Hubbry Logo
Ballistic trainingBallistic trainingMain
Open search
Ballistic training
Community hub
Ballistic training
logo
8 pages, 0 posts
0 subscribers
Be the first to start a discussion here.
Be the first to start a discussion here.
Ballistic training
Ballistic training
from Wikipedia
Ballistic training consisting of throwing medicine balls. Note the preparatory crouched posture which preloads the legs and core. This helps to increase the power of the throw.

Ballistic training, also known as compensatory acceleration training,[1][2] uses exercises which accelerate a force through the entire range of motion.[1][3] It is a form of power training which can involve throwing weights, jumping with weights, or swinging weights in order to increase explosive power.[4] The intention in ballistic exercises is to maximise the acceleration phase of an object's movement and minimise the deceleration phase. For instance, throwing a medicine ball maximises the acceleration of the ball.[5] This can be contrasted with a standard weight training exercise where there would be a pronounced deceleration phase at the end of the repetition i.e. at the end of a bench press exercise the barbell is decelerated and brought to a halt. Similarly, an athlete jumping whilst holding a trap bar maximises the acceleration of the weight through the process of holding it whilst they jump- where as they would decelerate it at the end of a standard trap bar deadlift.[6]

History

[edit]
Depiction of a stone put training method from the Swiss Lucerne Chronicle, 1513. Note the preloading of the back leg.

The word ballistic comes from the Greek word βάλλειν (ballein), which means “to throw”. Evidence of ballistic training can be seen throughout recorded history, especially in depictions which show the throwing of a large stone (stone put). Other ballistic disciplines from antiquity include the javelin throw and the discus throw. The hammer throw is a younger discipline, known from the 16th century.[7]

Such throws have been both a popular sporting pastime, and a training method employed by soldiers. Ballistic training was first used in the modern day by elite athletes when they were looking to enhance their ability to perform explosively. Commonly used modern ballistic training exercises are medicine ball throws, bench throws, jump squats, and kettlebell swings.[4]

Focus and effects

[edit]
Throwing a large stone is a traditional form of ballistic training, with records of it dating from Ancient Greece.[8] Because the stone is released into the air, there is no need to slow it to a halt like in a standard weight training exercise. Modern ballistic training theory maintains that due to this the body can be conditioned to accelerate more against resistance, with less of an emphasis on deceleration, and thus become more explosive.[4]

Ballistic training requires the muscles to adapt to contracting very quickly and forcefully. This training requires the central nervous system and muscular system to coordinate and produce the greatest amount of force in the shortest time possible i.e. to increase the rate of force development (RFD).[9]

Ballistic training exercises involve dramatically increasing the acceleration phase of the weight's movement and reducing the deceleration phase. For example, in a medicine ball throw the weight is accelerated throughout the exercise in order to propel it into the air. In a weighted jump, the weight continues to be held and so continues to be accelerated throughout the concentric phase of the jumping action. This can be contrasted with standard weight training exercises where the weight is decelerated and brought to a halt at the end of the repetition. For example, in a bench press the barbell is decelerated to a halt at the end of a standard repetition, but in a bench press throw it continues to be accelerated as it is thrown into the air. An exercise performed in a ballistic manner allows for the weight to be moved more forcefully.[10]

Criteria

[edit]

1. Muscle recruitment principles. Ballistic lifts force the muscles to produce the greatest amount of force in the shortest amount of time. In accordance with Henneman's size principle muscle fibers are recruited from a low to a high threshold as force requirements increase.

2. Speed of the movement. To ensure full muscle fiber recruitment the speed of the lift must be propulsive through the entire range of the movement up until release.

3. Intensity of the exercise. The duration of the lift should be measured by repetitions or time. The lift should be stopped when the bar decelerates. Research has shown the 6-8 repetitions or 20–30 seconds produces the best results.

4. Cardiovascular benefits. Ballistic exercises performed continuously for a minimum of 20 seconds followed by a 30-second rest period and then repeated until deceleration occurs has been proven to elevate the heart rate to training zone level.[11]

5. Co-ordination. Research at the University of Connecticut found that high-intensity training has profound effects on the nervous system. The exercise had to be of an intensity that elevate the heart rate to 90% of maximum rate and had to sustain that rate for at least 20 seconds.

