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Background: The COVID-19 pandemic has brought unprecedented challenges to the world, creating significant impact on people's lives and subjective wellbeing. While previous studies have shown that students' wellbeing and how they manage their emotions are critical to students' learning, less research has considered their specific impacts on student engagement in online learning. Aims: The aim of this study is to examine how students' subjective wellbeing and emotion regulation strategies (viz cognitive reappraisal and expressive suppression) are associated with student engagement in online learning during the pandemic. Sample: A total of 965 students from a university in China participated in the study. Methods: The data were collected online during the COVID-19 from March to July 2020, which included measures of wellbeing, emotion regulation strategies, and online learning engagement. Results: Structural equation modelling results showed that wellbeing was positively associated with both the use of reappraisal and suppression. Moreover, mediation analysis showed that reappraisal partially mediated the relationship between wellbeing and all types of online learning engagement (including cognitive, emotional and behavioural engagements). Conversely, suppression was found to have a small mediating effect between wellbeing and behavioural engagement of online learning only. No such effect was found on cognitive and emotional engagements. Conclusions: The findings provide evidence on the positive relationship between wellbeing and both the strategies of suppression and reappraisal during the pandemic. However, only reappraisal has positive impact on learning, suggesting the importance of effective regulation strategies on students' online engagement. Theoretical and practical implications of the findings are discussed.

Little is known about parents’ perceptions of school counselling in Hong Kong. We adopted an explanatory sequential mixed methods design to investigate Chinese and non-Chinese parents’ perceptions. In phase one, 287 parents in Hong Kong were surveyed. Results suggested that Chinese parents had a poorer understanding of counsellors’ roles, more negative perceptions of counselling, and were less likely to perceive counselling as beneficial than did non-Chinese parents. In phase two, we interviewed 27 parents. Our findings suggested that cultural stigma and school-related factors accounted for the findings of the phase one study. Schools may consider proactive engagement with parents, and establishing communication which is sensitive to cultural norms to promote a better understanding of and willingness to participate in counselling. [ABSTRACT FROM AUTHOR]

This study aims to investigate the changes in the mechanical properties of quadriceps muscle following a sub-maximal concentric-eccentric step- ping exercise protocol. Twenty-four untrained healthy subjects aged 21.9±0.55 years were asked to perform a 10-minute stepping exercise where the dominant leg worked eccentrically and the non-dominant leg worked concentrically at a rate of 15 cycles/min. The quadriceps isokinetic peak torque and the corresponding peak torque angle at angular velocity of 60°/sec, and muscle soreness were determined at baseline, immediately after, day 1 and day 2 after the exercise protocol. Repeated measures of ANOVA showed no change in the peak torque after the eccentric exercise and concentric exercise (p > 0.05). There was a significant shift in the peak torque angle to longer muscle lengths in the eccentrically-exercised leg immediately (65.6±2.21°) and on the following two days after exercise (day 1: 68.3±2.71°; day 2: 67.4±2.51°) when compared with baseline (61.4±1.55°, p<0.05). These features were not observed in the concentrically-exercised leg. Eccentric exercise produced a higher level of soreness than concentric exercise at day 1 and 2 after the protocol. Sub-maximal eccentric exercise could bring about changes in the muscle properties resulting in a shift in the angle-torque relationship to longer muscle length without significant force deficit. [ABSTRACT FROM AUTHOR]

