A Study on the Effects of Instability Resistance Training on Dynamic Balance and Rapid Change-of-Direction Ability in College Basketball Recruits

All participants completed a 12-week training program, training three times per week with at least a 48-hour interval between consecutive training sessions. Depending on their group assignment, participants performed either unstable resistance training (experimental group) or traditional resistance training on a stable surface (control group). Both groups followed the same training frequency, training volume, exercise sequence, and rest intervals between sets; the only difference was the training surface. During training, the experimental group used unstable equipment such as BOSU balls, balance pads, and Swiss balls, while the control group performed the corresponding exercises on a stable floor. All training sessions were uniformly supervised by researchers to ensure proper form and training adherence.

Each training session began with a standardized warm-up, including 5 minutes of light jogging and dynamic stretching, followed by exercise-specific warm-up movements. Prior to the formal training, participants completed one set of adaptation exercises at approximately 50% of the formal training load. Rest periods between exercises were 30 seconds, while rest periods between sets were controlled at 45-60 seconds depending on the training phase.

The experimental group's training program was divided into three cycles. Weeks 1 through 4 constituted the basic adaptation phase, with training consisting of BOSU ball elbow plank (40 s × 4 sets), squats on a balance pad (10 reps × 4 sets), back-against-Swiss-ball squats with ball between the knees (40 s × 4 sets), and swan-pose balance on the BOSU ball (30 s × 4 sets), with 45 s of rest between sets. Weeks 5 through 8 constitute the enhancement phase, with training consisting of weighted squats on a balance pad (15 reps × 4 sets), weighted deadlifts on a balance pad (10 reps × 4 sets), alternating lunges on a BOSU ball (15 reps × 4 sets), and medicine ball lunge twists with toss and catch (with the front leg on the BOSU ball) (12 reps × 4 sets), with a 45-second rest between sets. Weeks 9 through 12 constitute the consolidation phase, with training consisting of weighted single-leg deadlifts on a balance pad (12 reps × 4 sets), weighted crunches on a BOSU ball (12 reps × 4 sets), weighted Russian twists on the BOSU ball (12 reps × 4 sets), and weighted Bulgarian split squats on the BOSU ball (12 reps × 4 sets), with 60 s of rest between sets.

The control group underwent traditional resistance training on a stable surface, with the same training cycle and training volume as the experimental group. Weeks 1 through 4 consisted of elbow plank (40 s × 4 sets), single-leg lifts on a flat surface (10 reps × 4 sets), static squats with a ball held against a wall (40 s × 4 sets), and swan pose balance on the floor (30 s × 4 sets); Weeks 5 through 8: squats (15 reps × 4 sets), weighted single-leg lifts (10 reps × 4 sets), weighted alternating lunges (15 reps × 4 sets), and medicine ball lunge twists with toss and catch (12 reps × 4 sets); Weeks 9 through 12 consisted of weighted squats (12 reps × 4 sets), weighted crunches (12 reps × 4 sets), weighted Russian twists (12 reps × 4 sets), and weighted Bulgarian split squats (12 reps × 4 sets), with rest intervals of 45 s and 60 s between sets, respectively. The experimental instruments and their models used during the experiment were as follows: stopwatch (PC2810, China), measuring tape (JGW-5m, China) , a whistle (PE-001, China), marker cones (KS-TC23, China), a Y Balance Test Kit™ (USA), a BOSU ball (SH-BOSU58, China), a balance mat (SH-BP34, China), 5 kg dumbbells (SH-DB5, China), a 5 kg medicine ball (SH-MB5, China), barbell plates (SH-WP5, China), and 65 cm Swiss balls (SH-GB65, China).