6. Electronic measurement. There are several electronic measurement systems that measure the velocity, power, and effectiveness of a lift. The athlete should stop the lift when the speed of a lift has fallen to 90% of their previous lift. The 90% number signals that there has been a significant change in the recruitment of the fast-twitch muscle fibers. Below the 90% number the lift is no longer ballistic

7. Specificity of training. Ballistic training emphasizes throwing and jumping with a weighted object. Research has resulted in positive increases in vertical jump, throwing velocity, and running speed. There is limited transfer to a specific sport.

Use in metabolic conditioning

[edit]

Ballistic exercises have traditionally been left out of metabolic conditioning workouts and training programs. This may be due to the fact that they are often technical lifts, or lifts/exercises for which technique is crucial to safe and effective completion. However, with the extensive availability of information and guidance in learning and developing proficiency in ballistic exercise, this trend is changing.[citation needed]

Many training programs which employ circuit training or metabolic conditioning now include ballistic exercises such as kettlebell cleans and snatches, Olympic lifts and variations, throws and plyometric variations. The benefits of their inclusion in these types of programs include higher levels of motor unit recruitment, higher caloric burn and improvements in a number of measurable athletic outputs.[citation needed]

See also

[edit]

References

[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia
from Grokipedia
Ballistic training is a specialized form of power development in strength and conditioning that emphasizes , high-velocity movements to accelerate the body or an external load through the full without a deceleration phase, projecting it into a flight or release phase. This method focuses on maximal intent to move quickly, typically using low to moderate loads (0–90% of , or 1RM), to enhance neural drive and neuromuscular efficiency rather than maximal strength alone. Unlike traditional resistance training, which often involves controlled eccentric and concentric phases with deceleration at the end of the movement, ballistic training prioritizes continuous acceleration to mimic sport-specific actions like , , or striking. Key principles of ballistic training revolve around optimizing the force-velocity relationship, where lighter loads allow for higher velocities to target fast-twitch muscle fibers and improve rate of force development (RFD). Exercises commonly include variations of Olympic lifts (e.g., power cleans), jump squats with or without added weight, throws, and slams or throws, all performed with an emphasis on explosive concentric actions. To ensure safety and efficacy, ballistic training is typically introduced after athletes have built a foundation of general strength, as the high-speed nature increases injury risk if foundational stability is lacking. The benefits of ballistic training are well-supported in exercise science, particularly for improving explosive power, speed, and athletic performance in dynamic sports. Research demonstrates that it enhances countermovement jump height by approximately 3.6%, peak velocity by 5.1%, and power output by 2.6% when used as a , with effects persisting up to 24 hours post-exercise. In team sports such as , short-term ballistic programs have been shown to increase throwing velocity, muscle volume, and overall power without compromising in-season recovery. These adaptations stem from improved , inter- and intra-muscular coordination, and specificity to ballistic actions, making it a valuable tool for athletes in sports requiring rapid force production.

Fundamentals

Definition and Purpose

Ballistic training is a specialized form of resistance that emphasizes maximal-velocity concentric muscle contractions with minimal or no eccentric deceleration phase, often involving the projection of the athlete's body weight or external implements—such as medicine balls or barbells—into free flight. This approach accelerates a load through the full until release, allowing for unloaded in the latter portion of the movement, which distinguishes it from traditional where deceleration occurs against resistance. The primary purpose of ballistic training is to enhance the rate of force development (RFD), explosive power, and speed-strength qualities essential for athletic performance in sports demanding rapid, high-force actions, such as sprinting, jumping, and throwing. By targeting the high-velocity end of the force-velocity relationship, it promotes neuromuscular adaptations that improve the ability to generate force quickly, thereby boosting overall power output and translational athletic capabilities like speed and height. Unlike , which rely on the stretch-shortening cycle involving an eccentric preload followed by rapid concentric action to store and release , ballistic training prioritizes the pure phase post-release without significant eccentric loading. This focus on maximal intent for velocity makes it particularly suited for developing unloaded explosive movements.

