Asian Journal of Sports Medicine
Volume:13 Issue: 2, Jun 2022

D-Aspartic acid (DAA) is an amino acid found in the brain and reproductive system. Some investigations have reported beneficial effects of DAA on brain function and reproductive system health by increasing testosterone through the hypothalamic-pituitary-gonadal axis. However, its effect on body composition is unknown. Given testosterone's role in muscle growth, this study aimed to evaluate the effect of DAA supplementation on the body composition of trained males.

PubMed, Scopus, Embase, and Web of Science (until 1 August 2021) were searched for this systematic review. Inclusion criteria assumed as clinical trials assessed the effect of DAA on body composition in trained males. After including articles by keywords, the articles were reviewed for meeting the eligibility criteria. Three independent researchers conducted the search and full-text review.

Among 134 articles located during the primary search, five articles (47 interventions and 43 controls) were included in the study based on eligibility criteria. All included clinical trials had a low risk of bias. A review of the relevant literature concludes that different doses of DAA (three grams, six grams, 7.12, and 12 grams) in different intervention periods (two weeks, four weeks, and 12 weeks) have no effects on body composition in trained males.

DAA supplementation is a low-level booster of testosterone and has no significant effect on the testosterone level in professional male athletes, and cannot alter the body composition.

Menstrual cycle and menstrual symptoms can affect the physical, mental and exercise performance of female athletes.

This study aimed to determine the associated symptoms of premenstrual, menstrual, and postmenstrual periods in female judo athletes by weight class.

The participants were 169 female judo athletes aged between 18 and 21 years (age 19.5 ± 1.1 years, height 1.6 ± 0.1 m, body mass 64.8 ± 12.1 kg). Weight class and physical characteristics were measured using a questionnaire. Associated menstrual symptoms were measured using the Menstrual Distress Questionnaire (MDQ). For the purposes of this study, athletes of < 48 kg, < 52 kg, and < 57 kg weight were defined as “lightweight,” athletes of < 63 kg and < 70 kg as “medium weight,” and athletes of < 78 kg and > 78 kg as “heavyweight.”

In the postmenstrual MDQ score, the scores for “lack of autonomic nervous system coordination” (P = 0.037), “poor concentration” (P = 0.046) and “water conservation” (P = 0.030) were higher in the lightweight ranks than in the medium and heavyweight ranks (P < 0.05). Scores for negative postmenstrual effects tended to be higher in the lightweight ranks than in the medium and heavy weight ranks (P = 0.053). For other items, there were no significant differences between the medium and heavy weight ranks and the lightweight ranks before, during, or after menstruation.

This study shows that the degree of postmenstrual symptoms in female judo athletes varies with weight class. These results will contribute to support the condition of female judo athletes based on their menstrual cycle by weight class.

All sporting events were halted due to the COVID-19 pandemic, and many athletes suffered from the infection.

This study aimed to evaluate the clinical characteristics and training days lost to COVID-19 in professional football.

This questionnaire-based report on COVID-19 symptoms was conducted during the 2019-20 Iranian men's premier league and second division football. Team members with positive PCR tests were enrolled in the study and were told to fill in the questionnaire after the resolution of the symptoms. The questionnaire was designed to measure the frequency, severity, and duration of COVID-19-related symptoms.

Out of 133 males, including 86 players and 47 team officials with a mean age of 30.81 ± 10.7 years, 63.2% reported experiencing no symptoms. The most frequent symptom was the loss of smell, while the least frequently reported symptom was gastrointestinal unrest. It was also revealed that our population missed an average of 12.89 days to return to the team training.

Since most of the infected individuals in our population were asymptomatic proper case identification using regular PCR testing could stop the transmission of the disease more effectively. Also, more attention is required to be paid to less severe symptoms such as the loss of smell and taste. Moreover, the days lost due to COVID-19 are almost comparable to the days lost by other injuries for the players, which highlights the importance of taking proper preventive measures.

