuries involved the lower extremity (32%) as compared with baseball-related injuries (19%) (P < .01). When comparing diagnosis, softball injuries were more often sprains/strains (28%) than baseball injuries (18%) (P < .01). When comparing mechanisms of injury, baseball athletes were more likely to be evaluated with contact injuries than were softball athletes (49% vs 40%, P < .01).

Conclusion:

Youth baseball athletes were more likely to be injured through contact mechanisms and had a higher proportion of injuries related to the head/neck/face, whereas softball injuries more frequently involved the lower extremity and resulted in a sprain/strain. League guidelines should focus on reducing contact injuries within youth baseball, and injury-prevention programs should focus on reducing lower extremity injuries in youth softball.

Effects of a Sport-Specific Upper-Body Resistance-Band Training Program on Overhead Throwing Velocity and Glenohumeral Joint Range of Motion

Oranchuk, DJ, Ecsedy, EN, and Robinson, TL. Effects of a sport-specific upper-body resistance-band training program on overhead throwing velocity and glenohumeral joint range of motion. J Strength Cond Res XX(X): 000-000, 2020-Practitioners seek optimal, yet practical means to enhance performance while aiming to minimize injury risk. Resistance bands offer portability and safety and enable similar movements to competition. However, the effect of movement-specific resistance-band training on throwing performance and markers of injury risk has yet to be elucidated. Therefore, the purpose of this study was to compare the effects of a resistance training program using resistance bands with sport-specific (SS), or general-training (GT) exercises. Twenty-eight collegiate female softball players were randomly allocated to an SS (n = 15) or GT (n = 13) 8-week resistance-band program. Dependent variables included peak and mean throwing velocity, 1 repetition maximum (1RM) cable Chop-test, and glenohumeral internal and external rotation range of motion (ROM). No significant (p ≤ 0.338) differences were found between groups at baseline. Improvements in peak (p = 0.006, 4.9%, effect size [ES] = 0.61) and mean (p = 0.004, 3.1%, ES = 0.49) throwing velocity were seen after SS training, while the 1RM Chop-test increased in both SS (p < 0.001, 23.5%, ES = 1.06) and GT (p = 0.049, 26.1%, ES = 0.57) groups. However, no between-group differences (p ≥ 0.109, ES ≤ 0.17) were present in any variable. Neither the Chop-test nor shoulder internal or external ROM had more than moderate correlations with throwing velocity (r ≤ 0.30, p ≥ 0.119). Therefore, practitioners should not depend solely on SS resistance-band training when aiming to improve throwing velocity or measures of shoulder rotational health. However, resistance bands appear to be a practical alternative when traditional means of resistance training are not available. In addition, strength and conditioning coaches should not use the Chop-test or shoulder ROM to predict throwing performance.

Task constraints and stepping movement of fast-pitch softball hitting

This study aims to clarify the relationship between task constraints and the preparatory movement of fast-pitch softball batters in Japan for three different competition categories, namely high school, college, and league. As task constraints, we focused on the temporal and tool constraints and evaluated preparatory movements using initiation time and step duration of the stepping movement in a striking action. First, we confirmed the temporal constraints in each category and then examined the relationship between the temporal constraints and the stepping movements. The results demonstrated that the temporal constraints affected both initiation time and step duration of the stepping movements. Hierarchical cluster analysis was applied to the two variables. Consequently, the stepping movement of the softball players was classified into three types: “late initiation–short duration” (LS), “early initiation–short duration” (ES), and “early initiation–long duration” (EL) corresponding to the task constraints. Finally, the relationship between the task constraints of each category and the stepping movements was examined. The results revealed that high school players exhibited mostly the LS- or EL-type stepping movement; college players exhibited mostly the EL-type stepping movement; and league players exhibited all types. These results depict that the players in each category with each temporal and tool constraint exhibited particular types of stepping movements as a preparatory movement corresponding to each task constraint, thereby arguing that players use a not-to-lose strategy exploiting the redundancy in solutions under various task constraints.

The relationship of elbow alignment and kinematics on shoulder torque during the softball pitch: a biomechanical analysis of female softball pitchers

BACKGROUND

Female softball pitchers commonly throw more pitches per game and season than their baseball counterparts. The greatest stress to the shoulder during a softball windmill pitch is at ball release (BR). This study investigated shoulder torques at BR among female softball pitchers and identified relationships to the kinematics of the elbow and forearm and alignment of the elbow (carrying angle and elbow extension).

