Asian Journal of Sports Medicine
Volume:10 Issue: 3, Sep 2019

It is unknown whether the use of cushioned footwear with custom insoles for 10-km runners with shin splints if effective in attenuation of running impact. The aim of this study was to determine the effects of cushioned (footwear with custom insoles) and non-cushioned (barefoot) running on impact in 10-km runners rehabilitated after unilateral shin splint. Twenty patients (mean age 30.5 ± 9.3 years; mean body mass index 23.4 ± 2.0 kg/m2 ) were assessed under two randomly assigned conditions for this cross-sectional study. To measure impact in 10-km runners, the time and frequency domains of impact were obtained through accelerometry, and the reconstructed time-domains, calculated during running, from footwear with custom insoles as compared to control conditions (barefoot) were compared for statistically significant differences. Insoles were customized based on pressure distribution and foot shape. Mean impact was reduced (P < 0.001) from 6.9 g in the control condition to 6.5 g in the cushioned condition. The spectrum frequency was lower (P < 0.001) for the cushioned condition between 5.8 and 40.5 Hz. The reconstructed time-domain impact signal had an r = 0.38 ± 0.21 and R2 = 14.3% in relation to the impact signal. The impact and frequency spectrums were attenuated in the band of 5.8 to 40.5 Hz for cushioned condition. Running footwear with custom insole designs reduce impact during running, establishing an appropriate strategy to diminish tibial stress after shin splint in runners.

Impact and lower extremity joint angles during landing are factors that can increase the risk of anterior cruciate ligament injuries. However, the correlations between these factors and lower extremity muscle activation during the flight phase, which may affect these factors, are unknown. The present study aimed to clarify the correlations between the peak vertical ground reaction force (pVGRF), sagittal joint angles during the landing phase, and the vastus medialis (VM) and semitendinosus (ST) muscle co-contraction index (CCI) during the flight phase in single-leg jump-landing. Fourteen healthy, physically active volunteers (age, 22.6 ± 2.7 years; height, 164.4 ± 7.6 cm; body weight, 58.9 ± 8.9 kg; body mass index, 21.7 ± 2.3 kg/m2 ) participated. All subjects performed a single-leg jump-landing task. The pVGRF variables and the sagittal joint angles during the landing phase were measured. The CCI between the VM and ST during the flight phase was measured. The correlations between the VGRF variables, sagittal joint angles, and CCI were assessed using Spearman’s rank correlation coefficient. The knee flexion angle at the pVGRF was negatively correlated with the magnitude of pVGRF (ρ = -0.609, P = 0.021). The knee flexion angle at the pVGRF was negatively correlated with the CCI during the flight phase in single-leg jump-landing (ρ = -0.627, P = 0.016). An excessive CCI between the VM and ST during the flight phase might be indirectly related to a greater landing impact after a single-leg jump.

It has been established that injury incidence data and training load in table tennis is somewhat limited. The purpose of this study was to analyze and report training load and injury incidence. This was established over a full season in highly trained youth table tennis athletes. We further aimed to establish what variables related to training load have a statistically significant effect on injury in youth table tennis. Data was collected from eight male adolescent table tennis players of Arabic origin. Training and game time were monitored continuously throughout each training session and match. Heart rate was measured throughout and then subsequently analyzed to quantify internal training load. Players were subjected to an average of 1901 h 33 min±44 h 30 min of training time and 140 h 0 min±11 h 29 min of game time over the season. Overall injury incidence was 8.3 (95% CI: 4.6 - 12.0), time-loss injuries 4.4 (95% CI: 1.9 - 6.9) and growth conditions 2.0 (95% CI: 0.6 - 3.3) per 1000 hours. Internal training loads quantified via the Edwards training impulse equation were significantly different between training weeks (P = 0.001), with lowest values around competition periods (P < 0.05). For every extra auxiliary unit of relative training load per minute during training, a significant increase (P = 0.014) in injury occurrence was present. Most of the injuries occurred during the first quarter of the year (65%), when training loads were highest. In conclusion, the results of this preliminary study showed that training loads increase during a season until competition period, with relative training load per minute being linked to the likelihood of injuries. The rate of overuse injuries and growth-related conditions were higher than previously reported in adolescents in other racket sports.

