Effects of participation in an eight-week, online video body-weight resistance training on cognitive function and physical fitness in older adults: A randomized control trial.

The purpose of this study was to investigate the effects of an eight-week online video bodyweight resistance training on cognitive function and physical fitness in older adults. A total of 30 older adults was randomly assigned into either an exercise group or a control group. The exercise group participated in the exercise and the control group was required to maintain daily living. Mini mental status examination (MMSE) and senior fit-ness tests (SFT) were measured pre- and post-eight weeks of intervention. Participating in the exercise experienced increases in cognitive functions of attention (p < 0.05) and calculation (p < 0.05), recall (p < 0.05), and repetition (p < 0.05) from the MMSE. Also, older adults in the exercise group demonstrated improved two-minute walk (p < 0.05), chair sit tests (p < 0.05), and results of the SFT. The online video resistance training may help to increase cognitive function and fitness in older adults.

Prevalence of sports injuries in Korean fencers aged 14-40 years.

BACKGROUND: Although sites and types of injury frequently occurring in fencers have been well described, the type of injury caused by the use of fencing movements is still unknown. This study aimed to provide basic data for injury prevention by understanding the sports injury status in fencers. METHODS: A total of 584 South Korean fencers were included in the survey and were classified according to the injured site, cause of injury, and movement that causes injury. The collected data were analyzed using frequency analysis, χ2 tests, and logistic regression analysis to identify differences in sex, event type, age, and career. RESULTS: Female (P=0.001) and foil fencers (P=0.015) were more likely to experience injury than male and sabre and epee fencers. The incidence of injury was significantly higher according to age (P=0.001) and career (P=0.001). The ankle was the most frequently injured site (17.71%). Injuries most frequently occur during Fente movement (48.11%). Insufficient warm-up was the most common cause of injury (23.91%) in all groups. CONCLUSIONS: These results suggest that a specific warm-up program and strengthening exercises of the ankle and knee ligaments should be established to prevent injuries for fencers. Particularly, female, foil, adult, and experienced fencers should be more careful in preventing injuries.

Fourier-Based Footfall Placement Variability in Parkinson's Disease.

The current investigation examined whether Parkinson's patients (PD) have greater Fourier-based footfall placement gait with the greatest mobility dysfunction variability (FPV) than the age and gender matched control group and that variability would be the greatest in the PD participants with the greatest mobility dysfunction indexed Hoehn/Yahr scale. 35 persons undergoing PD and 30 age-matched controls participated in this investigation. Participants repeated two trials' normal walking and average and variability parameters of gait were measured using a 3.66 m electronic walkway. FPV was quantified as a change in the center of pressure during gait. Persons with PD were divided into two groups based on Hoehn/Yahr scale. Overall, persons with PD had smaller average performance indexed by mean and greater gait variability than controls as indexed by CV and Fourier-based variability (p's<0.05). Moreover, PD with higher mobility dysfunction had not only greater variability in traditional parameters but also greater Fourier-based variability than nonfallers with MS (p<.001) with higher effect size (η 2=0.37 vs.0.18-0.29). These observations highlight the fact that footfall placement variability is related to mobility dysfunction in PD. Further study is necessary to determine contributing factors to an increased FPV and whether targeted interventions such as exercise can reduce FPV.

Comparative gait analysis between children with autism and age-matched controls: analysis with temporal-spatial and foot pressure variables.

[Purpose] The purpose of this study was to investigate the gait pattern of children with autism by using a gait analysis system. [Subjects] Thirty children were selected for this study: 15 with autism (age, 11.2 ± 2.8 years; weight, 48.1 ± 14.1 kg; height, 1.51 ± 0.11 m) and 15 healthy age-matched controls (age, 11.0 ± 2.9 years; weight, 43.6 ± 10 kg; height, 1.51 ± 0.011 m). [Methods] All participants walked three times on the GAITRite(®) system while their plantar pressure was being recorded. [Results] The results showed a reduction in cadence, gait velocity, and step length, and an increase in step width in children with autism. Plantar pressure variables highlight the differences between the active pressure areas, especially in the hindfoot of children with autism. [Conclusion] The results suggest that children with autism have an abnormal gait compared with that of age-matched controls, and thus they need extra attention to correct these abnormal gait patterns.

Biomechanical comparison of rotational activities between anterior cruciate ligament- and posterior cruciate ligament-reconstructed patients.

PURPOSE: The purpose of this study was to compare the early functional recovery using biomechanical properties between anterior cruciate ligament (ACL)- and posterior cruciate ligament (PCL)-reconstructed patients and to determine the biomechanical deficit of PCL-reconstructed patients compared to ACL-reconstructed patients. METHODS: A motion analysis system was used to measure and calculate kinematic and kinetic data for 10 patients who underwent PCL-reconstructed patients [experimental group (group 1)], 10 ACL-reconstructed patients (group 2), and 10 healthy subjects (group 3) during 45°, 90°, 135°, and 180° cutting and turn running tasks. Groups 1 and 2 were assessed at 3 (return to daily activity) and 6 months (return to light sports) postoperatively. RESULTS: At 3 months postoperatively, compared to groups 2 and 3, group 1 showed a decrease in knee flexion angle, extension moment, valgus moment, external rotational moment, ground reaction force, and increased hamstring-quadriceps ratio. At 6 months postoperatively, results from group 1 resembled those of groups 2 and 3 over time. CONCLUSIONS: Patients who underwent PCL reconstruction showed some biomechanical deficits in performance of activities requiring rotation, compared to those who underwent ACL reconstruction. Therefore, the modification of a rehabilitation programme for patients who underwent PCL reconstruction would be necessary for improvement of the biomechanical properties during performance of dynamic activities. LEVEL OF EVIDENCE: Case-control study, Level III.