Osteoporosis is a growing health problem in Asian women and it is expected that half of the world's hip fractures will occur in Asia in 50 years' time. As the use of hormonal replacement therapy (HRT) is extremely low in postmenopausal Asian women, nonhormonal agents will be more acceptable for the treatment and prevention of osteoporosis. The efficacy, tolerability, and acceptability of alendronate, an amino-bisphosphonate, for Asian women was evaluated in 70 osteoporotic southern Chinese women in a prospective, randomized, double-blind study. The subjects were randomized to receive either alendronate 10 mg daily or placebo, plus calcium supplementation 500 mg daily. The baseline L 1-4 and hip bone mineral density (BMD) were similar between both groups. At the end of 1 year, there was an increase of 5.8% in the lumbar spine BMD and 3.4% at the total hip with alendronate treatment when compared with baseline values (P < 0.001). Alendronate treatment for 1 year resulted in significant improvement in BMD at all sites measured when compared with placebo. There was also marked reduction in serum alkaline phosphatase (ALP) and urinary n-telopeptide (NTx) in the alendronate group when compared with the placebo group (ALP 25% versus 2%, NTx 75% versus 14%, both P < 0.005). The changes in ALP and NTx at 6 and 12 months correlated with the change in BMD at all sites measured at 1 year (P all <0.05). Alendronate was well tolerated and accepted, although two cases of gastric ulcer were reported. We conclude that alendronate is an effective and well-accepted agent for the treatment of osteoporosis in Asian women. [ABSTRACT FROM AUTHOR]

The association between PvuII polymorphisms of the estrogen receptor alpha (ERalpha) gene and total as well as regional bone mineral density (BMD) in healthy Chinese women (n = 182) was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), where P indicated the absence and p the presence of PvuII restriction sites. Subjects with PP genotype had significantly higher BMD at the thoracic spine and ribs (both P < 0.05) when compared with those with Pp and pp genotypes. Although PP genotype had slightly higher BMD values at the lumbar spine L2-L4 region and hip by 8% and 7%, respectively, the results failed to reach statistical significance. After adjusting for age, height, weight, and years since menopause, PP genotype had higher BMD at the left (P < 0.02) and right (P < 0.05) rib region but not at the thoracic spine (P = 0.056). Analyzing the premenopausal subjects alone (n = 64) revealed that subjects with PP genotype had higher adjusted BMD at the right rib region (P < 0.05). When only the postmenopausal women (n = 118) were analyzed, the adjusted BMD of the PP genotype at the thoracic spine was significantly higher (P < 0.05) than the other two groups. In conclusion, estrogen receptor gene has a role in determining bone mass but the clinical impact on its own is probably small. [ABSTRACT FROM AUTHOR]

This study evaluated the physiological demands and low back neuromuscular fatigue patterns following a daytime work shift of 21 female nurses working in geriatric wards. Subjects' heart rate (HR) at work was monitored for 8 h and surface electromyogram (EMG) of their back muscle was recorded during a 1-minute horizontal trunk holding test before and after work. Results showed that the nurses had heart rates exceeding 90 beats/min in 57% and 110 beats/min in 19% of their working hours. The EMG revealed a significant drop in initial median frequency (MF) (p = 0.04) and increase in negative slope of the MF/time plot (p<0.001) of the back muscle after work. These suggest that the muscles were fatigued after work. The nurses rated patient lifting, transfer and turning as most physically demanding, and these corresponded to the highest heart rates recorded. The physiological and neuromuscular strain on the nurses indicated that extreme care should be exercised at work, particularly towards the end of a work shift when the muscles have become fatigued. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate the self-perceived exertion level and an objective measurement of muscle fatigue on violin players before and after a training session. Fourteen professional violin players volunteered in this study. Surveillance study was used to investigate the demographic characteristics, instrument playing background, playing habits variables and factors associated with playing-related musculoskeletal complaints (PRMCs). The subjective rating of the training-induced exertion was evaluated by the Borg scale ratings of perceived exertion (RPE). Surface electromyography (EMG) was used to record the fatigue level of the upper trapezius muscles before and after a training session. Medium frequency (MF) of the EMG signals was used to document the fatigue rate of this muscle. Descriptive statistics revealed a 79% prevalence rate of PRMCs with neck and shoulder region accounting for 57.1% of the areas reported. On the self-perceived exertion level associated with the training session, results indicated a significant increase in fatigue level (p = 0.003) after the training session. Regression analysis and paired samples t-tests revealed no significant difference in the slopes of MF on both sides of trapezius muscle, before and after the training sessions. The disparity in the subjective perception with the objective findings indicated that the violinists' self-perceived exertion arises from multiple sources. The high prevalence of PRMCs in this profession warrants further ergonomic investigation of possible work-related risk factors. [ABSTRACT FROM AUTHOR]

