نشریه مطالعات طب ورزشی
پیاپی 33 (پاییز 1401)

Pronated and supinated foot as common foot deformity with biomechanical changes in walking can cause injury to the lower limbs. In this quasi-experimental study, 10 men with pronated foot, 10 supinated foot and 10 healthy people aged 20-30 years volunteered to participate. A biometrics electromyographic machine was used to record the frequency spectrum of selected muscles. DataLight biometrics software was used to extract the frequency of selected muscles during 3 phases of walking. The results showed that the frequency of Rectus femoris muscle and the Gluteal muscles increased during the loading phase of walking on the grass compared to the ground. Gastrocnemius muscle and Vastus lateralis muscle activity is higher in the healthy group than in the pronated and supinated groups. The results of the present study show that the use of artificial turf for people with foot deformities can be useful due to the increased activity of Rectus femoris muscle and the Gluteal muscles during the loading phase.

People with knee osteoarthritis suffer from profound proprioception impairment and decreased muscle strength. Massage is mentioned as an intervention that can relieve the symptoms of osteoarthritis. Therefore, this study aimed to evaluate the effect of four weeks of Swedish massage on knee joint proprioception, muscle strength of quadriceps, and osteoarthritis symptoms in adult women with knee osteoarthritis. Thirty women were included by targeted and available sampling (age 52.60±7.30 years old, height 1.57±0.05 m, body mass74.40±9.60 kg). The subjects were randomly divided into two equal control and intervention groups (n=15). The intervention group received the Swedish massage for 4 weeks (12 sessions). During this period, the control group did not receive any interventional protocol. Symptoms of osteoarthritis, muscle strength of quadriceps, and knee joint proprioception were analyzed in the pre-and post-test using the WOMAC questionnaire, handheld dynamometer, and joint angle reconstruction, respectively. A mixed repeated measure test was used for comparison between and within groups. The results showed a significant improvement in the desired variables of the intervention group compared to the control group (P<0.05). So that osteoarthritis symptoms were significantly improved (P=0.001), and quadriceps muscle strength (P=0.001) and knee joint proprioception (P=0.001) were significantly increased. Based on the findings of this study, massage can increase the strength of quadriceps muscles and improve the knee joint proprioception in women with knee osteoarthritis by decreasing pain and improving physical function. Therefore, it is recommended to use this intervention in order to improve strength, joint proprioception, and symptoms in women with knee osteoarthritis.

Recently the reactive neuromuscular training (RNT) has received increasing attention due to its function in decreasing the sport injuries. These exercises help athletes to quickly correct their faulty movement patterns. The aim of this study was to investigate the effect of eight weeks of reactive neuromuscular training on landing kinematics in Female Basketball Players. Thirty three players from the three teams of the Tehran Female's Basketball Premier League participated in this study. The teams were randomly divided into three groups: experimental 1 (n=11), experimental 2 (n=11) and control group (n=11). Experimental group 1 performed prevent injury and enhance performance (PEP) exercises for eight weeks and experimental group 2 performed PEP exercises with RNT instead of regular warming up. The control group performed their usual exercises. The kinematics of the trunk and lower extremity joints during landing were evaluated by pre-test and post-test. Three-dimensional lower-extremity kinematics was measured during drop jump with a single leg landing. Data were analyzed by 2-way repeated measures analysis of variance. The results showed that eight weeks of reactive neuromuscular training had a significant effect on hip flexion angle at landing (F(2,27)=3.40, P=0.04, ηp2=0.20). But there was no significant effect on knee valgus, knee flexion, ankle dorsiflexion, and trunk flexion at the moment of landing following RNT training. The presented results indicated that the injury prevention program using reactive neuromuscular exercises could well modify the athletes' movement patterns toward a lower risk of anterior cruciate ligament injury.

Surface stiffness is a factor affecting the injuries since any change in in the amount of this parameter leads to the increased applied forces. This is a quasi-experimental, causal-comparative, and applied study. The statistical population included 14 volleyball players aged between 18 and 20. The muscles’ electrical activity was recorded by an 8-channel electromyograph based on the SENIAM protocol (Surface ElectroMyoGraphy for the Non-Invasive Assessment of Muscles) on four selected muscles of the lower limb. Mean and standard deviation (SD) were employed for data description, Shapiro-Wilk test for the assessment of data distribution normality, analysis of variance with repeated measures for the effect of surface type on the research variables, and Bonferroni post hoc test was used for the assessment of differences. Furthermore, the repeated measurement test’s results revealed no significant difference between groups in terms of the peak muscle activities in Vastus lateralis muscle and Biceps femoris muscle when jumping and landing on tatami, grass, and sand (p≤0.05); however, the surfaces were significantly different in the tibialis anterior muscle and gastrocnemius muscle (p = 0.00). Besides, there was no significant difference between co-contractions in knee and ankle joint (p≤0.05); the difference was that in the knee joint, the highest average co-contraction was seen on the grass and its lowest rate on the sand, while in the ankle joint, the lowest rate was seen on the sand and the highest rate on tatami.

The purpose of this study was to investigate the effect of 12 weeks water training in shallow and deep part of pool on balance and lower limb muscles strength in elderly. Thirty-six healthy male elder selected as statically sample in three groups. Two experimental groups performed 12 weeks water training in shallow and deep part of pool for three sessions in per week. Balance and lower limb muscles strength tests performed before and after the training protocol. Single leg stance time and Y test were used for measuring static and dynamic balance respectively. MMT system was used for measuring lower limb muscles strength. Findings of this study indicated there is significant improvement on static balance after performing training protocol in shallow and deep part of the pool (p=0.03) .in contrast, dynamic balance of dominance leg has significant improvement in 3 directions of Y test while dynamic balance of non-dominance leg has significant improvement in anterior direction only (p=0.01). On the other hand, there is only significant improvement in hamstring muscles strength after training protocol in shallow part of the pool while all muscles strength except internal and external rotators have significant improvement after training protocol in deep part of the pool (p<0.05). It seems 12 weeks water training in shallow and deep part of pool has significant improvement on balance but performing training in deep part of pool has more significant improvement on lower limb muscles strength in elderly.

Due to the lack of study on the transition effect of the lower body to upper body plyometric training, the aim of this study was to investigate the effect of upper and lower body plyometric training on upper-body electromyography activity in young athletes.

36 male students were selected and divided into three groups: - control; - Upper body plyometric; and - Upper-lower body plyometric (mixed) training. Plyometric exercise protocol (4 weeks/ 3 sessions) included push-up plyometric (4 sets/ 10 repetitions) performed by both groups. The mixed group also continued lower-body plyometric exercise (4 sets/ 10 repetitions on obstacles). At the beginning and end of the course, First, anthropometric tests (fat and fat free mass); and functional (Wingate, overhead medicine ball throwing, and deadlift) was performed simultaneously with electromyography data evaluating.

The physiological work doesn't changed significantly in selected muscles (p>0.05). The median of frequency was significantly reduced in the mixed group compared other groups (p<0.05). In addition, there was no difference in anthropometric, overhead medicine ball throwing, absolute and relative mean anaerobic power between groups (p>0.05). In the deadlift, the mixed group had better significantly records than the upper body group (p<0.05). In the relative anaerobic peak power, there was significant differences between training groups with control (p<0.05).

Based on the findings regarding the confirmed role of lower body plyometric training on the transmission of force into the upper body, it is recommended that athletes use lower body plyometric along with upper body plyometric training.