Effects of menarcheal age on the anterior cruciate ligament injury risk factors during single-legged drop landing in female artistic elite gymnasts.

INTRODUCTION: Although numerous studies have demonstrated the relationship between maturation and lower extremity biomechanics during landing in team sport athletes, we are presently uninformed of any research that examined the single-legged drop landing biomechanics of gymnasts. The purpose of this study is to investigate the effects of the menarcheal age on the lower extremity biomechanics during a single-legged drop landing in female artistic elite gymnasts. MATERIALS AND METHODS: Twenty-two female artistic elite gymnasts, between 9 and 36 years of age, participated in this study. The participants were divided into two groups pre- (n = 11) and post- (n = 11) menarche and asked to perform a single-legged drop landing on top of a 30 cm platform and land on a force plate. The statistical analysis consisted of the multivariate analysis with the level of significance set at p < 0.05. RESULTS: The post-menarche group showed a decrease in their maximum knee flexion angle and increase in their maximum knee abduction angle, maximum internal tibial rotation angle, maximum knee abduction moment, and hamstring-quadriceps muscle activity ratio compared with the pre-menarche group during the single-legged drop landing. CONCLUSIONS: The post-menarche group showed an increased noncontact anterior cruciate ligament injury risk, due to their greater knee loads, compared with the pre-menarche group.

Serial assessment of knee joint moments in posterior cruciate ligament and posterolateral corner reconstructed patients during a turn running task.

INTRODUCTION: During post-operative rehabilitation for posterior cruciate ligament (PCL) reconstruction, flexion is limited to 90° for the first 6 weeks, and hamstring strengthening is initiated at 3 months because of static stability. The posterolateral corner sling (PLCS) procedure is frequently performed with PCL reconstruction to help alleviate posterolateral rotator instability, and it is possible, during this procedure, to damage the dynamic motion and to over-constrain the knee. MATERIALS AND METHODS: For the patients group, PCL and PLCS reconstructions were performed simultaneously, and all reconstructed patients had stable knees and showed no complications. A motion analysis system was used to measure and calculate kinematic and kinetic data for seven patients after PCL and PLCS reconstruction (patients group) and seven normal subjects (control group) during a turn running task. The study was conducted on two groups at both 3 months (return to daily activity) and 6 months (return to light sports) post-operation. At 6 months after surgery, the dial test was also performed to observe the static rotational stability. RESULTS: Compared to the control group, the patients group showed a decreased extension moment (-1.15 ± 0.46 vs. -3.51 ± 0.69 Nm/kg, p = 0.000), a decreased valgus moment (-1.36 ± 0.72 vs. -2.15 ± 0.54 Nm/kg, p = 0.041) and a decreased external rotational moment (-0.15 ± 0.11 vs. -0.37 ± 0.10 Nm/kg, p = 0.002) 3 months post-operatively. However, these results approximated to the normal control, and the patients group showed an improved extension moment (-2.95 ± 0.67 Nm/kg, p = 0.188), valgus moment (-1.73 ± 0.58 Nm/kg, p = 0.359) and external rotational moment (-0.30 ± 0.09 Nm/kg, p = 0.325) at 6 months post-operatively. A static rotational stability revealed a similar or over-constrained state compared with the contralateral knee, and no patient showed rotational instability. CONCLUSIONS: PCL-PLCS reconstructed patients were reluctant to engage in, or lacked strength for, daily rotational activities. Therefore, we must consider more active and systematic co-contraction exercise of the hamstring and quadriceps and rehabilitation program about rotation that is not adverse to the static stability in PCL-PLCS reconstructed patients for early return to daily activities.

A meta-analysis of the effect of neuromuscular training on the prevention of the anterior cruciate ligament injury in female athletes.

Female athletes are more prone to anterior cruciate ligament (ACL) injury than their male counterparts, presumably because of anatomical, hormonal, and neuromuscular differences. Of these three, only the neuromuscular component can be modified by preventive exercise. We aimed to evaluate the effect of a neuromuscular protocol on the prevention of ACL injury by performing meta-analysis, and to identify essential factors by subgroup analysis. An extensive literature review was conducted to identify relevant studies, and eventually, only seven randomized controlled trials or prospective cohort studies were included in the analysis. The odds ratios (OR) and the confidence interval (CI) for the overall effects of training and of potentially contributory factors were estimated. The OR and the 95% CI for the overall effect of the preventive training were 0.40 and [0.27, 0.60], respectively. Subgroup analysis revealed that an age under 18, soccer rather than handball, pre- and in-season training rather than either pre- or in-season training, and the plyometrics and strengthening components rather than balancing were significant. Meta-analysis showed that pre- and in-season neuromuscular training with an emphasis on plyometrics and strengthening exercises was effective at preventing ACL injury in female athletes, especially in those under 18 years of age. Further study is required to develop a relevant training program protocol of appropriate intensity.