Objectives: Few studies have investigated the link between diet and intrinsic capacity (IC), and the potential sex difference in such association. This study examined the association between dietary patterns and IC and its sub-domains in Chinese community-dwelling older adults., Design: Cross-sectional analysis using baseline data from the MrOs and MsOs study., Setting: Community., Participants: Chinese community-dwelling older adults aged ≥65 years in Hong Kong., Measurements: Dietary intake was assessed using a validated food frequency questionnaire and priori and posteriori dietary pattern scores were generated. IC including measures of cognitive, locomotor, vitality, sensory and psychological domains was assessed. Multiple logistic regression was performed to examine the associations between dietary pattern scores and the likelihood of greater IC and sub-domain scores with adjustment for sociodemographic and lifestyle factors., Results: Data of 3730 participants (aged 72.2±5.0 years, 50.4% men) was available. In men, higher Diet Quality Index-International (DQI-I) and Okinawan diet scores, and lower "meat-fish" pattern scores were associated with greater IC. A higher DQI-I score was associated with greater locomotion, whereas higher "snacks-drinks-milk products" pattern score was associated with a greater sensory function. In women, none of the dietary pattern scores was associated with IC. Higher DQI-I score, Mediterranean-DASH Intervention for Neurodegenerative Delay Diet (MIND) score and "vegetables-fruits" pattern score were associated with greater psychological function., Conclusion: Various dietary patterns were associated with greater IC and its sub-domains in Chinese community-dwelling older adults, and more associations were observed in men than women. Strategies to improve diet and IC should take sex differences into account., Competing Interests: The authors declare no conflicts of interest.

Objectives: The Global Leadership Initiative on Malnutrition (GLIM) has recently published criteria for classifying malnutrition. This study investigated the associations between malnutrition and adverse outcomes, and identified which component(s) of the GLIM criteria is/are risk factor(s) of adverse outcomes in Chinese older adults., Design: A prospective cohort study of Chinese older adults in a healthy ageing study., Setting: Participants' place of residence., Participants: Community-dwelling and institutionalized Chinese older adults aged ≥70 years living in Hong Kong., Measurements: Malnutrition at baseline was classified according to selected GLIM criteria. Adverse outcomes including poor self-rated health, functional limitation (Barthel Index), falls, frailty (FRAIL scale), hospitalization and mortality were assessed after a 3-year follow-up. Associations between malnutrition and components of selected GLIM criteria (weight loss, low body mass index (BMI), low muscle mass and disease burden) and each adverse outcome were examined using adjusted binary logistic regression and Cox proportional hazards model. Odds ratio (OR) or hazard ratio (HR) and 95% confidence interval (CI) are presented., Results: Data of 1576 community-dwelling (45.5% female, 78.1±6.5 years) and 427 institutionalized (69.6% female, 85.5±6.4 years) older adults were included at baseline. Among community-dwelling older adults, malnutrition was associated with frailty (n=899, OR: 2.44, 95% CI: 1.05-5.70) and mortality (n=1007, HR: 1.37, 95% CI: 1.12-1.66). No association was found for other outcomes. Among institutionalized older adults, malnutrition was not associated with any outcomes. Low BMI and low muscle mass were risk factors of frailty; while weight loss was a risk factor of mortality in community-dwelling older adults. Weight loss and disease burden were risk factors of mortality among institutionalized older adults., Conclusion: The association between malnutrition and frailty and mortality was observed in community but not in institutional settings. Further studies are required to draw more definitive conclusions on the use of GLIM criteria in institutional settings., Competing Interests: The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

Competing Interests: The authors declare no conflicts of interest.

