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Postactivation potentiation is referred to as an acute and temporary enhancement of muscle performance resulting from previous muscle contraction. The purpose of this study was to compare the acute effect of plyometric exercise (PLY) and heavy-resistance exercise (RES) on the blood lactate level (BLa) and physical performance. Fourteen male collegiate soccer players were randomized to perform either RES or PLY first and then crossed over to perform the opposite intervention. PLY consisted of 40 jumps, whereas RES comprised ten single repetitions at 90% of one repetition maximum. BLa and physical performance (countermovement jump height and 20-m sprint) were measured before and at 1 and 10 min following the exercise. No significant difference was observed in the BLa for both exercises (PLY and RES). Relative to baseline, countermovement jump (CMJ) height was significantly better for the PLY group after 1 min (P = 0.004) and after 10 min (P = 0.001) compared to that of the RES group. The 20-m sprint time was significantly better for PLY at 10 min (P = 0.003) compared to that of RES. The present study concluded that, compared to RES, PLY causes greater potentiation, which leads to improved physical performance. This trial is registered with NCT03150277.

[Purpose] The present study aimed to determine the changes in physical and balance performance following exercise-induced muscle damage using a sport-specific protocol. [Subjects and Methods] Fifteen collegiate soccer players were asked to perform a sport-specific sprint protocol to induce muscle damage. The markers of muscle damage (soreness, range of motion, limb girth, muscle strength, creatine kinase and lactate dehydrogenase), physical performance (speed, agility and power) and balance (static and dynamic balance) were assessed at baseline and 24, 48 and 72 hours following the sprint protocol. [Results] All variables, including the markers of muscle damage, physical performance and balance showed a significant difference when assessed at the 4 time points. [Conclusion] The study demonstrated that both the physical and balance performance were affected following repeated sprint protocol in soccer players. It is recommended the balance performance of an athlete be continually assessed following exercise-induced muscle damage so as to determine the appropriate return to sport decision thereby, minimizing the risk of further injury.

Objective: The purpose of this study was to compare the effects of neuromuscular training (NMT) and quadriceps training (QT) on the altered gait patterns and Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index in patients with knee osteoarthritis (OA) and varus malalignment. Methods: Sixty-six patients with knee pain ≥2 on 100-mm visual analog scale, radiographic knee OA changes ≥2 on Kellgren-Lawrence grading scale, and genu varum were allocated randomly into either the neuromuscular training group or quadriceps training group. Twelve weeks of supervised exercise protocol was given to the participants of both groups, which included 3 sessions per week. Primary outcomes were gait variables and self-reported physical function (WOMAC index). Results: Of 66 knee OA patients, only 31 (94%) in the NMT group and 28 (84.8%) in the QT group completed the exercise protocol and were included in the analysis. There was a significant improvement in gait velocity (P = .022), stride length (P = .009), and global WOMAC index (P = .011) in the NMT group compared to the QT group. However, the scores of cadence (P = .226), gait cycle (P = .332), and double limb support (P = .054) were not found significant in the NMT group compared with the QT group. Conclusion: The NMT group showed improvement in some of the gait parameters as well as improvement in pain, stiffness, and functional limitation compared with conventional QT. No additional improvement was found in cadence, gait cycle, and double limb support in patients who received NMT.

Magnetite (Fe 3 O 4 ) nanoparticles (NPs) and SiO 2 -coated Fe 3 O 4 nanoparticles have successfully been synthesized using co-precipitation and modified Stöber methods, respectively. The samples were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, high-resolution transmission electron microscopy (HRTEM), vibrating sample magnetometer (VSM) techniques, X-ray absorption spectroscopy (XAS), and X-ray magnetic circular dichroism (XMCD). XRD and FTIR data confirmed the structural configuration of a single-phase Fe 3 O 4 and the successful formation of SiO 2 -coated Fe 3 O 4 NPs. XRD also confirmed that we have succeeded to synthesize nano-meter size of Fe 3 O 4 NPs. HRTEM images showed the increasing thickness of SiO 2 -coated Fe 3 O 4 with the addition of the Tetraethyl Orthosilicate (TEOS). Room temperature VSM analysis showed the magnetic behaviour of Fe 3 O 4 and its variations that occurred after SiO 2 coating. The magnetic behaviour is further authenticated by XAS spectra analysis which cleared about the existence of SiO 2 shells that have transformed the crystal as well as the local structures of the magnetite NPs. We have performed XMCD measurements, which is a powerful element-specific technique to find out the origin of magnetization in SiO 2 -coated Fe 3 O 4 NPs, that verified a decrease in magnetization with increasing thickness of the SiO 2 coating. Graphical Abstract Magnetite (Fe 3 O 4 ) nanoparticles (NPs) and SiO 2 -coated Fe 3 O 4 nanoparticles have successfully been synthesized using co-precipitation and modified Stöber methods, respectively. The samples were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, high-resolution transmission electron microscopy (HRTEM), vibrating sample magnetometer (VSM) techniques, X-ray absorption spectroscopy (XAS), and X-ray magnetic circular dichroism (XMCD). XRD and FTIR data confirmed the structural configuration of a single-phase Fe 3 O 4 and the successful formation of SiO 2 -coated Fe 3 O 4 NPs. XRD also confirmed that we have succeeded to sy...