Rope skipping increases bone mineral density at calcanei of pubertal girls in Hong Kong: A quasi-experimental investigation

Effects of Different Surfaces on Metabolic Cost During Repetitive Jumping: A Pilot Study

The purpose of this pilot study was to determine if there is a difference in metabolic cost when jumping on platforms of varying thickness, as well as whether a difference exists in metabolic cost between genders exists on the different platforms. Fourteen participants (seven males and seven females) completed three repetitive jumping trials on the DigiJump machine. Each trial was performed at a cadence of 120 jumps per minute and at a minimum height of 1/2″ per jump. Trials were completed on platforms of 1/2″, 3/8″, and 1/4″ thickness. Participants were instructed to jump as long as possible while maintaining the prescribed cadence or until fifteen minutes had elapsed. There were no differences observed in metabolic cost or exertion for all participants or between genders as indicated by oxygen consumption, respiratory exchange ratio, upper leg RPE, or lower leg RPE. There were also no differences for durations of exercise the participants were able to sustain on the machine. However, when comparing data between genders, a significant interaction was observed in total body RPE across the three platforms (p = .009) and in HR on the 1/2″ platform (p = .018). Results from this study indicate that metabolic cost is similar during repetitive jumping regardless of platform rigidity or gender. However, post-trial comments from participants did show preferences towards specific platforms, though this was not apparent in exercise duration.

The effect of weight-bearing exercise on the mechanisms of bone health in young females: A systematic review

Weight-bearing exercise (WBE) has been identified as an appropriate approach for increasing peak bone mass, however, there is a lack of specific physical activity recommendations in this area. Thus, the aim of this systematic review is to determine the optimal mode of WBE, specifically identifying the intensity, duration, frequency, and load, to elicit the optimal effect on bone mass in young females, aged 5-18. A literature search was conducted from the 28th of June to the 20th of July 2021 using PubMed/Medline, Web of Science and SPORTDiscus. The search produced 1405 results, of which 15 were deemed appropriate for inclusion. The majority of studies (n=12) found a significant positive effect for at least one bone measure through their respective WBE exposure (p<0.05). Bone mass accrual was found to be site-specific depending on WBE exposure type, load, and maturity status. Also, longitudinal effects on bone mass accrual were found exclusively in gymnastics participants, even if participation level decreased (i.e., retirement). The results of this study support the use of WBE to improve parameters of bone health. However, further research is needed as the optimal mode of WBE to elicit the optimal effect on bone mass is still unclear.

The Important Function and Training of Sensitive Quality in Basketball Method Research

Basketball is a skill-oriented group sport, which has been popularized and developed in China. However, the research on physical fitness training of basketball in China mostly focused on strength quality and speed quality, and less research was done on sensitive quality. Based on this, this paper aims to explore the important role of agility in basketball and put forward reasonable and scientific training suggestions in order to enrich the content of basketball training, complete the training system and to improve the level of basketball players as a whole.

Jump rope training effects on health- and sport-related physical fitness in young participants: A systematic review with meta-analysis

The aim of this systematic review with meta-analysis was to assess the available body of published peer-reviewed articles related on the effects of jump rope training (JRT) compared with active/passive controls on health- and sport-related physical fitness outcomes. Searches were conducted in three databases, including studies that satisfied the following criteria: i) healthy participants; ii) a JRT programprogramme; iii) active or traditional control group; iv) at least one measure related to health- and sport-related physical fitness; v) multi-arm trials. The random-effects model was used for the meta-analyses. Twenty-one moderate-high quality (i.e., PEDro scale) studies were meta-analysed, involving 1,021 participants (male, 50.4%). Eighteen studies included participants with a mean age <18 years old. The duration of the JRT interventions ranged from 6 to 40 weeks. Meta-analyses revealed improvements (i.e., p = 0.048 to <0.001; ES = 0.23-1.19; I² = 0.0-76.9%) in resting heart rate, body mass index, fat mass, cardiorespiratory endurance, lower- and upper-body maximal strength, jumping, range of motion, and sprinting. No significant JRT effects were noted for systolic-diastolic blood pressure, waist-hip circumference, bone or lean mass, or muscle endurance. In conclusion, JRT, when compared to active and passive controls, provides a range of small-moderate benefits that span health- and sport-related physical fitness outcomes.

Season-Long Changes in the Body Composition Profiles of Competitive Female Rugby Union Players Assessed via Dual Energy X-Ray Absorptiometry