Objectives: Evidence on the topic regarding fruit and vegetable (FV) variety and health outcomes among older adults is limited. This study explored the prospective association of fruit variety, vegetable variety and combined FV variety with the risk of sarcopenia, frailty, all-cause and cause-specific mortality in community-dwelling Chinese older adults., Design: Prospective cohort study., Setting: Community., Participants: Community-dwelling Chinese older adults aged ≥65 years in Hong Kong., Measurements: Fruit variety, vegetable variety and combined FV variety at baseline were assessed using a validated food frequency questionnaire and the variety scores were stratified into tertiles. Sarcopenia (Asian Working Group for Sarcopenia 2019), frailty (Cardiovascular Health Study) and all-cause and cause-specific mortality (retrieved from an official database) were assessed at 14-year follow-up. Adjusted binary logistic regression or Cox proportional hazards model were performed to examine the association of fruit variety, vegetable variety and combined FV variety with each health outcome. Data are presented as hazard ratios (HRs) and 95% confidence intervals (CIs)., Results: Baseline dietary data of 3992 participants (median age: 72 years (interquartile range: 68-76), 49.9% women) was available. There were 436 and 371 participants who were newly identified as having sarcopenia and frailty respectively, and 1654 all-cause mortality, 367 cardiovascular diseases (CVD) mortality and 534 cancer mortality over 14-year. Tertiles of fruit variety, vegetable variety and combined FV variety were not associated with sarcopenia, frailty, CVD mortality and cancer mortality. Participants in the highest tertile of fruit variety (HR 0.81, 95% CI 0.70-0.95, p-trend 0.010), vegetable variety (HR 0.77, 95% CI 0.67-0.89, p-trend <0.001) and combined FV variety (HR 0.77, 95% CI 0.67-0.89. p-trend <0.001) showed lower risk of all-cause mortality compared with participants in the lowest tertile., Conclusion: Among community-dwelling Chinese older adults, FV variety was not associated with sarcopenia, frailty, CVD mortality and cancer mortality over 14-year. Higher fruit variety, vegetable variety and combined FV variety were associated with a lower risk of all-cause mortality. Promoting a wide FV variety might be recommended to benefit the health and longevity of this population., Competing Interests: The authors declare no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

Knee osteoarthritis is one of the most common degenerative diseases causing disability in elderly patients. Osteoarthritis is an increasing problem for ageing populations, such as that in Hong Kong. It is important for guidelines to be kept up to date with the best evidence-based osteoarthritis management practices available. The aim of this study was to review the current literature and international guidelines on non-surgical treatments for knee osteoarthritis and compared these with the current guidelines in Hong Kong, which were proposed in 2005. Internationally, exercise programmes for non-surgical management of osteoarthritis have been proven effective, and a pilot programme in Hong Kong for comprehensive non-surgical knee osteoarthritis management has been successful. Long-term studies on the effectiveness of such exercise programmes are required, to inform future changes to guidelines on osteoarthritis management., Competing Interests: No conflicts of interest are declared by the authors.

Aim: This study aimed to investigate the neuromuscular adaptation following a 5-week high frequency and low amplitude whole body vibration (WBV) exercise training., Methods: The study is a prospective, double blind, randomized controlled intervention design with a total of 19 subjects volunteered to participate in the study. They were randomly assigned either to WBV exercise training or control group. Both groups participated in a 5-week training program. The intervention group received WBV in semi-squat position on a device with an amplitude of 0.76 mm, frequency of 40Hz, and peak acceleration of 23.9 m/s2. Each vibration training session consisted of 6 series of 60s on with 30s rest period in between. The control group underwent the same statically mini-squatting position without exposure to WBV. The effectiveness of the vibration program was evaluated by vertical jump test and the isokinetic knee extensor peak torque. The possible neural factors that contributed to the improved muscular performance were evaluated by the stretch induced knee jerk reflex., Results: WBV training significantly enhanced the isokinetic knee extensor peak torque performance. Two-way mixed repeated measures analysis of variance revealed significant time effect of the changes in the peak torque (P=0.043) and the effect was significantly different between the intervention and control group (P=0.042). WBV did not affect vertical jump height, reflex latency of VL, EMGVL, and knee jerk angle., Conclusion: The results of this study do not support the hypothesis that the improvement in the muscular performance when subjects exposed to WBV training is attributed by neuromuscular efficiency via modulation of the muscle spindle sensitivity.

