The Core or central area corresponds to the nucleus, or group of muscles located in the central part of the body. This muscle complex is crucial for athletic performance. This central area of the body, which encompasses the muscles of the abdomen, lower back, but-tocks, and pelvis, plays a critical role in several aspects of different sports. A strong core provides stability, improves the transfer of power from the legs to the pedals, maintains a proper posture on the bike, increases energy efficiency by allowing you to maintain an aerodynamic position for longer, prevents injuries by protecting the spine, improves balance. The muscles of the spine, trunk, abdomen and hips must be able to accelerate and decelerate the movements of the upper and lower limbs in a harmonic, coordinated and fluid synchrony (1). Maintaining a good stability of this complex depends mainly on an adequate interaction between the passive, active and neural subsystems (2). In this way, the core can be considered as a link and the center of almost all kinetic chains, playing an important role in maximizing the functions of the upper and lower extremities and athletic performance (3).

The importance of the function of the central core of the body for stabilization and force generation in all sports activities is increasingly recognized. “Core stability” is considered critical for efficient biomechanical function that maximizes force generation and minimizes joint loads in all types of activities, from running to throwing (4).

For example, in cycling the core muscles maintain the neutral pelvic position on the bike when both anterior and posterior muscle components are balanced (5). To prevent injury, proper bike adjustment is critical so that constant, low limb alignment is adopted throughout the ride (6). However, decreased core strength could artificially induce misalignment of the lower extremity in an effort to maintain a certain posture, while factors related to core stability may predict the risk of knee injuries (7, 8).

The impact of core strength training on lower limb power in athletes is an area that, to date, lacks sufficient conclusive studies. This gap in the scientific literature justifies the need for our research, which focuses on examining the relationship between core area muscle training and strength development in athletes. Therefore, the objective of this study is to provide a systematic review of the literature of core muscle training and its impact on athletic performance.

Traditionally, training to improve performance in sport has focused on the direct strengthening of the lower or upper limbs, prioritizing exercises such as squats, deadlifts and leg presses, among others also for upper limbs. Several studies have shown the effectiveness of these exercises to increase strength and power in the arms and legs. For example, Ronnestad et al. found significant improvements in the power of cyclists after a strength training program focused on the legs (9). Similarly, increases in maximum lower limb strength have been reported in cyclists after a period of weight training (10). However, emerging evidence suggests that a strong core is essential to optimize lower extremity function.

The effect of core training on leg strength and athletic performance is a topic that needs further investigation. Although there are some studies looking at how core stability affects athlete performance, there is little specific work on how core strengthening influences strength and power. This creates a lack of information in this field. Therefore, this research tries to fill this gap in the scientific literature, studying the relationship between the training of the core muscles and the increase of different variables such as speed, agility, power, among other variables of sports performance.

This study was conducted following the recommendations of the Cochrane Collaboration and the PRISMA statement. El protocolo fue registrado en el registro prospectivo internacional de revisiones sistemáticas (PRÓSPERO): CRD420251036787.

The review focused on studies that included the following PICO structure: Population(P): Competitive athletes (between 18 and 65 years old, of both sexes) who regularly participated in competitions at the regional, national or international level. This broad age range was chosen to ensure a comprehensive search that would be inclusive of masters-level competitive athletes. Intervention (I): Core training programs (e.g., planks, stability exercises, Swiss ball training). Comparison (C): absence of core training, alternative workouts (such as limb-centered strength training), or control groups. Results (O): primary: core strength (measured by isometric or endurance tests such as plank time); secondary: dynamic balance (e.g., Star Excursion Balance Test), sprint speed (such as times in 10–20 m sprints), jump height (such as countermovement jumping), agility (e.g., Illinois Agility Test), and sport-specific performance (such as striking speed in soccer).

304 studies were initially identified from database searches. After excluding duplicate studies, 107 studies were evaluated by title and abstract, of which 90 were excluded be-because they were systematic reviews, letters to the editor, intervention protocols or because they were not related to the topic of interest. Subsequently, 17 full-text studies were analyzed, of which 7 did not meet the inclusion criteria, and finally, 7 studies were evaluated with the PEDro scale, which were finally included in this review (Figure 1).

This systematic review analyzed the effect of core strength training on athletic performance in athletes of different practices. After an exhaustive literature search, 7 studies (11–17), were identified which met the inclusion criteria, evaluated with the PEDro scale (mean score of 5 points). The studies, predominantly controlled clinical trials, covered various sports disciplines (football, volleyball, basketball, badminton, Pencak Silat and running) and geographical contexts (Asia, Europe and America). The total sample of participants, aged between 10 and 40 years, was predominantly male. The considerable heterogeneity in training methodologies, which encompassed variations in duration (ranging from 4 to 9 weeks), frequency, and modalities (e.g., Swiss ball, slings, stable and/or unstable surfaces) together with the diversity of performance parameters assessed, constitutes an inherent limitation for evidence synthesis and adds complexity to the interpretation and generalization of findings. This variability may have masked specific effects or contributed to the inconsistency of certain outcomes, underscoring the difficulty of establishing optimal and universally applicable core training protocols based solely on the current body of studies.

