Peak Power Research Articles

Setting sail for Paris 2024: Retrospective analysis of world-class ILCA 7 Olympic sailors' cardiorespiratory fitness (2015-2020).

The aim of this retrospective analysis was to provide a more comprehensive understanding of the cardiorespiratory profile of world-class ILCA-7 sailors (n=3, all males), through a longitudinal evaluation offering real-world data on physiological profile and exercise intensity domains. The cardiopulmonary exercise testing (CPET) was performed by the same researchers using the same equipment during the study. Assessments took place twice a year, aligning with major international competition preparations. Participants trained and competed at the same sailing club in Split, Croatia, under consistent supervision from the same team throughout the study, winning a total of 21 medals at major international competitions. The recorded ranged from 51.7±1.6 to 61.9±3.0mLmin-1kg-1, respectively. Similarly, peak power output varied from 352±10 to 426±34W. The changes in physiological responses at the ventilatory thresholds were proportional to the changes in peak cardiorespiratory fitness capacity. Interestingly, the oxygen pulse measured in 2015 was 25±1mLO2beat-1. Over the subsequent 6 years, the O2 pulse marginally increased and appeared to stabilize at 27±1mLO2beat-1 in 2020, when these athletes were 32±3 years old. This work offers a broader understanding of world-class Olympic sailors' cardiorespiratory fitness, going beyond the standard assessment of peak to incorporate an analysis of ventilatory thresholds. While a direct link between cardiorespiratory fitness and competitive success remains ambiguous, the importance of a well-rounded aerobic capacity for excellence in ILCA-7 sailing class is evident. HIGHLIGHTS: What is the central question of this study? What are the temporal changes in the physiological profiles of three world-class ILCA-7 sailors? What is the main finding and its importance? Data on oxygen pulse adjustments suggest the involvement of compensatory cardiovascular mechanisms, likely associated with the isometric and quasi-isometric contractions inherent in ILCA-7 sailing. This is evidenced by the absence of an age-related increase in oxygen pulse, a phenomenon often observed in endurance athletes throughout their competitive careers.

The effect of ischemic preconditioning on repeated sprint cycling performance: a randomized crossover study.

Ischemic preconditioning (IPC) has been suggested to improve exercise performance by 1-8%. Prior research concerning its impact on short-duration exercises, such as sprints, has been limited and yielded conflicting results. The aim of this study, which included a non-occlusion-based placebo control, was to determine whether IPC improves repeated sprint performance in a manner that accounted for psychophysiological effects. Twenty-two healthy males participated in this study, which employed a randomized crossover design. Following the 10-min baseline period, participants received intervention under four different conditions: 1) no-intervention control (CON); 2) non-occlusion-based placebo control (SHAM); 3) remote IPC (RIPC); and 4) local IPC (LIPC). Participants then performed a standardized repeated sprint cycling (5×10s maximal cycling sprint, separated by a 40-s rest in each set). Repeated sprint performance, as indexed by average power output, peak power output, and total work, the improvement was observed in the RIPC and LIPC during the initial phase (set 1-3) when compared with CON (P<0.05). SHAM condition also showed an increase in peak power output in the set 1 (CON 9.97±1.05 vs. SHAM 10.30±1.13 w/kg, P<0.05), which may represent a psychophysiological component in the IPC-induced improvement. Higher lactate concertation was found in the SHAM and LIPC groups, than in the CON group, 5 minutes after the exercise (CON 15.72±0.68 vs. SHAM 16.82±0.41 vs. LIPC 17.19±0.39 mmol/L, P<0.0001 for both, respectively). In conclusion, LIPC enhanced repeated sprint cycling performance during the initial phase, beyond what could be accounted for entirely by a psychophysiological effect. The improvement associated with RIPC, however, did not surpass the effect of a placebo intervention.

Predicting Future Athletic Performance in Young Female Road Cyclists Based on Aerobic Fitness and Hematological Variables.