This study was to investigate the motor functional recovery process in chronic stroke during robot-assisted wrist training. Fifteen subjects with chronic upper extremity paresis after stroke attended a 20-session wrist tracking training using an interactive rehabilitation robot. Electromyographic (EMG) parameters, i.e., EMG activation levels of four muscles: biceps brachii (BIC), triceps brachii (TRI, lateral head), flexor carpiradialis (FCR), and extensor carpiradialis (ECR) and their co-contraction indexes (CI) were used to monitor the neuromuscular changes during the training course. The EMG activation levels of the FCR (11.1% of decrease from the initial), BIC (17.1% of decrease from the initial), and ECR (29.4% of decrease from the initial) muscles decreased significantly during the training (P<0.05). Such decrease was associated with decreased Modified Ashworth Scores for both the wrist and elbow joints (P<0.05). Significant decrease (P<0.05) was also found in CIs of muscle pairs, BIC&TRI (21% of decrease from the initial), FCR&BIC (11.3% of decrease from the initial), ECR&BIC (49.3% of decrease from the initial). The decreased CIs related to the BIC muscle were mainly caused by the reduction in the BIC EMG activation level, suggesting a better isolation of the wrist movements from the elbow motions. The decreased CI of ECR& FCR in the later training sessions (P<0.05) was due to the reduced co-contraction phase of the antagonist muscle pair in the tracking tasks. Significant improvements (P<0.05) were also found in motor outcomes related to the shoulder/elbow and wrist/hand scores assessed by the Fugl-Meyer assessment before and after the training. According to the evolution of the EMG parameters along the training course, further motor improvements could be obtained by providing more training sessions, since the decreases of the EMG parameters did not reach a steady state before the end of the training. The results in this study provided an objective and quantitative EMG measure to describe the motor recovery process during poststroke robot-assisted wrist for the further understanding on the neuromuscular mechanism associated with the recovery.

Aim: The aim of this study was to determine different variables leading to a successful completion of a 100-km ultradistance team event., Methods: Regular physical activity patterns, self-perceptions of fitness level and physical fitness profile were determined in subjects (n=253) registered for Trailwalker 2000. The battery of fitness tests included cardiopulmonary fitness, flexibility, muscular strength, muscular endurance and body fat composition., Results: The physical fitness data reveals that the subjects in this study have an above average fitness level compared with the norm. There was association of self-perceived fitness with physical fitness parameters (P=0) and significant correlation of the total fitness score with the completion time (P=0.02). More importantly, the team member with the lowest fitness total score was correlated with the finish time at the event (P=0). Logistic regression model identified that total fitness score and years of experience in Trailwalker were predictive of a successful completion in the event (r=0.37; P=0.007). However, the low variance suggested that the selected physical fitness tests have low prediction sensitivity to characterize the specific population in the study., Conclusions: There is a strong need to determine a combination of physical fitness tests that could accurately predict the performance of participants in the Trailwalker event.

Animal studies demonstrated that phytoestrogen had a protective effect against bone loss after ovariectomy. However, data on dietary phytoestrogen intake as well as its relationship with bone mineral density (BMD) in human are not available. Six hundred fifty southern Chinese women, aged 19 to 86 yr, were recruited to determine their dietary phytoestrogen intake by a food frequency questionnaire. BMDs at the lumbar spine and hip region were measured using dual energy x-ray absorptiometry. The subjects were analyzed according to various tertiles of phytoestrogen intake. Among the postmenopausal women (n = 357), significant differences in the lumbar spine (L2-4) BMD (0.820 +/- 0.145 vs. 0.771 +/- 0.131 g/cm2, P < 0.05) and Ward's triangle BMD (0.450 +/- 0.151 vs. 0.415 +/- 0.142 g/cm2; P < 0.05) were found between the highest and lowest intake of isoflavone after adjusting for age, height, weight, years since menopause, smoking, alcohol consumption, HRT usage, and daily calcium intake. Women with the highest intake of isoflavone had significantly lower levels of serum PTH (19.38 +/- 14.61 vs. 26.56 +/- 11.19 pg/ml; P < 0.05), osteocalcin (4.95 +/- 3.61 vs. 6.69 +/- 5.05 mg/liter; P = 0.05), and urinary N-telopeptide (34.18 +/- 25.31 vs. 49.66 +/- 41.00 nmol bone collagen equivalents/mmol creatinine; P < 0.05) when compared with those with the lowest intake of isoflavone. No association between dietary phytoestrogen intake and BMDs was seen in the premenopausal women with high endogenous E (n = 293). In conclusion, postmenopausal women with habitually high intake of dietary isoflavone are associated with higher BMD values at both the spine and hip region. Customarily high isoflavone intake may help to reverse the state of secondary hyperparathyroidism associated with E withdrawal and hence lower the rate of bone turnover in postmenopausal women.

