Aldridgebaxter3901

BACKGROUND Regular physical activity is of paramount importance to reduce chronic disease risk. Classical ballet training requires balance, strength, and range of motion. Participation in social ballet classes is increasing. Ballet training interventions may be an alternative method of regular, enjoyable activity. This review aimed to determine the effectiveness of classical ballet training interventions on physical and psychological health. METHODS Ten databases were searched until April 2019. The included studies investigated classical ballet training interventions of a ≥4-week duration, on any population (no restrictions on experience and clinical condition), measuring physical health or psychological outcomes. RESULTS Twenty-three studies (25 intervention groups) were included, comprising experienced (19 groups) and novice dancers (6 groups). In experienced populations, muscular strength was the most commonly reported outcome. However, only 25% of these studies reported improvements. With novice dancers, including clinical populations, balance showed the most positive change, improving in 75% of studies that reported this measure. CONCLUSIONS Classical ballet training may improve balance in novices and maintain physical activity across the life span. Experienced dancers showed no further improvement, perhaps due to an already greater ability. There was large heterogeneity between the included studies. A greater focus on classical ballet interventions for inexperienced populations is required.CONTEXT Contemporary synthetic playing surfaces have been associated with an increased risk of ankle injury in the various types of football. Triaxial accelerometers facilitate in vivo assessment of planar mechanical loading on the player. OBJECTIVE To quantify the influence of playing surface on the PlayerLoad elicited during footwork and plyometric drills focused on the mechanism of ankle injury. DESIGN Repeated-measures, field-based design. SETTING Regulation soccer pitches. PARTICIPANTS A total of 15 amateur soccer players (22.1 [2.4] y), injury free with ≥6 years competitive experience. INTERVENTIONS Each player completed a test battery comprising 3 footwork drills (anterior, lateral, and diagonal) and 4 plyometric drills (anterior hop, inversion hop, eversion hop, and diagonal hop) on natural turf (NT), third-generation artificial turf (3G), and AstroTurf. Global positioning system sensors were located at C7 and the mid-tibia of each leg to measure triaxial acceleration (100 Hz). MAIN OUTCOME MEASURES PlayerLoad in each axial plane was calculated for each drill on each surface and at each global positioning system location. RESULTS Analysis of variance revealed a significant main effect for sensor location in all drills, with PlayerLoad higher at mid-tibia than at C7 in all movement planes. SN-011 ic50 AstroTurf elicited significantly higher PlayerLoad in the mediolateral and anteroposterior planes, with typically no difference between NT and 3G. In isolated inversion and eversion hopping trials, the 3G surface also elicited lower PlayerLoad than NT. CONCLUSIONS PlayerLoad magnitude was sensitive to unit placement, advocating measurement with greater anatomical relevance when using microelectromechanical systems technology to monitor training or rehabilitation load. AstroTurf elicited higher PlayerLoad across all planes and drills and should be avoided for rehabilitative purposes, whereas 3G elicited a similar mechanical response to NT.CONTEXT Clinically, it has been suggested that increased activation of intrinsic foot muscles may alter the demand of extrinsic muscle activity surrounding the ankle joint in patients with stage II posterior tibial tendon dysfunction. However, there is limited empirical evidence supporting this notion. OBJECTIVE The purpose of this study was to investigate the effects of a 4-week short-foot exercise (SFE) on biomechanical factors in patients with stage II posterior tibial tendon dysfunction. DESIGN Single-group pretest-posttest. SETTING University laboratory. PARTICIPANTS Fifteen subjects (8 males and 7 females) with stage II posterior tibial tendon dysfunction who had pain in posterior tibial tendon, pronated foot deformity (foot posture index ≥+6), and flexible foot deformity (navicular drop ≥10 mm) were voluntarily recruited. INTERVENTION All subjects completed a 4-week SFE program (15 repetitions × 5 sets/d and 3 d/wk) of 4 stages (standing with feedback, sitting, double-leg, and one-leg standing positionerior and fibularis longus muscles, although it could not influence their structural deformity and ankle joint moment. It could produce a potential benefit of decreased tibialis posterior activation.CONTEXT Despite significant emphasis on anterior cruciate ligament injury prevention, injury rates continue to rise and reinjury is common. Interventions to reduce injury have included resistance, balance, and jump training elements. The use of sand-based jump training has been postulated as an effective treatment. However, evidence on landing mechanics is limited. OBJECTIVE To determine potential differences in landing strategies and subsequent landing knee valgus when performing single-leg landing (SLL) and drop jump (DJ) tasks onto sand and land, and to compare between both male and female populations. DESIGN A randomized repeated-measures crossover design. SETTING University laboratory. PARTICIPANTS Thirty-one participants (20 males and 11 females) from a university population. INTERVENTIONS All participants completed DJ and SLL tasks on both sand and land surfaces. MAIN OUTCOME MEASURES Two-dimensional frontal plane projection angle (FPPA) of knee valgus was measured in both the DJ and SLL tasks (right and left) for both sand and land conditions. RESULTS FPPA was lower (moderate to large effect) for SLL in sand compared with land in both legs (left 4.3° [2.8°]; right 4.1° [3.8°]) for females. However, effects were unclear (left -0.7° [2.2°]) and trivial for males (right -1.1° [1.9°]). FPPA differences for males and females performing DJ were unclear; thus, more data is required. Differences in FPPA (land vs sand) with respect to grouping (sex) for both SLL left (4.9° [3.0°]) and right (5.1° [4.0°]) were very likely higher (small)/possibly moderate for females compared with males. CONCLUSIONS The effects of sand on FPPA during DJ tasks in males and females are unclear, and further data is required. However, the moderate to large reductions in FPPA in females during SLL tasks suggest that sand may provide a safer alternative to firm ground for female athletes in anterior cruciate ligament injury prevention and rehabilitation programs, which involve a SLL component.