This study sought to identify kinetic and electromyographic subphase characteristics distinguishing good from poor jumpers during countermovement vertical jumps (CMVJs), as defined by the reactive strength index (RSI, CMVJ displacement divided by jump time; cutoff = 0.46 m·s). A total of 15 men (1.8 [0.6] m, 84.5 [8.5] kg, 24 [2] y) were stratified by RSI into good (n = 6; RSI = 0.57 [0.07] m·s) and poor (n = 9; RSI = 0.39 [0.06] m·s) performance groups. The following variables were compared between groups using independent t tests (α = .05) and Cohen's d effect sizes (d ≥ 0.8, large): jump height, propulsive impulse, eccentric rate of force development, and jump time, unloading, eccentric, and concentric subphase times, and average electromyographic amplitudes of 8 lower extremity muscles. Compared with the poor RSI group, the good RSI group exhibited a greater, though not statistically different CMVJ displacement (d = 1.07, P = .06). In addition, the good RSI group exhibited a significantly greater propulsive impulse (P = .04, d = 1.27) and a significantly more rapid unloading subphase (P = .04, d = 1.08). No other significant or noteworthy differences were detected. Enhanced RSI appears related to a quicker unloading phase, allowing a greater portion of the total jumping phase to be utilized generating positive net force. Poor jumpers should aim to use unloading strategies that emphasize quickness to enhance RSI during CMVJ.
Purpose: This study investigated the evolution of neuromotor control during a typical short sport-specific rehabilitation program (SSR) in professional soccer players who had incurred a major lower-limb injury ( = 15, chondral and muscle injuries, ACL-reconstruction).
Methods: All injured participants ( = 15) were in the on-field rehabilitation phase of their specific sport rehabilitation process, prior to return to play. An experimental group (EG, chondral and muscle injuries, ACL-reconstruction) followed a 3-week SSR-program composed of muscular and core strengthening (weightlifting, functional stability, explosivity and mobility exercises), running and cycling, neuromotor reprogramming, cognitive development and specific soccer on-field rehabilitation (acceleration, braking, cutting, dual-contact, high-speed-running, sprint, jump, drills with ball).
Background: To investigate the efficacy of three-compartment restriction spectrum imaging (RSI), diffusion kurtosis imaging (DKI), and diffusion-weighted imaging (DWI) in the assessment of lymph node metastases (LNM) in rectal cancer.
Methods: A total of 77 patients with rectal cancer who underwent pelvic MRI were enrolled. RSI-derived parameters (f, f, and f), DKI-derived parameters (D and K), and the DWI-derived parameter (ADC) were calculated and compared using a Mann-Whitney U test or independent samples t-test.
This study aimed to investigate the effects of plyometric (PT) or strength (ST) training on change of direction (COD) performance at two differing angles among highly trained youth footballers. Seventy-one national-level youth football players (14.6 ± 1.
Objective: To compare reflux symptoms, Zenker's diverticulum recurrence, and clinical outcomes in patients with and without a history of hiatal hernia who underwent Zenker's diverticulotomy (ZD).
Study Design: Single institution retrospective review.
Objective: This study compared the effects of Flywheel Resistance Squat Training (FRST) vs. Traditional Resistance Squat Training (TRST) on lower body strength in female collegiate basketball players.
Methods: Nineteen participants were randomly assigned to either the FRST group (n = 9) or the TRST group (n = 10) through a random number draw.