Biomechanical Principles

Ballistic training leverages the fundamental inverse relationship between and in muscle contractions, as described by the force-velocity curve. This hyperbolic curve illustrates that maximal production occurs at low velocities, while maximal is achieved with minimal ; ballistic movements primarily operate at the high-velocity end of this spectrum, where output is moderate but approaches near-maximal levels to optimize explosive power generation. In these dynamics, the goal is to maximize the product of and , enabling rapid acceleration during the projection phase of movements such as throws or jumps. The power output in ballistic training is governed by
P=F×V,P = F \times V,
where PP represents power, FF is , and VV is . Maximal power (PmaxP_{\max}) is achieved when and are balanced at approximately 30-50% of their maximum values, corresponding to loads of 30-60% of (1RM) in many ballistic protocols. This relationship explains the emphasis on short, maximal efforts—typically 1-3 repetitions—since prolonged sets lead to decrements that shift the movement away from the optimal power zone, reducing the - efficiency and overall output.
While the stretch-shortening cycle (SSC) plays a partial role in certain ballistic variants involving brief eccentric loading followed by rapid concentric contraction, the primary focus remains on concentric-only phases to minimize dissipation associated with eccentric deceleration. In concentric-dominant ballistic actions, the absence of significant eccentric loading preserves for projection, avoiding the dissipative forces that can occur during lengthening contractions and allowing for higher load utilization during . Neural adaptations underpin these biomechanical principles, particularly through post-activation potentiation (PAP), where preceding heavy loads (e.g., >80% 1RM) acutely enhance subsequent ballistic performance by increasing and firing rates. This phenomenon, lasting 4-12 minutes post-stimulation, facilitates greater of regulatory light chains, thereby boosting contractile force without altering the fundamental force-velocity profile.

Historical Development

Origins in Physical Training

The roots of ballistic training extend to ancient civilizations, including , where athletes practiced throwing heavy stones to develop explosive power, as evidenced in early records of physical feats dating back to around 2600 BCE in related cultures. Ballistic training, characterized by explosive movements to develop rapid force production, traces its conceptual foundations to early 20th-century , particularly within traditions that emphasized dynamic lifts over static strength. Pioneers like integrated explosive techniques into their routines, such as the one-hand snatch and single-handed dumbbell swing, where the lifter pulls the weight rapidly from the ground and jerks it overhead using leg drive and violent wrist action to maximize power output. These methods, detailed in Saxon's 1906 publication The Development of Physical Power, focused on speed and coordination rather than slow, controlled repetitions, drawing from circus performance demands for spectacular feats of power. Similarly, in Eastern European circles, dynamic throws and jerks became staples, influencing training that prioritized explosive power for athletic and Olympic preparation during the 1910s and 1920s. Military applications further shaped these early practices, with Soviet training systems in the 1920s and 1930s adopting ballistic elements for soldiers and athletes. Athletics coaches in Northern and , including Soviet regions, began prescribing plyometric-style jump and throw sessions from 1919 to 1930, laying groundwork for power development in combat and sport contexts. Key figure , a British strongman active in the early 1900s, advanced these ideas by incorporating ballistic components like kettlebell snatches and overhead bell throws into strongman routines, as outlined in his 1905 book Scientific Weight-Lifting. Inch's methods stressed rapid leg and arm extension for jerks and swings, promoting power through mechanical efficiency and explosive coordination in vaudeville and stage performances. Prior to the 1950s, ballistic training lacked rigorous scientific validation, relying heavily on anecdotal reports from strongmen, circus performers, and instructors who observed performance gains from explosive drills but documented them informally through personal manuals and demonstrations. These pre-scientific approaches, while effective for building in anecdotal cases, often overlooked risks due to the absence of biomechanical analysis or controlled studies. Post-World War II, these foundations evolved into more evidence-based frameworks.