This study aimed to determine whether the initial levels of aerobic fitness and hematological variables in young female road cyclists are related to their athletic performance development during their careers. Results of graded exercise tests on a cycle ergometer and total hemoglobin mass (tHb-mass) measurements were analyzed in 34 female road cyclists (age 18.6 [1.9]y). Among them, 2 groups were distinguished based on their competitive performance (Union Cycliste Internationale world ranking) over the following 8years. Areas under the curve in receiver-operating-characteristic curves were calculated as indicators of elite-performance prediction. Initial graded exercise test variables (peak power, peak oxygen uptake, and power at 4mmol/L blood lactate) were not significantly different in elite (n = 13) versus nonelite (n = 21) riders. In contrast, elite riders had higher tHb-mass expressed either in absolute measures(664 [75] vs 596 [59]g, P = .006) or normalized to body mass (11.2 [0.8] vs 10.3 [0.7]g/kg, P = .001) and fat-free mass (14.4 [0.9] vs 13.1 [0.9]g/kg, P < .001). Absolute and relative erythrocyte volumes were significantly higher in elite subjects (P ranged from < .001 to .006). Of all the variables analyzed, the relative tHb-mass had the highest predictive ability to reach the elite level (area under the curve ranged from .82 to .85). Measurement of tHb-mass can be a helpful tool in talent detection to identify young female road cyclists with the potential to reach the elite level in the future.

Variable-stiffness prosthesis improves biomechanics of walking across speeds compared to a passive device

Ankle push-off power plays an important role in healthy walking, contributing to center-of-mass acceleration, swing leg dynamics, and accounting for 45% of total leg power. The majority of existing passive energy storage and return prostheses for people with below-knee (transtibial) amputation are stiffer than the biological ankle, particularly at slower walking speeds. Additionally, passive devices provide insufficient levels of energy return and push-off power, negatively impacting biomechanics of gait. Here, we present a clinical study evaluating the kinematics and kinetics of walking with a microprocessor-controlled, variable-stiffness ankle-foot prosthesis (945 g) compared to a standard low-mass passive prosthesis (Ottobock Taleo, 463 g) with 7 study participants having unilateral transtibial amputation. By modulating prosthesis stiffness under computer control across walking speeds, we demonstrate that there exists a stiffness that increases prosthetic-side energy return, peak power, and center-of-mass push-off work, and decreases contralateral limb peak ground reaction force compared to the standard passive prosthesis across all evaluated walking speeds. We demonstrate a significant increase in center-of-mass push-off work of 26.1%, 26.2%, 29.6% and 29.9% at 0.75 m/s, 1.0 m/s, 1.25 m/s, and 1.5 m/s, respectively, and a significant decrease in contralateral limb ground reaction force of 3.1%, 3.9%, and 3.2% at 1.0 m/s, 1.25 m/s, and 1.5 m/s, respectively. This study demonstrates the potential for a quasi-passive microprocessor-controlled variable-stiffness prosthesis to increase push-off power and energy return during gait at a range of walking speeds compared to a passive device of a fixed stiffness.

Engineering Partially Oxidized Gold via Oleylamine Modifier as a High-Performance Anode Catalyst in a Direct Borohydride Fuel Cell.

Direct borohydride fuel cell (DBFC) is considered a promising energy storage device due to its high theoretical cell voltage and energy density. For DBFC, an Au catalyst has been used as an anode for achieving an ideal eight-electron reaction. However, the poor activity of the Au catalyst for borohydride oxidation reaction (BOR) limits its large-scale application because of the weak BH4- adsorption. We found, by density functional theory calculations, that the adsorption of BH4- on the oxidized Au surface is stronger than that on the metallic Au surface, which can promote the process of the oxidation of BH4- to *BH3 during the BOR. Here, we reported an oleylamine-modified partially oxidized Au supported on carbon powder (AuC-OLA) with a stable oxidation state. The obtained catalyst delivered a high peak power density of 143 mW/cm2, which is 2 times higher than that of a commercial 40% AuC (Pretemek). The in situ Fourier transform infrared studies showed that the activity of AuC-OLA for BOR is ascribed to the enhanced adsorption for BH4- on the partially oxidized Au surface. These findings will promote the reasonable design of efficient Au electrocatalysts for DBFCs.

Ultrawide dual contact strip fabricated quantum cascade lasers with reduced beam divergence angle

Power scaling through the broadening of the laser core in Quantum Cascade Lasers can extract greater average power from devices at the cost of mode quality. To improve transverse mode quality for ultrawide (&gt;100 µm) devices, a dual contact strip waveguide geometry is designed and demonstrated, utilizing a reduced top cladding thickness, and modifying the gold electrical epi-side contact to affect mode competition. A 200 µm wide Dual Contact Strip laser emitting at 4.6 µm wavelength is measured with far-field full-width half-maximum of 2.5° in a central single lobe. Relative an identical waveguide without the dual contact strips, peak power was 30% higher and far field was 32% narrower. This demonstrates the ability to achieve fundamental-like far field behavior in very broad quantum cascadel asers while potentially simplifying the fabrication method.