Background: Reference data for the body composition values of female athletes are limited to very few sports, with female Rugby Union players having mostly been omitted from such analyses.Methods: Using dual energy X-ray absorptiometry (DXA) scans, this study assessed the body composition profiles (body mass, bone mineral content; BMC, fat mass; FM, lean mass; LM, bone mineral density; BMD) of 15 competitive female Rugby Union players before and after the 2018/19 competitive season. Total competitive match-play minutes were also recorded for each player.Results: Body mass (73.7 ± 9.6 kg vs 74.9 ± 10.2 kg, p ≤ 0.05, d = 0.13) and BMC (3.2 ± 0.4 kg vs 3.3 ± 0.4 kg, p ≤ 0.05, d = 0.15) increased pre- to post-season for all players. Conversely, FM (21.0 ± 8.8 kg), LM (50.7 ± 3.9 kg), and BMD (1.31 ± 0.06 g·cm^-2) were similar between time-points (all p > .05). Accounting for position, body mass (r_partial(12) = 0.196), FM (r_partial(12) = -0.013), LM (r_partial(12) = 0.351), BMD (r_partial(12) = 0.168) and BMC (r_partial(12) = -0.204) showed no correlation (all p > .05) against match-play minutes.Conclusion: The demands of the competitive season influenced specific body composition indices (i.e., body mass, BMC) in female Rugby Union players; a finding which was unrelated to the number of minutes played in matches. While the causes of such differences remain unclear, practitioners should be cognizant of the body composition changes occurring throughout a female Rugby Union competitive season and, where necessary, consider modifying variables associated with adaptation and recovery accordingly.

Relationship Among Motor Behavior, Motor Development, and Motor Performance in Children Aged 7-8 Years in China

For children aged 7-8 years in China, "immobility" is a key problem hindering their physical and mental development in recent years. It is widely accepted that motor performance development in children is accompanied by physical and mental growth and development. However, few studies have clarified the relationship among motor behavior, motor development and motor performance. To bridge this knowledge gap, an empirical analysis of children aged 7-8 years in China was conducted. This study developed scales for testing motor performance, motor behavior and motor performance, respectively, and collected data of these tests on children aged 7-8 years in China. Canonical correlation analysis was used to analyze the correlations among motor performance, motor behavior and motor performance, and partial least squares regression was used to evaluate the relationship between dependent and independent variables. It was found that, for the children aged 7-8 years in China, there were significant positive correlations among the motor performance, motor behavior, and motor development. The three tests were closely related and could be applied to promote children's sports performance through improved training activities for targeting specific indicators. The study found there was no significant differences in the application of the three tests for children with different age and gender. This finding lays a foundation for further testing in older children and meets the measurement requirements of modern medicine's "bio-psycho-social model of health promotion". Additionally, the theoretical motional quotient model of "The Bio-Behavior-Task" is constructed as a comprehensive motor performance evaluation system, aligning with students' physical and mental development standards.

The Influence of Different Rope Jumping Methods on Adolescents' Lower Limb Biomechanics during the Ground-Contact Phase

As a simple and beneficial way of exercise, rope skipping is favored by the majority of teenagers, but incorrect rope skipping may lead to the risk of injury. In this study, 16 male adolescent subjects were tested for bounced jump skipping and alternating jump rope skipping. The kinematic data of the hip, knee, ankle and metatarsophalangeal joint of lower extremities and the kinetics data of lower extremity touching the ground during rope skipping were collected, respectively. Moreover, the electromyography (EMG) data of multiple muscles of the lower extremity were collected by Delsys wireless surface EMG tester. Results revealed that bounced jump (BJ) depicted a significantly smaller vertical ground reaction force (VGRF) than alternate jump (AJ) during the 11−82% of the ground-contact stage (p < 0.001), and the peak ground reaction force and average loading rate were significantly smaller than AJ. From the kinematic perspective, in the sagittal plane, when using BJ, the flexion angle of the hip joint was comparably larger at 12−76% of the ground-contact stage (p < 0.01) and the flexion angle of the knee joint was significantly larger at 13−72% of the ground-contact stage (p < 0.001). When using two rope skipping methods, the minimum dorsal extension angle of the metatarsophalangeal joint was more than 25°, and the maximum was even higher than 50°. In the frontal plane, when using AJ, the valgus angle of the knee joint was significantly larger during the whole ground-contact stage (p < 0.001), and the adduction angle of the metatarsophalangeal joint (MPJ) was significantly larger at 0−97% of the ground-contact stage (p = 0.001). EMG data showed that the standardized value of root mean square amplitude of the tibialis anterior and gastrocnemius lateral head of BJ was significantly higher than AJ. At the same time, that of semitendinosus and iliopsoas muscle was significantly lower. According to the above results, compared with AJ, teenagers receive less GRF and have a better landing buffer strategy to reduce load, and have less risk of injury during BJ. In addition, in BJ rope skipping, the lower limbs are more inclined to the calf muscle group force, while AJ is more inclined to the thigh muscle group force. We also found that in using two ways of rope skipping, the extreme metatarsophalangeal joint back extension angle could be a potential risk of injury for rope skipping.

Speed Rope Skipping - Performance and Coordination in a Four-Limb Task

This study investigated biomechanical characteristics of Speed Rope Skipping (RS) and estimated the contribution of the lower and upper limbs to overall performance. Lower (jumping), upper (turning), and whole-body (skipping) performance were examined in 23 rope skippers. All tests were recorded by 2 D video and nine skipping tests were performed in a 3 D motion capture system. Similar movement patterns were observed for the lower limbs in all participants, while handle trajectories differed in shape and symmetry according to performance. In general, turning unlike jumping performance was close to and significantly correlated with skipping performance. Therefore, it appears that lower extremity movement may be adapted to the limiting capacity of the upper extremity to maintain movement stability.