Background: To investigate if the characteristics and training profiles of runners are significant indicators to predict a successful completion of a marathon., Experimental Design: comparative investigation between two groups of runners at a marathon race., Setting: participants of the study came from the 1998 Standard Chartered New Airport International Marathon in Hong Kong., Participants: 113 runners were investigated, of which 58 runners dropped out at the first 10 km of the race, while the other 55 were those that consulted for physiotherapy service after the marathon., Measures: using questionnaire, the characteristics and the training profiles of these runners were obtained. These included weekly training distance, longest and shortest training distance per session in one week; warm-up and stretching exercise with the training sessions, number of marathons previously finished and the runners' opinion of optimal training mileage to complete a marathon., Results: Independent t-tests with Bonferroni adjustment were used to investigate the difference between the two groups, the results showed significant difference in the weekly training distance (p=0.00), longest and shortest training distance per week (p=0.00), and personal opinion on optimal weekly training distance for a marathon (p=0.00). Logistic regression modeling was then employed to determine variables that best predict the likelihood of completing a marathon., Conclusions: The findings indicate that the non-finishers are poorly prepared and the results also identify that the longest mileage covered per training session is the best predictor for a successful completion of a marathon with an odds of 1.21.

The effects of different knee joint angles and fatigue on the neuromuscular control of the vastus medialis oblique (VMO) and vastus lateralis (VL) muscles were investigated in 17 (11 men, 6 women) young subjects. The electromyogram (EMG) activities and the force generation capacities were monitored before and after a fatigue protocol at three different knee joint angles, 90 degrees, 150 degrees, 175 degrees of knee extension, on three occasions. In response to randomly triggered light signals, the subjects performed three isometric maximal voluntary contraction (IMVC) that lasted for 4 to 8 s. This was then followed by the fatigue protocol which consisted of six bursts of contractions fixed at 30 s on and 10 s off. Immediately after the exercise to fatigue, the subjects performed another three IMVC in response to the light signals. Repeated measures ANOVA were performed to examine the effects of fatigue at these three positions on the electromechanical delay (EMD), median frequency (fmed), peak force (Fpeak) and root mean square (rms)-EMG:Fpeak quotient of VMO and VL. The results revealed a significant effect of the three knee joint angles on the EMD before the fatigue (P < 0.05). The fatigue protocol induced a significant decrease in Fpeak at all the three positions (P < 0.01). However, the fatigue induced a significant decrease of fmed at only 90 degrees and 150 degrees of knee extension (P < 0.01). This occurred in parallel with the lengthening of EMD at these two joint angles (P < 0.01 and P < 0.05). The effects of fatigue on the fmed and EMD were not significant between VMO and VL at all three angles. The insignificant difference in fmed and EMD between VMO and VL at the three knee positions before and after fatigue indicated that no preferential onset activation between VMO and VL had occurred.

