Early Sport Specialization and Intense Training in Junior Tennis Players: A Sport-Specific Review.

CONTEXT: Early sports participation can provide significant physical, psychosocial, and mental benefits for young athletes. Sports engagement can be via sport sampling or sport specialization. Sport specialization is often encouraged by parents and coaches as it is perceived as a mechanism for achieving elite level play, particularly in tennis. EVIDENCE ACQUISITION: A search on PubMed, Google Scholar, and Science Direct was conducted for pertinent peer-reviewed studies on sport specialization and overuse injuries in youth athletics and junior tennis using key terms including "junior tennis," "youth sports," "sport specialization," and "overuse injury." STUDY DESIGN: Clinical review. LEVEL OF EVIDENCE: Level 5. RESULTS: Early sport specialization leads to increased injury risk, decreased athletic career longevity, and higher incidence of burnout without demonstrating significant benefits in terms of improving peak sports performance or the likelihood of reaching elite play. CONCLUSION: Youth athletes should avoid specializing in a single sport before age 12, avoid training more hours per week than their age in years, and limit training to 16 hours per week maximum. Specific to tennis, junior players should be at least 12 years old for tournament play, compete in no more than 2 tournaments per month or 12 per year, engage in a maximum of 12 hours per week of organized tennis, a minimum of 2 hours per week of injury prevention training, and consider another off-season sport. Injury may be more likely with early sport specialization, early intense training (before middle or late adolescence) and annual match volume (>40 matches annually). Finally, we provide novel recommendations for safe volumes of training, matches, and tournaments for junior tennis players based on their age and level of play.Strength-of-Recommendation Taxonomy (SORT):B - recommendations based on inconsistent or limited-quality patient-oriented evidence.