Evolution in Modern Sports Science

The integration of ballistic training into modern began in the mid-20th century, building on earlier training roots to emphasize power development. In the , Soviet coach Yuri Verkhoshansky pioneered the "shock method," evolving depth jumps into structured ballistic protocols that enhanced reactive strength for Olympic weightlifters and track athletes. This approach was formalized through Verkhoshansky's research, which demonstrated how brief, high-impact loading could improve speed-strength qualities, influencing training systems. By the 1970s and 1980s, Western adoption accelerated, with U.S. track coach Fred Wilt coining the term "" in 1975 to describe similar explosive techniques observed in Soviet athletes, thereby popularizing ballistic methods in American coaching. Concurrently, Italian physiologist Carmelo Bosco's studies in the late 1970s quantified explosive power through metrics like the stretch-shortening cycle in ballistic jumps, providing empirical validation via force platform measurements. The National Strength and Conditioning Association (NSCA), founded in 1978, began standardizing ballistic protocols in the 1980s through its journal and position statements, recommending them for power athletes to optimize rate of force development (RFD) without excessive loading. From the 1990s onward, technological advancements refined ballistic training's application. Force plates became integral for precise RFD assessment during ballistic movements, enabling in elite sports labs. The 2000s saw broader popularization through the rise of and , which incorporated ballistic elements like medicine ball throws into high-intensity circuits, expanding access beyond specialized athletics. Globally, adoption surged in team sports; for instance, NFL combines standardized ballistic tests such as vertical and broad jumps to evaluate power, influencing scouting and training worldwide. Recent meta-analyses have solidified its evidence base, confirming ballistic training's role in power enhancement across populations.

Training Methods

Core Exercises

Core exercises in ballistic training emphasize explosive movements that involve rapid acceleration and projection of the body or an implement, targeting specific muscle groups through high-velocity actions. These exercises are designed to align with the force-velocity curve, optimizing power output by prioritizing speed over maximal load. Upper-body ballistic exercises focus on the pectorals, deltoids, , and core stabilizers, utilizing throws to achieve maximal release velocity. The medicine ball chest pass involves standing with feet shoulder-width apart, holding a at chest level, and explosively extending the arms forward while releasing the ball with a forceful push, targeting horizontal power projection. The overhead slam requires gripping a overhead, then driving it downward explosively toward the ground using a whipping motion from the shoulders and core, emphasizing vertical force application and rapid eccentric-to-concentric transition. Rotational throws, such as side tosses, position the body in a staggered stance with the held near one hip, then rotate the torso and release the ball sideways at maximal speed, engaging obliques and promoting asymmetric power development. In all cases, the mechanics prioritize a full acceleration phase ending in release, avoiding deceleration to maximize velocity. Lower-body exercises target the , glutes, hamstrings, and calves through jumping actions that demand triple extension of the ankle, , and joints for optimal force transfer. Box jumps with weights involve holding light dumbbells or a , performing a quarter squat, and exploding upward onto a while maintaining an upright , focusing on height and control upon landing. Squat throws require squatting with a held between the legs, then rapidly extending the hips and knees to throw the ball upward or forward, simulating explosive lower-body propulsion. Broad jumps start from a standing position, with a countermovement squat followed by a horizontal leap for distance, emphasizing forward momentum through triple extension without added load. These movements highlight the coordinated extension of lower-limb joints to generate peak power. Full-body and Olympic-style variants integrate multiple muscle groups, differentiating from traditional lifts by intent on projection rather than controlled lowering. Power cleans feature a ballistic catch phase where the barbell is pulled explosively from the floor or hang position via triple extension, then received in a quarter squat with rapid deceleration minimized during the pull. swings begin with a hip hinge to swing the between the legs, followed by a powerful hip snap to propel it forward to chest height, targeting the through ballistic hip extension without overhead lockout. This projection focus distinguishes them from standard cleans or deadlifts, which emphasize stability over velocity. Equipment variations allow adaptation across levels, using bodyweight for accessibility or light implements to prevent deceleration. Bodyweight clap push-ups execute as an explosive press-up where hands leave the ground for a mid-air clap, targeting pectorals and through rapid extension. Light implements, such as balls or kettlebells at 5-10% of bodyweight, ensure continuous in throws and jumps, preserving the ballistic nature without excessive loading.

Programming Guidelines

Programming ballistic training requires careful consideration of load, volume, and recovery to optimize power development while minimizing fatigue. Loads are typically selected at 30-60% of (1RM) to prioritize movement velocity and explosive intent, as this range elicits peak power outputs in ballistic movements such as throws or jumps. Progression begins with submaximal efforts using lighter loads within this spectrum and advances to near-maximal velocities over 4-6 weeks, allowing neural adaptations to build without excessive volume. Volume and frequency guidelines emphasize quality over quantity to support high-velocity repetitions. Programs commonly prescribe 3-5 sets of 1-5 repetitions per exercise, performed 2-3 times per week, to maintain output and allow for full recovery. Rest intervals of 2-5 minutes between sets are recommended to facilitate neural recovery and replenish stores, ensuring each repetition approaches maximal velocity. Integration strategies enhance ballistic training by pairing it with complementary methods within broader routines. Complex training, which alternates a heavy strength exercise with a ballistic counterpart, is a common approach; for instance, a set of back squats at 80-90% 1RM followed immediately by unloaded jump squats leverages post-activation potentiation to boost power. This method is often incorporated into periodized power phases using 4-week blocks, where ballistic elements increase in emphasis during the latter half to align with competitive demands. Progression models focus on systematic overload to sustain improvements in and power. Linear progression involves gradual increases in load or targeted speed across sessions, with adjustments of 4-5% 1RM if velocities deviate from benchmarks. Monitoring via velocity-based training (VBT) tools is essential, aiming to maintain repetitions at 80-90% of an individual's maximum velocity to ensure optimal stimulus without excessive .

