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Shah McLean posted an update 6 months, 1 week ago
05) regardless of weight status; screen-based sedentary behavior and waist circumference in girls significantly predicted muscular fitness (β = -0.13 and β = -0.42, p < 0.05).
To increase overall HRF in peripubertal girls and boys, it is important to help them maintain healthy weight status and to promote MVPA and limit screen-based sedentary behavior, especially in adolescent girls.
To increase overall HRF in peripubertal girls and boys, it is important to help them maintain healthy weight status and to promote MVPA and limit screen-based sedentary behavior, especially in adolescent girls.
This study investigated the Whole-body vibration training with the same amplitude and different vibration frequencies was used to compare the difference in bone mineral density (BMD) of the proximal femurs in elderly women.
This study included three age-, height-, and weight-matched groups; the medium-frequency group (n=19) received 24 weeks of whole-body vibration training with a vibration frequency of 20 Hz; the high-frequency group (n=18) received 24 weeks of whole-body vibration training with a vibration frequency of 40 Hz; and the control group (n=19) received no intervention. Changes in the BMD of the proximal femur on the dominant side in the three groups were measured using dual-energy X-ray absorptiometry.
According to the between-group comparison, the BMD of the greater trochanter and Ward’s triangle in the middle-frequency group increased by 7.6% and 13.3%, respectively (P<0.05), while the BMD of the greater trochanter and Ward’s triangle in the high-frequency group increased by 10.6% and 16.9%, respectively (P<0.05). There was no significant difference in BMD between the medium-frequency group and the high-frequency group at 24 weeks (P>0.05).
Whole-body vibration training with a frequency of 20 Hz and 40 Hz improved the BMD of the proximal femurs in elderly women to varying degrees, but had no significant effect on femoral neck BMD. Under the same amplitude conditions, an increase in vibration frequency did not cause further changes in BMD.
Whole-body vibration training with a frequency of 20 Hz and 40 Hz improved the BMD of the proximal femurs in elderly women to varying degrees, but had no significant effect on femoral neck BMD. Under the same amplitude conditions, an increase in vibration frequency did not cause further changes in BMD.
The growth and development cycle of the adult is characterized by substantial changes in physical size and maturity, and is controlled by the simultaneous influence of genetic components and the environment. Changes in the development of bones, muscles and adipose tissue are among the most important aspects of adolescent physical development.
The aim of this research was to examine the correlation between bone mineral density (BMD) and neuromuscular performance in children at different stages of maturation.
The study included 31 participants of both sexes (11.7±1.89 years). Body composition was assessed through bone densitometry using an energy duo X-ray source. The neuromuscular performance of the upper limbs was analyzed by the medicineball hand grip and throwing tests. The lower limbs by the vertical counter motion jump test, and skeletal maturation was analyzed by bone age. selleck chemical Maturation was used as an effect control between the association of BMD and neuromuscular performance.
The results demonstrated significant associations between the performance of upper (p<0.0001) and lower (p=0.01) limbs and BMD. On inter-group comparison for only the accelerated maturational stage, male participants had greater BMD than female participants (p=0.001; effect size = 3.13). Regarding the maturational stages, male participants in the accelerated maturational stage demonstrated higher BMD than those in the normal and delayed maturational stages (p=0.04; effect size = 3.10), whereas female participants did not demonstrate significant differences in BMD accumulation.
BMD has a strong correlation with the neuromuscular performance of upper and lower limbs of children of both sexes.
BMD has a strong correlation with the neuromuscular performance of upper and lower limbs of children of both sexes.
Volleyball players have a high risk of injury in the lower limbs as a consequence of the specific characteristics of the sport, such as repetitive jumps and falls. The objective of the present study was to evaluate the effects of a multidisciplinary injury prevention program on lower limb stability in young volleyball players.
The experimental design was a non-randomized controlled trial. All the measurements were performed in a standardized room in a sports center. Twenty-six young male volleyball players (mean age 15.39±1.16 years-old), divided into experimental (n=15) and control groups (n=11) participated in this study. The experimental group performed an 8-week prevention program including lower limb strength and plyometric training, and joint and core stability. The Y-Balance and force platform landing tests were carried out as the pre- and post-tests.
The main outcome measures were the injuries history, distance and difference reached in anterior, post-lateral and post-medial axis of the Y-Balance test, and the force produced in Z, X and Y axis after landing. Differences were found between groups and measurements in all the variables of the Y-Balance test, except in the frontal axis for the dominant leg and for the differences between legs (p=0.039-0.001); and in the ground reaction forces (Z axis) (p=0.040), the X axis (p=0.014) and the dynamic postural stability index (p=0.025) of the lateral jump with the non-dominant leg.
An 8-week prevention program seems to improve the lower limb stability in young volleyball players.
An 8-week prevention program seems to improve the lower limb stability in young volleyball players.
The purpose of this study was to compare the match demands of officiating 15-a-side rugby union at different competitive levels.
Data was collected using Global Navigation Satellite Systems from 21 referees during 82 competitive rugby union matches across three different competitive levels (1) professional, (2) semi-professional, and (3) amateur.
Compared with referees at the professional and semi-professional levels, referees at the amateur level covered less total distance (p = 0.005). Additionally, these referees covered less distance jogging, and at low and medium intensity (all p < 0.05), and had less time between repeated high-intensity efforts (p < 0.001). Furthermore, compared with referees at the semi-professional and amateur levels, referees at the professional level had a higher sprint duration and covered more distance sprinting (all p < 0.05), and achieved a higher maximal speed during the longest repeated high-intensity effort or “worst-case scenario” (p = 0.026). The professional level referees also displayed a lower average heart rate (p < 0.