Background: Overuse musculoskeletal injuries occur frequently in runners. Suggestions for prevention have focused on stretching exercises, modifying training schedules and the use of protective devices such as braces and insoles. To date, no systematic analysis of the literature on the effectiveness of these strategies in the prevention of overuse injuries has been published., Objectives: The objective of the review was to evaluate the evidence from randomised controlled trials on the prevention of lower limb soft-tissue running injuries., Search Strategy: An electronic database search included The Cochrane Musculoskeletal Injuries Group specialised register (date of last search October 2000), The Cochrane Controlled Trials Register (The Cochrane Library, Issue 3, 1999), MEDLINE (from 1966), EMBASE (from 1980), SPORT Discus (1975-2000), HERACLES (1975-2000), ATLANTES (1980-1996), BIOSIS, CINAHL, SCISEARCH, Current Contents, Index To Theses and Dissertation Abstracts. Date of last search for these databses: May 2000., Selection Criteria: Any randomised or quasi-randomised trials evaluating interventions to prevent lower limb soft-tissue running injuries., Data Collection and Analysis: All trials fulfilling the selection criteria were assessed by two reviewers independently. Data were also extracted independently by the two reviewers using a pre-derived data extraction form. Exploratory analyses, including pooling of results from groups of trials of similar designs were undertaken, using a fixed effects model. Results were reported as relative risks (RR) with 95 per cent confidence intervals (95% CI)., Main Results: Twelve trials with 8,806 participants were included. In one trial, a single control group was matched to three different included intervention groups. The effectiveness of stretching exercises (5 trials, 1944 participants in the intervention groups, 3159 controls), and of insoles and footwear modification (5 trials, 903 participants in the intervention groups, 3006 controls) in the prevention of lower extremity soft tissue injuries associated with running is unknown. Reducing the distance, frequency and duration of running may be effective in the prevention of lower extremity soft tissue injuries associated with running (3 trials, 514 participants in intervention groups, 1663 controls). Wearing a knee brace with a patellar support ring may be effective in the prevention of running-associated anterior knee pain (1 trial, 27 participants in the intervention group, 33 controls)., Reviewer's Conclusions: This review provides some evidence for the effectiveness of the modification of training schedules, but there is insufficient evidence to determine the effectiveness of stretching exercises for major lower limb muscle groups in reducing lower limb soft-tissue running injuries. More studies are required to confirm that knee braces may prevent knee pain, to clarify the role of stretching, and to quantify optimal training loads. Generalisability of the results may be limited by the intensive nature of military training (the context for most of the studies) and the inclusion of only small numbers of women.

Objective: To study the effect of chronic steroid therapy on bone mineral density (BMD) in premenopausal women with normal menstrual cycles and its treatment., Methods: A double blind placebo controlled study to evaluate 81 premenopausal women with systemic lupus erythematosus (SLE), aged 31.1 +/- 6 years, taking chronic steroid therapy, with a mean cumulative prednisone dose of 28 +/- 16.2 g. They were randomly allocated to 3 groups: Group 1: 0.5 microg calcitriol and 1200 mg calcium daily; Group 2: 1,200 mg calcium and placebo calcitriol; and Group 3: both placebo calcitriol and placebo calcium., Results: Baseline T score at the lumbar spine was > -1 in 56.8% and < -2.5 in 3.7% of the patients. At the end of 2 years, patients in the calcitriol group exhibited a significant increase of 2.1 +/- 2.4% in BMD at the lumbar spine compared to baseline value (p < 0.05). This change was not significantly different from the respective change in either calcium or placebo group (0.4 +/- 2.9% and 0.3 +/- 3.5%, respectively). No significant changes were observed in any treatment group in BMD at the hip or radius. Alkaline phosphatase increased both in the placebo (baseline: 57.5 +/- 17.5 IU/I; year 2: 60.9 +/- 15.3 IU/A) and the calcium group (baseline: 53.6 +/- 16.6 IU/I; year 2: 59.0 +/- 22.8 IU/1), but this increase reached statistical significance only in the calcium group, while the same variable remained stable in the calcitriol group (baseline: 53.9 +/- 14.1 IU/I; year 2: 54.6 +/- 12.3 IU/I)., Conclusion: Premenopausal women with SLE taking prolonged steroid therapy had lower BMD but showed no significant bone loss over the 2 year study period. The beneficial effect of calcitriol treatment in these premenopausal women was small, at least when it was instituted late in the course of steroid therapy.