Physiological Effects

Performance Benefits

Ballistic training enhances athletic performance primarily through improvements in power output and rate of force development (RFD), which are critical for explosive movements. Studies demonstrate that 6-8 weeks of ballistic protocols, such as loaded jump squats at 26-48% of , can increase peak power by approximately 40% and RFD by up to 100% in isometric assessments, independent of changes in maximal strength or muscle fiber composition. These gains often translate to moderate-to-large improvements in height (SMD ≈ 0.96) and sprint times over 10-40 m distances (SMD 0.92-1.28), as evidenced in meta-analyses of complex training programs incorporating ballistic elements. Such enhancements stem from optimized neuromuscular efficiency, including faster during rapid contractions. In sports-specific contexts, ballistic training facilitates direct transfer to by augmenting and in dynamic actions. For instance, players undergoing 10 weeks of ballistic resistance exercises, including bench throws and squat jumps at 30-50% 1RM, achieved 2-10% gains in throwing , with similar protocols yielding up to 10.7% increases in specialized resistance reviews. In soccer, short-term ballistic programs (4-8 weeks) improve change-of-direction speed through enhanced sprint and neuromuscular coordination, with meta-analytic effect sizes indicating moderate-to-large benefits (SMD 0.97-1.49) for tasks involving multiple turns. These adaptations support quicker acceleration and deceleration, vital for game scenarios. Ballistic training also contributes to metabolic improvements, particularly in anaerobic capacity, by promoting efficient energy utilization during high-intensity efforts. Research on collegiate athletes shows that 6 weeks of ballistic exercises significantly elevate anaerobic power, as measured by vertical and tests, outperforming traditional resistance training in explosive output. When integrated into , ballistic methods bolster short-burst tolerance without extensive endurance focus. Benefits are particularly pronounced in trained athletes compared to novices, with chronic strength-trained individuals exhibiting 29% greater absolute RFD after 4 weeks of maximal-intended-velocity ballistic training. Long-term adaptations include enhanced recruitment of type II fast-twitch fibers, optimizing power generation for sustained high-level performance.

Risks and Safety Considerations

Ballistic training's explosive, high-velocity movements can generate substantial eccentric loading on joints and soft tissues, increasing the risk of acute injuries such as shoulder impingement during throwing exercises and (ACL) strain from improper landing mechanics in jumps. Overuse injuries, including tendinopathies and stress fractures, may also arise from insufficient recovery, leading to cumulative microtrauma in muscles and connective tissues. This training modality is contraindicated for beginners without an established strength base, individuals with joint instability, or those in early post-injury recovery phases absent clearance, as these factors heighten to or reinjury. Overhead ballistic actions, such as medicine ball throws, pose elevated risks for rotator cuff tears or inflammation due to the rapid, repetitive demands on stabilizers. Safety protocols emphasize a thorough warm-up featuring dynamic mobility exercises to enhance neuromuscular readiness and reduce initial stress on tissues. Close supervision of technique is critical to correct form deviations and prevent faulty movement patterns that amplify joint stress. Novices should begin with scaled loads at 20-30% of one-repetition maximum to foster adaptation without overwhelming the musculoskeletal system. Ongoing monitoring for overtraining indicators, including reduced movement velocity, persistent pain, or technique breakdown, allows for timely program adjustments to safeguard participants. Evidence from supervised programs reports low rates, in contrast to elevated incidences in unsupervised environments where adherence to guidelines is lacking.