Spin occupancy regulation of the Pt d-orbital for a robust low-Pt catalyst towards oxygen reduction

Disentangling the limitations of O-O bond activation and OH* site-blocking effects on Pt sites is key to improving the intrinsic activity and stability of low-Pt catalysts for the oxygen reduction reaction (ORR). Herein, we integrate of PtFe alloy nanocrystals on a single-atom Fe-N-C substrate (PtFe@FeSAs-N-C) and further construct a ferromagnetic platform to investigate the regulation behavior of the spin occupancy state of the Pt d-orbital in the ORR. PtFe@FeSAs-N-C delivers a mass activity of 0.75 A mgPt−1 at 0.9 V and a peak power density of 1240 mW cm−2 in the fuel-cell, outperforming the commercial Pt/C catalyst, and a mass activity retention of 97%, with no noticeable current drop at 0.6 V for more than 220 h, is attained. Operando spectroelectrochemistry decodes the orbital interaction mechanism between the active center and reaction intermediates. The Pt dz2 orbital occupation state is regulated to t2g6eg3 by spin-charge injection, suppressing the OH* site-blocking effect and effectively inhibiting H2O2 production. This work provides valuable insights into designing high-performance and low-Pt catalysts via spintronics-level engineering.

Evaluation Method of Magnetic Field Stability for Robotic Arc Welding Based on Sample Entropy and Probability Distribution

In this study, we analyzed the arc magnetic field to assess the stability of the arc welding process, particularly in robotic welding where direct measurement of welding current is challenging, such as under water. The characteristics of the magnetic field were evaluated based on low-frequency fluctuations and the symmetry of the signals. We used double-wire pulsed MIG welding for our experiments, employing Q235 steel with an 8.0 mm thickness as the material. Key parameters included an average voltage of 19.8 V, current of 120 A, and a wire feeding speed of 3.3 m/min. Our spectral analysis revealed significant correlations between welding stability and factors such as the direct current (DC) component and the peak power spectral density (PSD) frequency. To quantify this relationship, we introduced a novel approach using sample entropy and mix sample entropy (MSE) as new evaluation metrics. This method achieved a notable accuracy of 88%, demonstrating its effectiveness in assessing the stability of the robotic welding process.

Design of X-Band Circulator and Isolator for High-Peak-Power Applications

This paper presents a design of a X-band circulator–isolator for handling high-peak-power applications. The device consists of two cascade-connected ferrite circulators, with one dedicated to transmission and the other to small-signal reception coupled with high-power signal isolation. To improve the power capacity, a layer of poly-tetra fluoroethylene (PTFE) film is placed above and below the circulator’s and the isolator’s center conductors. Measurement results show that the device is capable of withstanding a peak power of 7000 W, with an insertion loss of &lt;0.3 dB at the transmitting port. Similarly, it sustains a peak power of 6000 W with an insertion loss of &lt;0.5 dB at the reception port. Moreover, the proposed design achieved isolation between the transmitting and receiving ends of &gt;20 dB with a VSWR &lt; 1.2 at each port. Thermal analysis shows that the maximum relative ambient temperature rise is 15.11 ∘C. These findings show that the proposed device achieves low-loss transmission of high-peak-power signals in the transmit channel and reverse isolation of high-peak-power signals in the receive channel.

Sixweeks of localized passive heat therapy elicits some exercise-like improvements in resistance artery function.