Impact of Long-Rope Jumping on Monoamine and Attention in Young Adults

Previous research has shown that rope jumping improves physical health; however, little is known about its impact on brain-derived monoamine neurotransmitters associated with cognitive regulation. To address these gaps in the literature, the present study compared outcomes between 15 healthy participants (mean age, 23.1 years) after a long-rope jumping exercise and a control condition. Long-rope jumping also requires co-operation between people, attention, spatial cognition, and rhythm sensation. Psychological questionnaires were administered to both conditions, and Stroop task performance and monoamine metabolite levels in the saliva and urine were evaluated. Participants performing the exercise exhibited lower anxiety levels than those in the control condition. Saliva analyses showed higher 3-methoxy-4-hydroxyphenylglycol (a norepinephrine metabolite) levels, and urine analyses revealed higher 3-methoxy-4-hydroxyphenylglycol and 5-hydroxyindoleacetic acid (a serotonin metabolite) levels in the exercise condition than in the control. Importantly, urinary 5-hydroxyindoleacetic acid level correlated with salivary and urinary 3-methoxy-4-hydroxyphenylglycol levels in the exercise condition. Furthermore, cognitive results revealed higher Stroop performance in the exercise condition than in the control condition; this performance correlated with salivary 3-methoxy-4-hydroxyphenylglycol levels. These results indicate an association between increased 3-methoxy-4-hydroxyphenylglycol and attention in long-rope jumping. We suggest that long-rope jumping predicts central norepinephrinergic activation and related attention maintenance.

Jumping rope and whole-body vibration program effects on bone values in Olympic artistic swimmers

INTRODUCTION

Artistic swimming seems not to benefit bone development like other out-of-water physical activities. To increase bone acquisition, artistic swimming should combine water training with weight-bearing impact or strength activities. Artistic swimmers can be a population at risk of developing osteopenia and osteoporosis in later life. The aim of the present study was to evaluate the effects of a training program on bone mineral density (BMD), bone mineral content (BMC) and body composition in an Olympic artistic swimming team.

METHODS

Sixteen women aged 17-21 years, who train 30 h/week, at the Olympic Training Centre (Barcelona, Spain), were followed up over two seasons. The 1st season involved regular artistic swimming training without specific training to reduce the risk of osteopenia. The exercise intervention, jumping rope and whole-body vibration, was added in the 2nd season. The protocol included 20 min of training 2 days per week, over a 22-week period. Dual energy x-ray absorptiometry measured the bone variables and body composition. The daily diet, medical history and bone turnover markers were evaluated.

RESULTS

The intervention program increased BMD on lumbar spine (2.10%, p = 0.002), total hip (2.07%, p = 0.001), and femoral neck (2.39%, p = 0.02). Lower limb's fat mass decreased (10.17%, p = 0.038). No significant differences were found for any of the measured anthropometric characteristics between both time points in the 1st season. In conclusions, combined jump rope and vibration should be considered to reduce the risk of bone damage in artistic swimmers.

Osteoporosis preventive behaviors in adolescent girls: the educational program based on BASNEF model

Osteoporosis is a progressive and preventable metabolic disease. This study aimed to assess the short-term effect of the educational program based on the Beliefs, Attitude, Subjective Norms, Enabling Factors (BASNEF) model on the osteoporosis preventive behaviors in adolescent girls. It was found that the BASNEF model improved the osteoporosis preventive behaviors in adolescent girls.

PURPOSE

Osteoporosis is a progressive and preventable metabolic disease. This study aimed to investigate the short-term effect of the education program based on the BASNEF model on the osteoporosis preventive behaviors in adolescent girls.

METHODS

This randomized clinical trial was conducted on adolescent girls from January to August 2018 in an urban area of Iran. Subjects were 120 adolescent girls aged 13-14 years studying in the girls' high school that were randomly assigned to intervention and control groups. The data collection tool was the demographic questionnaire and the researcher-made questionnaire consisting of six domains based on the BASNEF model. Validity and reliability of the questionnaires were confirmed before data collections. The educational program was developed based on the BASNEF model in four sessions lasting from 30 to 45 min. Data was collected before, immediately and 1 month after the educational program and was analyzed via the SPSS software v.18.

RESULTS

No statistically significant differences were reported between the groups in terms of knowledge (p = 0.48), attitude (p = 0.94), subjective norms (p = 0.17), behavioral intention (p = 0.82), enabling factors (p = 0.62), and osteoporosis preventive behaviors (p = 0.32). Meanwhile, immediately and 1 month after the educational program, differences were reported between the two groups in knowledge (p < 0.001), attitude (p = 0.002, p < 0.001), subjective norms (p = 0.024, p = 0.001), behavioral intention (p < 0.001, p = 0.001), enabling factors (p < 0.001), and osteoporosis preventive behaviors (p < 0.001).

CONCLUSION

It is suggested that educational program based on the BASNEF model is used to strengthen the osteoporosis preventive behaviors among adolescent girls.