METHODS

High-speed 3-dimensional biomechanical analyses were performed in 33 pitchers (25 high school, 8 collegiate). Elbow and shoulder biomechanics at BR during fastball pitches and goniometric measures of carrying angle and elbow extension were collected and analyzed.

RESULTS

Carrying angle correlated positively with shoulder extension torque at BR (r_s = 0.371, P = .048) and forearm pronation at BR (r_s = 0.370, P = .048). During the windmill pitch, the greater the elbow flexion, the greater shoulder adduction torque at BR (r_s = -0.522, P = .007). Multiple regression analysis revealed that the carrying angle, passive elbow extension, and elbow flexion/extension angle at BR predicted shoulder flexion/extension torque at BR (F_3,24 = 3.463, R² = .302, P = .032.) CONCLUSIONS: Our findings demonstrate that shoulder torques during the softball fastpitch are influenced by the carrying angle and the kinematic elbow flexion angle at BR. Sports medicine clinicians and coaches should consider the role that the elbow carrying angle plays in creating shoulder stress when treating and training fastpitch softball players.

Effect of a High-Intensity Isometric Potentiating Warm-up on Bat Velocity

Gilmore, SL, Brilla, LR, Suprak, DN, Chalmers, GR, and Dahlquist, DT. Effect of a high-intensity isometric potentiating warm-up on bat velocity. J Strength Cond Res 33(1): 152-158, 2019-This study examined the acute effect of a high-intensity isometric potentiating warm-up on subsequent maximal horizontal bat velocity in experienced female softball players (n = 28). The isometric potentiating warm-up consisted of 3 sets of 5-second maximal voluntary contractions held in the early swing phase position, pulling against an immovable device. As one of the simplest methods to use the postactivation potentiation (PAP) stimulus, the warm-up was designed to acutely enhance muscle performance by inducing PAP. Because optimal recovery duration after a potentiating warm-up can be highly variable, swing trials were conducted at predetermined rest intervals (1, 2, 4, 6, 8, 10, and 12 minutes) to identify the recovery time that may have allowed for maximal possible benefits. Bat velocity was measured immediately before bat-ball impact using MaxTRAQ motion analysis software. The results showed that maximal horizontal bat velocity was significantly enhanced 6 minutes after the isometric warm-up protocol (+1.27 m·s, +2.84 mph, +4.93%; p < 0.05). In experienced female softball athletes, a specific isometric warm-up may acutely enhance maximal horizontal bat velocity.

Dominant-limb range-of-motion and humeral-retrotorsion adaptation in collegiate baseball and softball position players

CONTEXT

Biomechanically, the motions used by baseball and softball pitchers differ greatly; however, the throwing motions of position players in both sports are strikingly similar. Although the adaptations to the dominant limb from overhead throwing have been well documented in baseball athletes, these adaptations have not been clearly identified in softball players. This information is important in order to develop and implement injury-prevention programs specific to decreasing the risk of upper extremity injury in softball athletes.

OBJECTIVE

To compare range-of-motion and humeral-retrotorsion characteristics of collegiate baseball and softball position players and of baseball and softball players to sex-matched controls.

DESIGN

Cross-sectional study.

SETTING

Research laboratories and athletic training rooms at the University of North Carolina at Chapel Hill.

PATIENTS OR OTHER PARTICIPANTS

Fifty-three collegiate baseball players, 35 collegiate softball players, 25 male controls (nonoverhead athletes), and 19 female controls (nonoverhead athletes).

INTERVENTION(S)

Range of motion and humeral retrotorsion were measured using a digital inclinometer and diagnostic ultrasound.

MAIN OUTCOME MEASURE(S)

Glenohumeral internal-rotation deficit, external-rotation gain, total glenohumeral range of motion, and humeral retrotorsion.

RESULTS

Baseball players had greater glenohumeral internal-rotation deficit, total-range-of-motion, and humeral-retrotorsion difference than softball players and male controls. There were no differences between glenohumeral internal-rotation deficit, total-range-of-motion, and humeral-retrotorsion difference in softball players and female controls.

CONCLUSIONS

Few differences were evident between softball players and female control participants, although range-of-motion and humeral-retrotorsion adaptations were significantly different than baseball players. The throwing motions are similar between softball and baseball, but the athletes adapt to the demands of the sport differently; thus, stretching/strengthening programs designed for baseball may not be the most effective programs for softball athletes.