The purpose of this study was to examine the effects of 6weeks of localized, muscle-focused (quadriceps femoris) passive heat therapy (PHT) on resistance artery function, exercise haemodynamics and exercise performance relative to knee extension (KE) exercise training (EX). We randomized 34healthy adults (ages 18-36; n=17 female, 17male) to receive either PHT or sham heating sessions (120min, 3days/week), or EX (40min, 3days/week) over 6weeks. Blood flow was assessed with Doppler ultrasound of the femoral artery during both passive leg movement (PLM) and a KE graded exercise test. Muscle biopsies were taken from the vastus lateralis at baseline and after 6weeks. Peak blood flow during PLM increased to the same extent in both the EX (∼10.5% increase, P=0.009) and PHT groups (∼8.5% increase, P=0.044). Peak flow during knee extension exercise increased in EX (∼19%, P=0.005), but did not change in PHT (P=0.523) and decreased in SHAM (∼7%, P=0.020). Peak vascular conductance during KE increased by ∼25% in EX (P=0.030) and PHT (P=0.012). KE peak power increased in EX by ∼27% (P=0.001) but did not significantly change in PHT and SHAM groups. Expression of endothelial nitric oxide synthase increased significantly in both EX (P=0.028) and PHT (P=0.0095), but only EX resulted in increased angiogenesis. In conclusion, 6weeks of localized PHT improved resistance artery function at rest and during exercise to the same extent as exercise training but did not yield significant improvements in performance. KEY POINTS: Many for whom exercise would be most beneficial are either unable to exercise or have a very low exercise tolerance. In these cases, an alternative treatment to combat declines in resistance artery function is needed. We tested the hypothesis that passive heat therapy (PHT) would increase resistance artery function, improve exercise haemodynamics and enhance exercise performance compared to a sham treatment, but less than aerobic exercise training. This report shows that 6weeks of localized PHT improved resistance artery function at rest and during exercise to the same extent as exercise training but did not improve exercise performance. Additionally, muscle biopsy analyses revealed that endothelial nitric oxide synthase expression increased in both PHT and exercise training groups, but only exercise resulted in increased angiogenesis. Our data demonstrate the efficacy of applying passive heat as an alternative treatment to improve resistance artery function for those unable to receive the benefits of regular exercise.

Harnessing the Trade‐Off between CoFe/Fe3C Interfacial Junction with Unparalleled Potential Gap of 0.58 V for Reversible Oxygen Electrocatalysis: Application toward Liquid and Solid‐State Zn‐Air Batteries

AbstractEffective integration of multiple active moieties and strategic engineering of coordinated interfacial junctions are crucial for optimizing the reaction kinetics and intrinsic activities of heterogeneous electrocatalysts. Herein, a simple integrated heterostructure of biphasic Co0.7Fe0.3/Fe3C embedded on in situ grown N‐doped carbon sheets is constructed. Rationally designed CoFe/Fe3C‐T2 owns more accessible active sites and interfacial junction effects, cooperatively boosting the electron and mass transfer, needed for multifunctional electrocatalysis. Leveraging the synergistic effect of dual active sites, CoFe/Fe3C‐T2 demonstrates outstanding oxygen electrocatalytic activity in alkaline medium with an ultra‐low potential gap of 0.58 V, surpassing the recently available state‐of‐the‐art catalysts. Moreover, CoFe/Fe3C‐T2 air‐electrode achieves a high peak power density of 249 mW cm−2, a large specific capacity of 808 mAh g−1 and excellent cycling stability for aqueous Zn‐air batteries. Remarkably, the solid‐state flexible ZAB also exhibits satisfactory performance, showcasing an open‐circuit voltage of 1.43 V and a peak power density of 66 mW cm−2. These outstanding results push this catalyst to the top of the list of non‐noble metal‐based electrode materials. This work offers a viable method for using the active‐site‐uniting strategy to create double‐active‐site catalysts, which may find real‐time applications in energy conversion/storage devices.

Simulation study on the dynamic characteristics of natural circulation coupled phase change material for equal height difference passive containment cooling system

The passive containment cooling system (PCCS) plays a significant role in ensuring the safety of nuclear power plants. To further reduce peak pressure in the containment during a loss of coolant accident (LOCA), phase change materials (PCMs) are utilized to improve the system’s cooling effectiveness. The dynamic simulation model of PCCS has been developed using Apros software. This article focuses on examining the system’s dynamic characteristics related to various tube startup methods and comparatively analyzing the impact of different PCM thicknesses on heat transfer capacity. The results indicate that post-accident, PCM significantly suppresses peak pressure in the containment. Under the full tube startup method with 4 mm PCM, the peak pressure decreases to 1.75 MPa, whereas under the empty tube startup method, it is reduced to 1.69 MPa. With natural circulation empty tube startup method, PCM can reduce pressure change intensity in the containment but negatively affects natural circulation heat transfer. Although the full tube startup method underperforms the empty tube startup method on suppressing peak pressure, PCM can positively affect natural circulation heat transfer in the early stages of the accident. Empty tube startup offers the advantages of higher heat transfer capacity and lighter weight, making it the optimal choice for ocean nuclear platforms. Additionally, the higher peak power of PCM heat transfer under the empty tube startup method indicates that system can withstand larger thermal shocks.