As part of type 2 diabetes mellitus (T2DM) lifestyle management, exercise programs must be demonstrably effective and safe. A randomized controlled trial (RCT) was used to evaluate the results of glycemic control and oxidative stress of a new T2DM management exercise program in a training facility setting. The study participants were randomly allocated into either an experimental (EXP) group who participated in the new training program or a control (CTR) group who participated in continuous cardiorespiratory exercise. Each participant’s glycemic control (glycated hemoglobin A, HbA1c), fitness level (maximum oxygen uptake, VO2max), and oxidative stress (malondialdehyde, MDA and superoxide dismutase, SOD) were measured before and after the training program. The 12-week training program combined high-intensity interval training (HIIT) three times a week with resistance training (RT) twice a week while gradually increasing the intensity. The HIIT element was comprised of one minute of high-intensity exercise and four minutes of low-intensity exercise. The RT element was comprised of nine exercises for the core, upper extremities, and lower extremities. The 42 T2DM patients who participated in this RCT were 35 - 64 years old. The HbA1c level of the EXP group decreased (∆ = -0.43 ± 1.01%), although not significantly. The VO2max was higher in the EXP group (38.13 ± 5.93 mL/kg/min) than in the CTR group (32.09 ± 5.24 mL/kg/min, P = 0.004). The overall oxidative stress decreased in the EXP group (MDA level ∆ = -0.14 ± 0.39 nm/mL) when compared to the CTR group (MDA level ∆ = 0.18 ± 0.26 nm/mL, P = 0.011), and the SOD level significantly increased more in the EXP group [median ∆ = 0.47 U/mL (interquartile range = 0.08 - 0.74 U/mL)] when compared to the CTR group (∆ = 0.14 ± 0.35 U/mL, P = 0.036). The EXP group’s composite effects score was significantly higher (8.72 ± 1.27) than the CTR group’s score (7.20 ± 1.08, P = 0.001). The combined HIIT and RT exercise program was not significantly improving glycemic control, however it lowered oxidative stress.

Alzheimer’s disease is one of the most common causes of dementia with metabolic disorders in the nervous system. Nutrition and physical activity are two main factors in the management of this disease. The aim of the present study was to investigate the effect of endurance training with crocin consumption on IGF-1 and glycogen expression in rat hippocampus tissue of a trimethyltin-treated model of Alzheimer’s disease.

In this experimental study, 30 male rats were selected and divided into 5 groups of 6 rats including (1) healthy control, (2) Alzheimer’s control, (3) endurance training, (4) crocin and (5) endurance training with crocin. At first, rats in groups 2 - 5 were induced Alzheimer’s disease by intraperitoneal injection of 8 mg/kg of trimethyltin. Then, during 8 weeks, rats in groups 3, 5, ran on treadmill for 3 sessions per week, each session 15 - 30 minutes at speeds of 15 - 20 m/min and groups 4 and 5 received 25 mg/kg of crocin daily. The results were analyzed by Shapiro-Wilk test and one-way ANOVA with Tukey post hoc (P ≤ 0.05).

Alzheimer’s induction with trimethyltin had a significant effect on reduction of IGF-1 gene expression (P = 0.001) and glycogen (P = 0.001); endurance training had a significant effect on increase of IGF-1 (P = 0.001) and glycogen (P = 0.001); crocin consumption had no significant effect on IGF-1 (P = 0.48) and glycogen (P = 0.39); endurance training with crocin consumption had significant effect on increase of IGF-1 (P = 0.001) and glycogen (P = 0.02) as well as endurance training (P = 0.001) and endurance training with crocin consumption rather than crocin consumption had significant effect on increase of IGF-1.

Although endurance training results in a significant increase in IGF-1 and glycogen in the hippocampus tissue of Alzheimer’s rats, nonetheless, the use of crocin in combination with endurance training rather than crocin consumption alone can have a greater effect on increased IGF-1 content of the hippocampus in rats with Alzheimer’s.

The length and number of accessory bands of gracilis and semitendinosus tendons have high variability among Asian population. Complications during graft harvesting might occur if the surgeon cannot correctly identify these complex structures.

