The aim of this study was to investigate the effect of leg blood flow restriction (BFR) applied during a 3-a-side futsal game on strength-related parameters. Twelve male futsal players were randomly assigned into two groups (n = 6 for each group) during 10 training sessions either with or without leg BFR. Prior to and post-training sessions, participants completed a series of tests to assess anabolic hormones and leg strength. Pneumatic cuffs were initially inflated to 110% of leg systolic blood pressure and further increased by 10% after every two completed sessions. In comparison with baseline, the resting post-training levels of myostatin (p = 0.002) and IGF-1/MSTN ratio (p = 0.006) in the BFR group changed, whereas no change in the acute level of IGF-1 and myostatin after exercise was observed. Peak torque of knee extension and flexion increased in both groups (p < 0.05). A trend of increased neural activation of all heads of the quadriceps was observed in both groups, however, it was statistically significant only for rectus femoris in BFR (p = 0.02). These findings indicated that the addition of BFR to normal futsal training might induce greater neuromuscular benefits by increasing muscle activation and augmenting the hormonal response.

Laptop work may increase risks of neck and back injuries in the long term due to awkward postures and increased mechanical loads on cervical and lumbar spine. This study was intended to compare the muscle activities and postural changes as well as discomfort of the neck and back resulted from the laptop work in a conventional and adjusted setup. 20 young healthy males performed two 8-min sessions of computer-mouse work and typing in a conventional setup and in an ergonomically adjusted setup during laptop work. In the adjusted setup, the screen height was individually adjusted by a riser and the keyboard was externally connected. The posture of the cervical, thoracic, lumbar spines, and shoulder, as well as electromyographic activity of cervical and lumbar erector spinae, multifidus, upper trapezius and anterior deltoid muscles, were recorded during the first and last 2 min of each computer work session. Having completed the computer work session, furthermore, the participants scored their neck, back, and general discomfort. The very research findings implied that adjusting the screen height and keyboard placement was effective during laptop work in reducing the cervical (−4.53 deg) and thoracic flexion angles (−3.14 deg) as well as the cervical erector spinae (−10.31%) and multifidus (−15.57%) muscle activities, and resulted in lower discomfort. The typing task was associated with higher muscle activity and awkward posture compared with the mouse work. As for workstation setup, simple modifications may reduce risk factors of musculoskeletal complaints.

Background: The performing of jump and landing in futsal simultaneous with divided attention is one of the most common mechanisms of non-contact anterior cruciate ligament (ACL) injury. Neuromuscular training has effectively reduced the risk of ACL injury, but the effect of neurocognitive training has received less attention. This study investigated the effect of combining 8 weeks of neuromuscular training with dual cognitive tasks on the landing mechanics of futsal players with knee ligament dominance defects. Methods: Thirty male futsal players (mean ± SD: age: 21.86 ± 3.27 years) with knee ligament dominance defects were purposefully identified by the tuck jump test and were randomly divided into the intervention and the control group. The intervention group performed dual task (DT) training for three weekly sessions for 8 weeks and 60 min each, while the control group only did activities of daily living. During the drop vertical jump test, 2D landing kinematics in two moments of initial contact (IC) and full flexion (FF) were assessed. Data were analyzed by means of 2 × 2 repeated measures ANOVA followed by post hoc comparison (Bonferroni) at the significance level of (α ≤ 0.05). Results: A significant improvement was observed in the intervention group compared to the control group for the dynamic knee valgus at IC (F_1,28 = 6.33; P = 0.02, ES = 0.31) and FF (F_1,28 = 13.47; P = 0.003, ES = 0.49), knee flexion at IC (F_1,28 = 20.08; P = 0.001, ES = 0.41) and FF (F_1,28 = 13.67; P = 0.001, ES = 0.32), ankle dorsiflexion at IC (F_1,28 = 37.17; P = 0.001, ES = 0.72) and FF (F_1,28 = 14.52; P = 0.002, ES = 0.50), and trunk flexion at FF (F_1,28 = 20.48; P = 0.001, ES = 0.59) angles. Changes in the trunk flexion at IC (F_1,28 = 0.54; P = 0.47, ES = 0.03) and trunk lateral flexion at IC (F_1,28 = 0.006; P = 0.93, ES = 0.00) and FF (F_1,28 = 2.44; P = 0.141, ES = 0.148) angles were not statistically significant. Conclusions: DT training compared to the control group improved landing mechanics in futsal players with knee ligament dominance defects. Trial registration: Current Controlled Trials using the IRCT website with ID number IRCT20210602051477N1 prospectively registered on 20/06/2021.

The aim of the present study was to predict the kinematics of the knee and the ankle joints during a squat training task of different intensities. Lower limb surface electromyographic (sEMG) signals and the 3-D kinematics of lower extremity joints were recorded from 19 body builders during squat training at four loading conditions. A long-short term memory (LSTM) was used to estimate the kinematics of the knee and the ankle joints. The accuracy, in terms root-mean-square error (RMSE) metric, of the LSTM network for the knee and ankle joints were 6.774 ± 1.197 and 6.961 ± 1.200, respectively. The LSTM network with inputs processed by cross-correlation (CC) method showed 3.8% and 4.7% better performance in the knee and ankle joints, respectively, compared to when the CC method was not used. Our results showed that in the prediction, regardless of the intensity of movement and inter-subject variability, an off-the-shelf LSTM decoder outperforms conventional fully connected neural networks.

Falling is one of the most common causes of hip fracture and death in older adults. A comparison of the biomechanics of the gait in fallers and non-fallers older adults, especially joint coordination and coordination variability, enables the understanding of mechanisms that underpin falling. Therefore, we compared lower-extremity intra-joint coordination and its variability between fallers and non-fallers older adults during gait. A total of 26 older adults, comprising 13 fallers, took part in this study. The participants walked barefoot at a self-selected speed on a 10-m walkway. Gait kinematics in the dominant leg during 10 cycles were captured with 10 motion tracking cameras at a sampling rate of 100 Hz. Spatiotemporal gait parameters, namely, cadence, walking speed, double support time, stride time, width, and length, as well as intra-joint coordination and coordination variability in the sagittal plane were compared between the two groups. Results showed that fallers walked with significant lower cadence, walking speed, and stride length but greater double support and stride time than non-fallers. Significant differences in the ankle-to-knee, knee-to-hip, and ankle-to-hip coordination patterns between fallers and non-fallers and less coordination variability in fallers compared to non-fallers in some instants of the gait cycles were observed. The differences in spatiotemporal gait parameters in fallers compared to non-fallers may indicate an adaptation resulting from decreased efficiency to decrease the risk of falling. Moreover, the differences in segment coordination and its variability may indicate an inconsistency in neuromuscular control. It may also indicate reduced ability to control the motion of the leg in preparation for foot contact with the ground and the knee and ankle motions during loading response. Finally, such differences may show less control in generating power during the push-off phase in fallers.