4-weeks Dynamic Balance training fails to improve ankle and knee joint position sense

Abstract

Objective: Research clearly shows that balance training improves balance and reduces recurrent injuries. However, the existing data is inconclusive about the effect of balance training exercises on proprioceptive outcomes. While some studies have reported positive effects of balance training on position sense other have reported insignificant findings. For that reason the purpose of this study was to determine if a dynamic balance training program centered on the use of unstable surface exercises can improve lower extremity joint position sense. Setting: University Research Laboratory Participants: Twelve healthy men (age: 22.5 ± 4.58 years, height: 181.58 ± 7.57 cm, weight:85.25 ±10.67 kg, BMI: 25.87 ± 3.01 kg/m 2 ) and 16 healthy women (age: 20.87 ± 3.4 years, height: 164.13 ± 6.15 cm, weight: 63.75 ±13.3 kg, BMI: 23.53 ± 3.94 kg/m 2 ) volunteered to participate. Intervention(s) : All participants underwent a total of 12 supervised training sessions over a 4-week period of time with each session lasting about 30 minutes. The specific exercises that were performed during each training session included: 1) hop to stabilization onto and off of a BOSU ball in four directions (anterior, lateral, anteriomedial, and anteriolateral; 2) mini-squats on a BOSU ball while in a single limb stance; 3) unanticipated reach sequences while stabilizing on a BOSU ball in a single limb stance; and 4) static single limb stance on a BOSU ball. Main Outcome Measure(s): Ankle joint position sense and knee joint position sense were assessed by a passive reproduction of passive positioning protocol. Target angles of 10° and 20° of inversion were used for ankle joint position sense; 30° and 45° of knee flexion were used for knee joint position sense assesment. Average absolute error for the dominant limb quantifed joint-position sense. Results : At the end of 4 weeks dynamic balance training program centered on the use of unstable surface, absolute error score for ankle inversion at 10° improved from 2.29±1.61 to 2.09±1.86, knee flexion at 30° improved from 5.07±2.78 to 4.80±2.55, and knee flexion at 45° improved from 4.12±2.19 to 3.87±2.25. However, this improvements were not significant (p>0.05) Conclusion: There were improvements noted (absolute error decreased for 10 o of inversion and 30 o and 45 o of knee flexion) despite the lack of significant differences and small effect sizes with 95% CIs that crossed 0. The lack of a significant improvement in absolute errors scores could be due to methodological considerations, participant characteristics and/or a training volume dose response.