The most researched variables were core strength, dynamic balance, and sprint speed. Core strength, measured through the maximum isometric force (MIF) of trunk flexors and extensors, showed dissimilar results. While extender MIF improved consistently after training, as reported by Prieske et al. (15), in elite young footballers, flexor MIF did not experience significant changes in most studies, consistent with the observations of Ozmen and Aydogmus (12), in badminton players. This discrepancy could be attributed to the greater involvement of trunk extensors in postural stabilization and force transfer during sports practice (4). In contrast, the results for maximal isometric trunk flexor strength (MIF) were less conclusive, with most studies reporting no significant changes. This discrepancy, compared with the improvements observed in the extensors, may be due to the fact that the reviewed core training protocols did not sufficiently emphasize maximal loading of the flexors, or that the nature of the exercises prioritized stability and endurance over maximal strength in this direction. It is possible that the neural and structural mechanisms involved in isokinetic flexor strength require different or more specific training stimuli than those implemented in the included studies. Core endurance, as assessed by plank, aft, BET, and SBT, improved after the intervention, showing an increase in endurance times. This result is similar to different previous studies demonstrating the efficacy of core training to improve the endurance of the trunk musculature (18). Similarly, research has been conducted on core stability exercises that strengthen the abdominal, lower back, and pelvic muscles, improving stability and control during the throwing motion (19).

Dynamic balance, assessed primarily with SEBT, showed significant improvements in all three axes of movement (anterior, posteromedial, and posterolateral), particularly in the group that trained on unstable surfaces (12). However, it is important to consider that the magnitude of the improvement in balance may vary according to the level of previous training of the athletes, as suggested by Granacher et al. (20), in their study with adolescents. In terms of sprint speed, most studies, including that of Prieske et al. (15), showed significant improvements, especially over short distances. This could be explained by the greater stability of the core, which allows a more efficient transfer of force to the lower extremities during the stroke (21).

Similarly, the results for countermovement jump (CMJ) height were inconsistent, with some studies reporting improvements while others did not. The CMJ is a multifactorial action that largely depends on lower-limb explosive strength, intermuscular coordination, and jump technique (22). Core training, while essential for providing a stable base, is unlikely to be the primary limiting factor for CMJ performance in athletes; rather, its impact may be more indirect and contingent upon integration with plyometric and lower-limb strength training. With respect to agility, as assessed through tests such as the T-Test or Illinois Agility Test, the results were particularly weak and showed no consistent improvements in most studies following core training (12, 15). This finding suggests a limited transfer from isolated core training to agility. Agility is a complex skill that not only requires trunk stability and strength but also cognitive components (perception and decision-making), rapid changes of direction, acceleration and deceleration, and braking ability. While a strong core provides a foundation, specific agility training that integrates these elements in sport-related contexts is essential to achieve meaningful improvements (23, 24). Therefore, core training may be more effective as a foundational component that prepares athletes for more specific and functional agility programs, rather than serving as a substitute for them.

Finally, in studies that evaluated specific sports performance, such as kick speed in soccer (14), improvements were observed after core training. However, the magnitude of these findings and their statistical significance were variable. This reinforces the importance of the principle of specificity in training, where adaptations are specific to the type of activity performed (25), also as Hawley points out, which indicates that this principle predicts that the closer the training routine comes to the requirements of the desired result (i.e., a specific exercise task or performance criteria), the better the result (26).

In summary, core training seems to have a positive effect on the different variables studied such as the strength of the trunk extenders, core resistance, dynamic balance and sprint speed.

Finally, it is imperative to acknowledge the inherent limitations of the included studies that affect the reliability of our findings. Most trials involved relatively small sample cohorts (ranging from 8 to 30 participants), which reduces statistical power and limits the generalizability of the results to broader athletic populations. Furthermore, while our inclusion criteria encompassed a broad age range (18–65 years) to potentially include masters athletes, the literature search only yielded studies with participants up to 40 years of age. Consequently, our findings cannot be generalized to older competitive athletes, and the effects of core training in that specific demographic remain an area for future investigation. Moreover, methodological quality, as assessed with the PEDro scale (average score of 5), revealed frequent omissions in therapist and assessor blinding. The lack of therapist blinding introduces a risk of performance bias, while the absence of assessor blinding may lead to detection bias, whereby the expectations of researchers or participants influence the reported outcomes. These methodological factors must be critically considered when interpreting the magnitude and consistency of the effects of core training.

Despite the limitations to which this review was subjected, due to the number of studies selected and the heterogeneity in the methods used by them, the findings suggest that core musculature training could constitute a valuable tool for improving certain performance parameters in sport. Overall, there is a trend toward improvement in trunk extension strength, core endurance, dynamic balance, and sprint speed in athletes who added core training to their training protocols. However, results regarding trunk flexor strength, CMJ height, and agility were inconclusive. These results have scientific and clinical implications. From a scientific perspective, it is proposed that future research adopt more rigorous methodological control, including appropriately calculated sample sizes to ensure statistical power and representativeness. Prioritizing assessor blinding and, whenever ethically feasible, participant or therapist blinding is crucial to minimize the risk of detection and performance bias. More homogeneous training protocols are recommended; alternatively, any heterogeneity should be explicitly justified and discussed to enhance understanding of the specific relationship between core training and components of sports performance. Future research should also explore designs that allow for the analysis of interactions between core training and other training modalities (e.g., plyometric, agility-specific), in order to better elucidate how the core contributes to holistic and functional athletic performance. From a clinical perspective, these preliminary results suggest that exercises that focus on the core area would be beneficial for athletes in various sports, particularly those that focus on endurance and dynamic stability. Contributing in this way to the improvement of strength, speed and balance. Even so, it is necessary to act with caution when generalizing these findings, due to the limitations presented and the variability in the individual response to training. Sports and health professionals are encouraged to take into account the specificity of each sport and the individual needs of athletes when designing and implementing core area muscle training programs.