Background The Y-balance test has been used clinically to assess neuromuscular control deficits and a composite score of <94% and anterior asymmetry of >4 cm have been associated with lower limb injuries in basketball athletes.

Objective To compare Y-test performance during the pre-season to in-season in injury-free athletes.

Design Prospective study.

Setting Brazilian sports club, mixed sports.

Patients (or Participants) 182 injury-free youth athletes (145 male and 37 female) from judo, volleyball, basketball, gymnastics and indoor soccer were assessed (age 14.3±2.8; height 168±19 cm, body mass 60±18 kg).

Assessment of Risk Factors The Y-test was assessed during the pre-season (February) and in-season (June). Athletes practiced 6 trials on each leg prior to formal testing. While maintaining single-leg stance, they were asked to reach with the free limb in the anterior, posteromedial, and posterolateral directions.

Main Outcome Measurements Y-test performance was calculated as the composite score (sum of the three reach distances, divided by 3 times limb length, then multiplied by 100). Anterior distance asymmetry was calculated as the difference between the dominant limb (DL) and non-dominant limb (NDL) values. Both measures were compared between pre- and in-season.

Results The pre-season average composite score for DL was 87.5% and for NDL 87.8%, while the average anterior distance asymmetry was 3.7 cm. During in-season, the average composite score was 85.4% for DL and NDL, and the anterior distance asymmetry was 3.0 cm. T-tests revealed statistically significant differences for the composite score (p<0.001) and for anterior distance asymmetry (p=0.01).

Conclusions Athletes showed poorer composite score values during in-season compared to pre-season and the values were below the risk cut-off point reported in the literature. This group did not present substantial anterior distance asymmetry.