The current study investigates the relationship between simple reaction time, choice reaction time, and eye-hand coordination with peripheral vision in elite female table tennis players. Ten female table tennis players of the Iranian national team with a mean age of 19.7 ± 5.964, in the 18th Asian Games of 2018, Jakarta, participated via convenience sampling. The visual field was evaluated with the Humphrey automated perimetry. Choice and simple reaction time were assessed using Deary-Liewald reaction time tester software. In order to measure eye-hand coordination, the manual test of alternate-hand wall toss was used. Data were analyzed in statistical package for the social sciences using Pearson’s correlation. The results show that there was no significant relationship between simple and choice reaction time with peripheral vision in the left and right eyes. Also, results show that there was no significant relationship between eye-hand coordination with peripheral vision in the left and right eyes (P ≤ 0.05). The findings of this study show that experts in an activity visually searched their environment and located essential information more effectively and efficiently than novices. Therefore, we know that this visual feature is more a function of expertise than visual acuity.

The role of exercise in osteoporosis prevention has been proven. Nevertheless, there is no consensus about the types of sports, especially at professional levels. Non-impact sports such as swimming may have a negative effect or no effect.

Thus, the present study aimed to compare the effect of different sports on bone mineral content (BMC) and bone mineral density (BMD) of elite female athletes.

This was a cross-sectional study consisting of 48 athletes in five groups of long-distance running, volleyball, basketball, swimming (n = 12 for each), and ten control subjects. For measuring the lumbar spine (L2 - L4) and proximal femur (femoral neck, trochanter, and Ward’s triangle), the dual-energy X-ray absorptiometry (DEXA) method was applied.

Indicated that the running, basketball, and volleyball groups had a significantly higher lumbar spine and proximal femur BMD than the swimming and control groups (P < 0.05). Running resulted in significantly higher lumbar spine BMC compared to volleyball, basketball, swimming, and control groups, respectively (P < 0.01), while basketball had higher proximal femur BMC than running and controls (P < 0.01). The Z-score of the lumbar spine in the running was significantly higher than in basketball, swimming, and controls (P < 0.05), while basketball had a significantly higher femur neck Z-score than volleyball, running, and controls (P < 0.001). Finally, the swimmers had significantly higher Z-scores in the lumbar and the proximal femur than non-athletes (P < 0.001).

Although all sports are effective for improving the bone health, the swimmers had much better bone status than non-athletes, while the sports of long-distance running and basketball were more efficient than others; therefore, a combination of endurance and jumping exercises seems to be the best way to prevent osteoporosis.

The sedentary lifestyle caused by the COVID-19 quarantine has resulted in a devastating threat to human health due to stress and anxiety. Although infected individuals must stop exercising, exercise is not prohibited when without symptoms and complications. Whereas exercise can be effective in immune system reinforcement during the prevention, recovery, and post-recovery stages, COVID-19-recovered Individuals (CRI) must exercise under accurate considerations.

This study aimed to study exercise in cold weather for the CRI.

This article overviews how different exercises affect the immune system. PubMed, Science Direct, and Google Scholar Databases and keywords including cold weather, COVID-19, immune system, and combined exercise were used to access scientific articles.

Recent reports show that different sports and exercises significantly improve COVID-19 symptoms, although there are many discrepancies among researchers in prescribing exercise programs (various training protocols, duration, and intensity). Also, CRI should avoid exercise in cold weather due to breathing complications

Based on the present study, regular exercises (aerobic, resistance, and combined) with moderate intensity improve COVID-19 symptoms and the immune system.

Researchers are pursuing the enhancement of sensorimotor skills through the application of virtual reality (VR) in the sports environment.

This study aimed to compare the performance and kinematics of VR with real-world dart-throwing.

Twenty-four healthy junior high school boy students participated (aged = 13.66, SD = 0.48) in this semi-experimental study in the year of 2017. We examined mean radial and bivariate variable errors as the performance variables. The maximum flexion angle, release time angle, and angular velocity was examined as the kinematic variables. Standard dartboard, the Xbox360, the Kinect, and a high-speed camera (sampling at 240 Hz) were used to measure the performance and kinematics characteristics of upper limb motion. We used Kinovea 0.8.26 and MATLAB R2015b to analyze videos and data smoothing. One-way MANOVA was used to analyze variables.

The results revealed (P = 0.392) no significant differences in MRE between VR and real-world (RW) training in pre-test, acquisition, and retention outcomes, F (3, 20) = 1.05. The results indicated (P = 0.024) significant differences in BVE between VR and RW training in the pre-test, F (5.83). In addition, kinematic dependent variables (P = 0.692) had no significant difference between groups, F (9, 14) = 0.711.

These findings achieved the same results in performance and kinematics of dart-throwing by VR intervention in the RW context. Basic similarities between VR and RW movement patterns in the same task bring motor skills improvement and transfer of learning.