Rational construction of noble-metal-free fuel cell-supercapacitor hybrid power source using polyaniline electrode as both anode and cathode

The integration of fuel cell device and supercapacitor device into a singular hybrid power source at the electrode level can make the best use of the advantages of each individual device and more importantly, eliminate the energy loss by virtue of the conversion of chemical energy to electric energy on electrocatalyst material and the storage of electric energy on energy storage material simultaneously. To avoid the use of noble metal electrocatalyst and exploit the dual electrocatalytic and capacitive function of polyaniline, a noble-metal-free fuel cell-supercapacitor hybrid power source employing polyaniline electrode as both anode and cathode is rationally constructed. Based on electrochemical in-situ Raman spectroscopy, this work proposes that the open circuit potential (OCP) of polyaniline electrode is a simple and quick indicator of the redox state of polyaniline. After carefully selecting the fuel and carbon-based support, it is found that the ascorbic acid fuel and the carbon fiber cloth supported polyaniline contributes to the lowest OCP threshold in the anode, and thus the fastest self-charge and largest stabilized open circuit voltage of hybrid power source. The hybrid power source can be self-charged to 0.32 V and yield a peak power density of 0.21 mW cm−2.

Short-length nanosecond pulsed 1.653-μm DBR fiber Raman laser oscillator fabricated by femtosecond laser direct-writing

We demonstrate a nanosecond pulsed 1.653-μm fiber Raman laser (FRL) oscillator in a short-length distributed Bragg reflector (DBR) cavity made by femtosecond laser direct-writing technique. The DBR FRL cavity is composed of commercial ultrahigh NA germanium-doped silica fiber with a short length of 10 m and a pair of fiber Bragg gratings (FBGs). The FBGs were directly inscribed on the ends of the Raman gain fiber, using femtosecond-laser point-by-point (PbP) writing method. A home-made 1.55-μm nanosecond fiber laser source was used as the pump of the FRL. 1.653-μm nanosecond pulsed laser oscillation with maximum average output power of 125 mW (corresponding to peak power of 6.6 W), 3 dB linewidth of ≤ 0.15 nm, and slope efficiency of 48 % was obtained under 1.55-μm pump with optimized repetition rate of 10 MHz. The optical signal-to-noise-ratio (OSNR) of the 1.653-μm narrow-linewidth Raman lasing is above 70 dB. The short-length DBR FRL output exhibits decently high degree of polarization (DOP) and high degree of linear polarization (DOLP) above 80 % in 3-hour period, benefitted from the birefringent FBGs made by femtosecond laser direct-writing method. It is expected that by further reducing the cavity length to < 1 m, the 1.653-μm DBR FRL oscillator made by femtosecond laser direct-writing method is promising as single-frequency narrow-linewidth, highly linearly polarized, high-OSNR laser sources for high-sensitivity CH4 gas detection.

Acute inflammatory response following lower-and upper-body Wingate anaerobic test in elite gymnasts in relation to iron status

Introduction: Artistic gymnastics is one of the most demanding sports disciplines, with the athletes demonstrating extremely high levels of explosive power and strength. Currently, knowledge of the effect of gymnastic training adaptation on exercise-induced inflammatory response is limited. The study aimed to evaluate inflammatory response following lower- and upper-body high-intensity exercise in relation to the iron status in gymnasts and non-athletes. Methods: Fourteen elite male artistic gymnasts (EAG, 20.6 ± 3.3 years old) and 14 physically active men (PAM, 19.9 ± 1.0 years old) participated in the study. Venous blood samples were taken before and 5 min and 60 min after two variants of Wingate anaerobic test (WAnT), upper-body and lower-body WAnT. Basal iron metabolism (serum iron and ferritin) and acute responses of selected inflammatory response markers [interleukin (IL) 6, IL-10, and tumour necrosis factor α] were analysed.Results: EAG performed significantly better during upper-body WAnT than PAM regarding relative mean and peak power. The increase in IL-6 levels after upper-body WAnT was higher in EAG than in PAM; the opposite was observed after lower-body WAnT. IL-10 levels were higher in EAG than in PAM, and tumour necrosis factor α levels were higher in PAM than those in EAG only after lower-body WAnT. The changes in IL-10 correlated with baseline serum iron and ferritin in PAM.Discussion: Overall, gymnastic training is associated with the attenuation of iron-dependent post-exercise anti-inflammatory cytokine secretion.

