Relationship between balance and maximum strength in weight-bearing and non-weight-bearing closed kinetic chain exercises

Balance and strength are important abilities that athletes should have them. This study was designed to investigate the relationship between maximum leg press (non-weight bearing closed kinetic chain) and squat (weight bearing closed kinetic chain) strength with statistic and dynamic balance. Thirty (15 men and 15 women) physically active participants (age, 22.13 ± 1.54 years; height, 171.26 ± 6.92 cm; weight, 66.02 ± 8.27 kg) completed the study. The Biodex Balance System was used to evaluate balance performance. Subjects completed two, 40 seconds trials attempting to maintain their statistic and dynamic balance and Overall Stability Index, Anterior/Posterior Index and Medial/Lateral Index were obtained. Maximum strength also was measured with a 1RM squat and leg press. Significant correlations were found between the measurements of 1RM squat with static anterior-posterior indices (r, 0.019; P=-0.541) and dynamic medial-lateral indices (r, 0.021, P=-0.532) in men and with static anterior-posterior indices (r, 0.016, P=-0.552) and dynamic anterior-posterior indices (r, 0.032; P=-0.491) in women. No significant correlations were found between the measures of 1RM leg press and balance indices in both groups. The results of this study indicate that maximum squat strength has more relation with some indices of static and dynamic balance than maximum leg press.