Biomechanical evaluation of cross-pin versus interference screw tibial fixation using a soft-tissue graft during transtibial posterior cruciate ligament reconstruction.

PURPOSE: This article reports the biomechanical demonstration of a technique for transtibial posterior cruciate ligament (PCL) reconstruction using a soft-tissue graft with cross-pin fixation in the tibia and compares this with the biomechanical properties achieved with other methods. METHODS: We used 5 paired cadaveric knees and another 10 tibias. Soft-tissue grafts were randomized. The femoral side of the anterior cruciate ligament was fixed with a Bio-TransFix device (Arthrex, Naples, FL) (group I), and the tibial side of the PCL was fixed with a Bio-TransFix device (group II). In another 10 tibias, tibial fixations were performed by use of a bio-interference screw (group III). Biomechanical testing was carried out on a testing machine, and maximal failure load, stiffness, and displacement were analyzed. The lengths of the slots of the TransFix device (Arthrex) from the near cortex were measured to compare the proper length of the device. RESULTS: Maximal mean failure loads in groups I, II, and III were 549.3 +/- 55.4 N, 570.8 +/- 96.9 N, and 371.3 +/- 106.2 N, respectively, showing a significant difference (P = .0003). Stiffnesses were 47.52 +/- 16.84 N/mm, 59.14 +/- 17.09 N/mm, and 27.60 +/- 16.73 N/mm, respectively, showing a significant difference (P = .01). Mean displacements were 19.99 +/- 5.79 mm, 19.09 +/- 8.51 mm, and 17.58 +/- 7.10 mm, respectively, showing no significant difference (P = .7535). The mean lengths of the slots of the TransFix device of the femurs and tibias were similar at 20.3 +/- 1.25 mm and 20.2 +/- 1.32 mm, respectively, showing no significant difference (P = .8637). CONCLUSIONS: The transtibial technique by use of cross-pin tibial fixation with a Bio-TransFix device in PCL reconstruction provides stable fixation that is comparable to that achieved by use of conventional bio-interference screw fixation and femoral fixation in an anterior cruciate ligament reconstruction, an already well-established technique. CLINICAL RELEVANCE: Biomechanically, tibial cross-pin fixation compares favorably with interference screw fixation and is useful when a graft is short. However, safety issues have not yet been resolved.

Effects of sports injury prevention training on the biomechanical risk factors of anterior cruciate ligament injury in high school female basketball players.

BACKGROUND: Female athletes have a higher risk of anterior cruciate ligament injury than their male counterparts who play at similar levels in sports involving pivoting and landing. HYPOTHESIS: The competitive female basketball players who participated in a sports injury prevention training program would show better muscle strength and flexibility and improved biomechanical properties associated with anterior cruciate ligament injury than during the pretraining period and than posttraining parameters in a control group. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 22 high school female basketball players were recruited and randomly divided into 2 groups (the experimental group and the control group, 11 participants each). The experimental group was instructed in the 6 parts of the sports injury prevention training program and performed it during the first 20 minutes of team practice for the next 8 weeks, while the control group performed their regular training program. Both groups were tested with a rebound-jump task before and after the 8-week period. A total of 21 reflective markers were placed in preassigned positions. In this controlled laboratory study, a 2-way analysis of variance (2 x 2) experimental design was used for the statistical analysis (P < .05) using the experimental group and a testing session as within and between factors, respectively. Post hoc tests with Sidak correction were used when significant factor effects and/or interactions were observed. RESULTS: A comparison of the experimental group's pretraining and posttraining results identified training effects on all strength parameters (P = .004 to .043) and on knee flexion, which reflects increased flexibility (P = .022). The experimental group showed higher knee flexion angles (P = .024), greater interknee distances (P = .004), lower hamstring-quadriceps ratios (P = .023), and lower maximum knee extension torques (P = .043) after training. In the control group, no statistical differences were observed between pretraining and posttraining findings (P = .084 to .873). At pretraining, no significant differences were observed between the 2 groups for any parameter (P = .067 to .784). However, a comparison of the 2 groups after training revealed that the experimental group had significantly higher knee flexion angles (P = .023), greater knee distances (P = .005), lower hamstring-quadriceps ratios (P = .021), lower maximum knee extension torques (P = .124), and higher maximum knee abduction torques P (= .043) than the control group. CONCLUSION: The sports injury prevention training program improved the strength and flexibility of the competitive female basketball players tested and biomechanical properties associated with anterior cruciate ligament injury as compared with pretraining parameters and with posttraining parameters in the control group. CLINICAL RELEVANCE: This injury prevention program could potentially modify the flexibility, strength, and biomechanical properties associated with ACL injury and lower the athlete's risk for injury.