Background and Purpose: Manual lifting is a frequent cause of back injury, and there is no evidence as to which training mode can provide the best training effect for lifting performance and muscle force. The purpose of this study was to examine the effects of a squat lift training and a free weight muscle training program on the maximum lifting load and isokinetic peak torque in subjects without known neuromuscular or musculoskeletal impairments., Subjects: Thirty-six adults (20 male, 16 female) without known neuromuscular or musculoskeletal impairments participated. The subjects' mean age was 21.25 years (SD=1.16, range=20-24)., Methods: Subjects were divided into 3 groups. Subjects in group 1 (n=12) performed squat lift training. Subjects in group 2 (n=12) participated in free weight resistance training of their shoulder abductors, elbow flexors, knee extensors and trunk extensors. Subjects in group 3 (n=12) served as controls. The maximum lifting load and isokinetic peak torques of the trunk extensors, knee extensors, elbow flexors, and shoulder abductors of each subject were measured before and after the study. Training was conducted on alternate days for 4 weeks, with an initial load of 80% of each subject's maximum capacity and with the load increased by 5% weekly., Results: All groups were comparable for all measured variables before the study. After 4 weeks, subjects in groups 1 and 2 demonstrated more improvement in maximum lifting load and isokinetic peak torque of the back extensors compared with the subjects in group 3, but the 2 training groups were not different., Conclusion and Discussion: The findings demonstrate that both squat lift and free weight resistance training are equally effective in improving the lifting load and isokinetic back extension performance of individuals without impairments.

The effects of muscle fatigue on the temporal neuromuscular control of the vastus medialis (VM) muscle were investigated in 19 young male subjects. The electromyogram (EMG) activities of VM and the force generation capacities of the quadriceps muscle were monitored before and after a fatigue protocol. In response to light signals, which were triggered randomly, the subjects made three maximal isometric knee extensions. This was then followed by the fatigue protocol which consisted of 30 isometric maximal voluntary contractions at a sequence of 5-s on and 5-s off. Immediately after the exercise to fatigue, the subjects performed another three maximal isometric contractions in response to the light signals. The effects of fatigue on the temporal neuromuscular control were then investigated by dividing the total reaction time (TRT) into premotor time (PMT) and electromechanical delay (EMD). The TRT was defined as the time interval between the light signal and the onset of the knee extension force. The PMT was defined as the time from the light signal to the onset of EMG activities of VM, and EMD as the time interval between onset of EMG activities to that of force generation. Following the contractions to fatigue there was a significant decrease in peak force (Fpeak, P = 0.016), an increase in the root mean square (rms)-EMG: Fpeak quotient (P = 0.001) but an insignificant change in the median frequency (P = 0.062) and rms-EMG (P = 0.119). Significant lengthening of mean EMD was found after the fatigue protocol [0.0396 (SD 0.009) vs. 0.0518 (SD 0.016) s P<0.001]. The lengthening of EMD in VM would affect the stabilizing effect of the patella during knee extension. The faster mean PMT [0.2445 (SD 0.093) vs. 0.2075 (SD 0.074) s, P = 0.042] following the fatigue protocol might have compensated for the lengthened EMD and contributed to the insignificant change in the mean TRT [0.284 (SD 0.09) vs. 0.259 (SD 0.073) s, P = 0.164]. This was probably related to the low level of fatigue (15% decrease in force) and the stereotyped nature of the action such that the effects of the fatigue on neuromuscular control were likely to have been attributable to peripheral processes.

The need for a means of antenatal diagnosis of chromosomal abnormalities in the last trimester of pregnancy to avoid unnecessary intervention for the sake of the fetus is illustrated by a case in which polyhydramnios and suspected fetal hydrocephalus were found by ultrasound at 36 weeks gestation. The mother decided against early caesarian section for possible neurosurgery for the fetus. Later, she delivered vaginally of a baby with multiple abnormalities and trisomy 18.