Trends and Implications of Single-Sport Specialization in Professional Players
(A summary of the original article - see below)
In orthopedic physical therapy, we are often asked if a pre or young teen should focus on one sport or be exposed to many. As in most questions like this - it depends.
It depends on their physical and emotional development. It depends on what the individual's goals are. Are they truly (not in their parents mind, but truely) a pro prospect or are they shooting for collegiate rec league sports.

As our society becomes more and more focused on specialization the following study references the benefits of maintaining a multi-sport influence in one's athletic career. We only have to look at legendary athletes like Michael Jordan, Dion Sanders, Bo Jackson and Roger Federer to name a few that played multiple sports growing up before choosing and excelling at their disiplin.
Bringing the conclusion up front, this study challenges the prevailing trends of early youth sport specialization by highlighting that the majority of professional baseball athletes did not specialize in a single sport during their youth.
For those who did specialize, the average age of specialization was 14 years. The findings of this study raise concerns about the increasing trend of early specialization within baseball, especially considering the potential cumulative effects of pitching and overhead throwing on an athlete's arm.
Given the implications of specialization at a young age, it is important for athletes, parents, coaches, and sports organizations to critically evaluate the advantages and risks associated with early specialization. A well-rounded approach that promotes multi-sport participation and emphasizes the development of overall athleticism may prove beneficial for the long-term success and well-being of young baseball athletes.

This study we are referencing here (baseball athletes) challenges the prevailing trends of early youth sport specialization by highlighting that the majority of professional baseball athletes did not specialize in a single sport during their youth.
For those who did specialize, the average age of specialization was 14 years. The findings of this study raise concerns about the increasing trend of early specialization within baseball, especially considering the potential cumulative effects of pitching and overhead throwing on an athlete's arm.
Given the implications of specialization at a young age, it is important for athletes, parents, coaches, and sports organizations to critically evaluate the advantages and risks associated with early specialization. A well-rounded approach that promotes multi-sport participation and emphasizes the development of overall athleticism may prove beneficial for the long-term success and well-being of young baseball athletes.
In recent years, there has been a noticeable rise in the number of young baseball athletes who focus solely on playing baseball from an early age. This article aims to shed light on the prevalence and age at which professional baseball athletes specialize in a single sport. Furthermore, we will explore the patterns of single-sport specialization among professional baseball players, both within and outside the United States (US).

Study Design and Methods
The research conducted for this article employed a cross-sectional study design, with a Level of evidence categorized as 3. A survey was distributed to male professional baseball athletes through individual team athletic trainers. The athletes were asked about the age at which they decided to exclusively pursue baseball and abandon other sports. Detailed information was collected regarding the rate and age of specialization, reasons behind specialization, and the athletes' perception of injuries associated with specialization.
Findings
A total of 1673 professional baseball athletes, representing 26 out of the 30 Major League Baseball (MLB) organizations, participated in the survey. Surprisingly, less than half (44.5%) of the professional athletes reported specializing in playing a single sport during their childhood and adolescence. Among those who chose to specialize, the mean age at which they did so was 14.09 ± 2.79 years.
It is worth noting that MLB players who grew up outside the US specialized at a significantly earlier age compared to MLB players who were native to the US. The former group specialized at an average age of 12.30 ± 3.07 years, whereas the latter specialized at 14.89 ± 2.24 years (P < .001). Additionally, MLB players raised in the US recalled a significantly higher incidence of injuries attributed to specialization in baseball compared to MLB athletes raised outside the US (27.7% vs. 20.6%, respectively; P = .05).
Conclusion and Implications
This study challenges the prevailing trends of early youth sport specialization by highlighting that the majority of professional baseball athletes did not specialize in a single sport during their youth. For those who did specialize, the average age of specialization was 14 years. The findings of this study raise concerns about the increasing trend of early specialization within baseball, especially considering the potential cumulative effects of pitching and overhead throwing on an athlete's arm.
Given the implications of specialization at a young age, it is important for athletes, parents, coaches, and sports organizations to critically evaluate the advantages and risks associated with early specialization. A well-rounded approach that promotes multi-sport participation and emphasizes the development of overall athleticism may prove beneficial for the long-term success and well-being of young baseball athletes.
Orthop J Sports Med. 2020 Mar; 8(3): 2325967120907875.
Published online 2020 Mar 20. doi: 10.1177/2325967120907875
PMCID: PMC7092410
PMID: 32232067
Youth Single-Sport Specialization in Professional Baseball Players
Patrick S. Buckley, MD,* Michael C. Ciccotti, MD,†‡ Meghan Bishop, MD,‡ Patrick Kane, MD,§ Stephen Selverian, BS,* Dominique Exume, BS,* John D'Angelo, BA,∥ William Emper, MD,‡ Kevin B. Freedman, MD,‡ Sommer Hammoud, MD,‡ Steven B. Cohen, MD,‡ and Michael G. Ciccotti, MD‡