Highly Moisture-Resistant Flexible Thin-Film-Based Triboelectric Nanogenerator for Environmental Energy Harvesting and Self-Powered Tactile Sensing.

Triboelectric nanogenerator (TENG) has been demonstrated as a sustainable energy utilization method for waste mechanical energy and self-powered system. However, the charge dissipation of frictional layer materials in a humid environment severely limits their stable energy supply. In this work, a new method is reported for preparing polymer film as a hydrophobic negative friction material by solution blending poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) and polyvinyl chloride (PVC), doping with titanium dioxide (TiO2) nanoparticles, and further surface patterning modification. The P-TENG composed of the PVDF-HFP/PVC/TiO2 composite film with optimized hydrophobic performance (WCA = 124°) achieved an output voltage of 235 V and a short-circuit current of 35 μA, which is approximately three times that of the bare PVDF-HFP-based TENG. Under charge excitation, the transferred charge of the P-TENG can reach 35 nC. When the external load resistance is 5.5 MΩ, the output peak power density can reach 1.4 W m-2. Meanwhile, the hydrophobic surface layer with a rough surface structure enables the device to overcome the influence of water molecules on charge transfer in a humid environment, quickly recover, and maintain a high output. The P-TENG can effectively monitor finger flexibility and strength and realize real-time evaluation of the exercise state and hand fatigue of the elderly and rehabilitation trainers. It has broad application prospects in self-powered intelligent motion sensing, soft robotics, human-machine interaction, and other fields.

Valorization of Food Waste: Utilizing Natural Porous Materials Derived from Pomelo-Peel Biomass to Develop Triboelectric Nanogenerators for Energy Harvesting and Self-Powered Sensing.

Food waste is an enormous challenge, with implications for the environment, society, and economy. Every year around the world, 1.3 billion tons of food are wasted or lost, and food waste-associated costs are around $2.6 trillion. Waste upcycling has been shown to mitigate these negative impacts. This study's optimized pomelo-peel biomass-derived porous material-based triboelectric nanogenerator (PP-TENG) had an open circuit voltage of 58 V and a peak power density of 254.8 mW/m2. As porous structures enable such triboelectric devices to respond sensitively to external mechanical stimuli, we tested our optimized PP-TENG's ability to serve as a self-powered sensor of biomechanical motions. As well as successfully harvesting sufficient mechanical energy to power light-emitting diodes and portable electronics, our PP-TENGs successfully monitored joint motions, neck movements, and gait patterns, suggesting their strong potential for use in healthcare monitoring and physical rehabilitation, among other applications. As such, the present work opens up various new possibilities for transforming a prolific type of food waste into value-added products and thus could enhance long-term sustainability while reducing such waste.

Exploring a New Class of PVDF/3‐Aminopropyltriethoxysilane (core) and 2,2‐Bis(hydroxymethyl)butyric Acid (monomer)‐Based Hyperbranched Polyester Hybrid Fibers by Electrospinning Technique for Enhancing Triboelectric Performance

AbstractWith the rapid advancement in sensor technologies, triboelectric nanogenerators (TENGs) have emerged as a promising sustainable power source for intelligent electronics. Herein, fabricated a novel 3‐aminopropyltriethoxysilane (core) and 2,2‐bis(hydroxymethyl)butyric acid (monomer)‐based hyperbranched polyester by facile single‐step polycondensation technique generation 2 (Si‐HBP‐G2). Further, a new class of polyvinylidene fluoride (PVDF) and different weight percentages (0, 5, 10, 15, and 20 wt%) of Si‐HBP‐G2 hybrid fiber blends are prepared by traditional electrospinning technique. The as‐prepared Si‐HBP‐G2 and its blends are well characterized using SEM/EDS, FTIR, NMR, and XRD studies. The influence of Si‐HBP‐G2 content on triboelectric performance in terms of the open circuit potential (VOC) and short circuit current (ISC) is evaluated using aluminum (Al) as a counter electrode. Among them, 15 wt% of Si‐HBP‐G2/PVDF hybrid fiber mat (PG2‐15) exhibits superior electrical performance. Which is almost increased 5.9 times (22–130 V) of VOC and 4.9 times (0.71–3.5 µA) of ISC than PVDF fiber mate. These results reveal the significance of Si‐HBP‐G2 in the triboelectric performance. The optimized TENG device (PG2‐15/Al‐TENG) exhibits a peak power density of 0.2 Wm−2 at 100 MΩ external load. Finally, the PG2‐15/Al‐TENG practically demonstrates real‐time application energy harvesting applications such as powering 100 LEDs and a stopwatch.