Applications

In Sports Performance

Ballistic training plays a pivotal role in enhancing explosive actions required in team sports, where rapid acceleration and power output are critical for competitive success. In , integration of ballistic-plyometric drills into strength and conditioning programs has been shown to improve acceleration over short distances, such as those simulated in the , with studies reporting significant reductions in sprint times following 6-8 weeks of training. Similarly, in , short-term ballistic protocols targeting maximal velocity have led to notable gains in height and sprint speed, aiding explosive starts and defensive movements, as evidenced by improvements in countermovement jump (CMJ) performance and sprint times in young elite players after 10 weeks. For soccer, ballistic exercises focusing on lower-body power have enhanced explosive capabilities, including shot power, through increased neuromuscular efficiency, with female players demonstrating superior explosive power outputs compared to controls after targeted interventions. In individual sports, ballistic training optimizes sport-specific explosiveness, particularly in disciplines demanding high-velocity force production. athletes benefit from methods incorporating ballistic elements, such as the French Contrast, that improve explosive strength and kinematic parameters in events like the . In sports like , ballistic upper-body exercises, including landmine punch throws, reliably increase punch velocity across varying loads, allowing athletes to develop faster strikes while maintaining technique under resistance, as peak velocities show strong linear relationships with load in trained boxers. Periodization of ballistic training is commonly employed in pre-season phases to build power foundations, typically spanning 8-12 weeks and integrated with skill-specific drills to peak performance for . This approach combines ballistic sessions with heavy resistance work, yielding sustained gains in strength without plateauing early, as seen in elite players where 8 weeks of ballistic exercise improved CMJ height by approximately 19% and sprint speed comparably to complex training methods. Progress in ballistic training is tracked using targeted metrics that quantify explosive gains, such as CMJ height, which reliably increases by 9-10% following plyometric or ballistic protocols, reflecting enhanced power output via improved muscle-tendon properties. Radar gun measurements of velocity, applied to actions like punches or throws, provide precise feedback on ballistic-specific improvements, with reliable load-velocity profiles enabling individualized adjustments in and . These assessments, often conducted pre- and post-intervention, help coaches monitor adaptations driven by power enhancements in the neuromuscular system.

In Rehabilitation and Conditioning

Ballistic training has been adapted for rehabilitation settings, particularly following injuries like (ACL) reconstruction, where low-load exercises such as light tosses help restore neuromuscular power while minimizing shear forces on the . These protocols typically progress in phases, beginning with isometric holds to build foundational stability before introducing controlled ballistic movements, such as bilateral lunges or drop jumps with ground reaction forces under 2 times body weight. This approach supports eccentric control and movement quality without overloading the graft, enabling safer power development during mid-to-late recovery stages. Evidence from criterion-based programs demonstrates significant post-surgical improvements; for instance, patients with initial 50% extensor strength deficits post-ACLR can achieve limb indices exceeding 90% after 12-16 weeks of integrated plyometric and ballistic training, representing substantial recovery in power output. For non-athletes, adaptations include reduced repetitions and lighter loads to accommodate lower fitness levels, ensuring while promoting functional gains. Safety modifications, such as monitoring for stress, further tailor these exercises to individual tolerances in therapeutic contexts. In general fitness applications, ballistic training integrates into (HIIT) circuits to enhance fat loss and cardiovascular conditioning through short bursts of 20-30 seconds, leveraging explosive movements like slams or swings. For older adults, controlled ballistic jumps or high-velocity resistance exercises help maintain density, with studies showing small but significant increases of 0.9% to 5.4% at sites like the lumbar spine and after at least two sessions per week. These adaptations prioritize , focusing on moderate intensities to support metabolic health without excessive risk. Ballistic elements also feature in metabolic conditioning protocols, such as CrossFit-style workouts of the day (WODs), where they elevate (EPOC) for prolonged calorie burn and aerobic adaptation. Formats like every minute on the minute (EMOM) incorporate ballistic exercises—e.g., repeated snatches or box jumps—to sustain high-intensity efforts, with research indicating EMOM structures induce notable EPOC alongside improved work capacity compared to continuous formats. This method fosters efficient conditioning for diverse populations, emphasizing recovery intervals to optimize metabolic responses.

References

  1. https://www.frontiersin.org/journals/[psychology](/page/Psychology)/articles/10.3389/fpsyg.2020.627869/full
Add your contribution
Related Hubs
User Avatar
No comments yet.