We performed cadaveric knee specimen dissections (level of evidence: level III; descriptive laboratory study (anatomical study)). Each of the accessory bands arising from semitendinosus and gracilis tendons was identified. Size and distance from the origin of accessory bands to the tibial insertion were measured.

Eighty knees were included in the study. For the semitendinosus tendon, we found the following accessory bands in our specimens: no accessory bands in 6%, one band in 56%, and two bands in 38%. The longest distance of an accessory band from tibial insertion was 9.8 cm, with an average distance for the first band of 4.5 cm. The number of accessory bands for the gracilis tendon was, as follows: 0, 1, 2, 3 and 4 in 20, 39, 31, 9, and 1%, respectively. The longest distance of accessory band was 9.33 cm from tibial insertion, with an average distance for the first band of 4.7 cm. We found the width of accessory bands in females to be wider than males (P = 0.0001) and the width of accessory bands in right knees to be wider than those in left knees (P = 0.04).

In Asian populations, we found high variability of number of accessory bands from semitendinosus and gracilis tendons. The average distance from the tibial insertion to the first accessory band was 4.5 cm. None of the bands arised more than 10 cm from the tibial insertion.

Meniscal tear surgeries have many long term sequelae. Intra-articular platelet rich plasma injection is thought to stimulate repair and increase meniscal function.

To assess the effect of 6-monthly intra-articular injection of platelet rich plasma (PRP) on the pain assessment and functional status of knee joint undergone meniscal repair.

A randomized controlled trial was carried out on thirty patients who had undergone arthroscopic meniscal repair and presented with persistent pain within 4 months after surgery. Half of the patients were randomly intra-articularly injected with 5 mL PRP at 1 month intervals for 6 injections and the other half were not injected and taken as a control group. Clinical examination, visual analogue scale (VAS), knee injury and osteoarthritis outcome score (KOOS) score and Doppler ultrasonography were performed before and after PRP treatment.

After 6 months, in the PRP injected group, there was a significant improvement in VAS score (1 (1 - 3)) and KOOS score (86.2 ± 4) compared to baseline values (9 (7 - 10) and 62 ± 9.8 respectively; P < 0.001) as well as significant decrease in the percentage of degeneration of medial femoral condyle (MFC), lateral femoral condyle (LFC), medial tibial condyle (MTC), lateral tibial condyle (LTC) measured by Doppler Ultrasonography (US), (6.16 ± 3.33 and 9.07 ± 3.66, respectively; P = 0.031).

This study showed that intra-articular PRP injection following meniscal repair can be effective in reducing pain, improving knee function, and slowing the rate of cartilage degeneration that accounts for early osteoarthritis.

Warm-up including dynamic stretching is a popular and widely accepted practice as a pre-exercise routine for athletes. However, a shortage of studies investigating the impact of dynamic stretching on linear repeated-sprint performance exists.

The present study aims to look at the effect of different volumes of dynamic stretching on 30 m linear repeated sprint performance in team sport athletes.

Fifteen male university team-sport players [age (mean ± SD) 22.1 ± 0.6 years, stature 166.9 ± 6.6cm and body mass 67.5 ± 8.0kg] underwent 3 sessions in this within-subjects counterbalanced study. All sessions included a general warm-up (5-minutes self-paced), followed by a dynamic stretching protocol (one set-DSS1; two sets-DSS2; three sets-DSS3) comprised of five active dynamic exercises for lower body musculature (gastrocnemius, gluteals, hamstrings, quadriceps and hip extensor). A standardized specific warm-up was then undertaken followed by a repeated-sprint test (6 × 30-m sprint with 30 seconds active recovery).

Values for average sprint time (AST) and total sprint times (TST) were significantly faster (P = 0.005) following DSS2 compared to DSS1 and DSS3. Fatigue index (FI) was significantly lower in DSS2 compared to DSS1 and DSS3 (P < 0.0005). Heart rate responses and blood lactate also showed significantly lower (P < 0.05) values during the repeated sprint test in DSS2. No differences were established (P > 0.05) for best sprint time (BST), mean sprint time (MST) or rating of perceived exertion (RPE).

In conclusion, a dynamic warm-up consisting of two sets resulted in improved performance in repeated-sprint. The exact mechanisms associated with this established ergogenic benefit is still unclear and requires more research.