Assessing the Post-Activation Performance Enhancement of Upper Limbs in Basketball Athletes: A Sensor-Based Study of Rapid Stretch Compound and Blood Flow Restriction Training

Objective: This study introduces a novel methodology combining rapid stretch compound training with blood flow restriction (BFR) to investigate post activation performance enhancement (PAPE) in basketball players, a field that has been predominantly explored for lower limbs. We aimed to assess the efficacy of this combined approach on upper limb muscle performance in athletes. Methods: We employed a randomized, self-controlled crossover trial with ten male basketball players. The bench press throw (BPT) served as the primary metric, with players undergoing four interventions post-baseline: (1) STR—plyometric training; (2) BFR—blood flow restriction; (3) COMB—STR integrated with BFR; and (4) CON—control. Innovatively, we utilized an intelligent tracking sensor to precisely measure peak power (PP), peak velocity (PV), mean power (MP), and mean velocity (MV) at 4, 8, and 12 min post-intervention, providing a detailed temporal analysis of PAPE. Results: The COMB intervention demonstrated superior PAPE effects at 4 min, significantly outperforming STR and BFR alone and the control group across all measured indices (p &lt; 0.05). Notably, the COMB group maintained these improvements for PV, PP, and H up to 12 min post-intervention, suggesting a prolonged effect. Conclusion: (1) The COMB stimulation has been shown to successfully induce PAPE more effectively than STR and BFR modality alone. (2) It appears that the optimal effects of PAPE are achieved within 4 min of exercising under this COMB. By the 12 min mark, only the COMB group continued to show significant improvements in PV, PP, and H compared to both the baseline and the CON group, while the effects in the STR and BFR groups further diminished. This suggests that although the PAPE effect is maintained over time, its optimal performance may peak at the 4 min mark and then gradually weaken as time progresses.

Assessing the Post-Activation Performance Enhancement of Upper Limbs in Basketball Athletes: A Sensor-Based Study of Rapid Stretch Compound and Blood Flow Restriction Training

Objective: This study introduces a novel methodology combining rapid stretch compound training with blood flow restriction (BFR) to investigate post activation performance enhancement (PAPE) in basketball players, a field that has been predominantly explored for lower limbs. We aimed to assess the efficacy of this combined approach on upper limb muscle performance in athletes. Methods: We employed a randomized, self-controlled crossover trial with ten male basketball players. The bench press throw (BPT) served as the primary metric, with players undergoing four interventions post-baseline: (1) STR—plyometric training; (2) BFR—blood flow restriction; (3) COMB—STR integrated with BFR; and (4) CON—control. Innovatively, we utilized an intelligent tracking sensor to precisely measure peak power (PP), peak velocity (PV), mean power (MP), and mean velocity (MV) at 4, 8, and 12 min post-intervention, providing a detailed temporal analysis of PAPE. Results: The COMB intervention demonstrated superior PAPE effects at 4 min, significantly outperforming STR and BFR alone and the control group across all measured indices (p &lt; 0.05). Notably, the COMB group maintained these improvements for PV, PP, and H up to 12 min post-intervention, suggesting a prolonged effect. Conclusion: (1) The COMB stimulation has been shown to successfully induce PAPE more effectively than STR and BFR modality alone. (2) It appears that the optimal effects of PAPE are achieved within 4 min of exercising under this COMB. By the 12 min mark, only the COMB group continued to show significant improvements in PV, PP, and H compared to both the baseline and the CON group, while the effects in the STR and BFR groups further diminished. This suggests that although the PAPE effect is maintained over time, its optimal performance may peak at the 4 min mark and then gradually weaken as time progresses.