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This study evaluated whether Speed Stacking elicits sufficient physiological intensity to meet moderate-to-vigorous physical activity (MVPA) thresholds in youth, using portable indirect calorimetry and accelerometry. Fifty-four participants (age = 14.01 ± 5.48 years; 46.3% female) completed four randomized activity conditions: Rest, Speed Stacking, Running, and Speed Stack + Run, each lasting five minutes. Participants wore a COSMED K5 metabolic system, hip and wrist ActiGraph GT3X+ accelerometers, and a heart rate monitor. Energy expenditure (METs), accelerometer counts, perceived exertion, and fun were analyzed using repeated measures ANOVAs and Cohen's Kappa for method agreement. In both prepubescent and pubescent groups, Speed Stacking alone did not meet the specific MET thresholds for MVPA. However, the hybrid Stack + Run condition significantly increased METs (up to 5.1 ± 1.2 in prepubescents). Cohen's Kappa revealed poor agreement between MET-based and accelerometer-based intensity categorical classifications across all conditions. Participants, especially younger children, reported Speed Stacking as fun but minimally effortful. Speed Stacking alone fails to meet key pedagogical criteria for physical education, particularly those related to maximizing activity time and MVPA engagement. Given the limited time available in PE settings, alternative activities with higher energy expenditure may offer a more efficient use of instructional time. However, when integrated with movement-based tasks, Speed Stacking can be adapted to better support physical and educational outcomes.
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http://dx.doi.org/10.1080/02701367.2025.2549064 | DOI Listing |
J Phys Chem Lett
September 2025
Materials Genome Institute, School of Materials and Energy, Yunnan University, Kunming 650091, P. R. China.
Magnetic two-dimensional van der Waals (vdWs) materials hold potential applications in low-power and high-speed spintronic devices due to their degrees of freedom such as valley and spin. In this Letter, we propose a mechanism that uses stacking engineering to control valley polarization (VP), ferroelectricity, layer polarization (LP), and magnetism in vdWs bilayers. Through first-principles calculations, we predict that the T-VSI monolayer is a magnetic semiconductor with a sizable VP.
View Article and Find Full Text PDFTheor Appl Genet
September 2025
Queensland Alliance for Agriculture and Food Innovation, University of Queensland, Brisbane, Australia.
Stacking desirable haplotypes across the genome to develop superior genotypes has been implemented in several crop species. A major challenge in Optimal Haplotype Selection is identifying a set of parents that collectively contain all desirable haplotypes, a complex combinatorial problem with countless possibilities. In this study, we evaluated the performance of metaheuristic search algorithms (MSAs)-genetic algorithm (GA), differential evolution (DE), particle swarm optimisation (PSO), and simulated annealing (SA) for optimising parent selection under two genotype building (GB) objectives: Optimal Haplotype Selection (OHS) and Optimal Population Value (OPV).
View Article and Find Full Text PDFPlanta
September 2025
Agroscope, Research Division Plant Breeding, Müller-Thurgau-Strasse 29, 8820, Waedenswil, Switzerland.
Using the "LIFT" method can halve generation time to two years, thereby reducing the breeding cycle by 50%, and accelerate the development of disease-resistant apple cultivars for sustainable production. Good sources of resistance to pests and pathogens are often found in wild relatives or ornamental apples, which are mainly small-fruited and poor-tasting. Introgressing these resistance genes via classical breeding into new apple cultivars with good tree and fruit qualities requires a series of four to five pseudo-backcrosses, which takes at least 25 years.
View Article and Find Full Text PDFPolymers (Basel)
August 2025
Department of Airframe and Powerplant Maintenance, Faculty of Aeronautics and Astronautics, Kocaeli University, Kocaeli 41001, Türkiye.
Drilling-induced damage in fiber-reinforced polymer composite materials was measured excavating four laminates, basalt (B), glass (G) and their two sandwich type hybrids (BGB, GBG), with 6 mm twist drills at 1520 revolutions per minute and 0.10 mm rev under dry running with an uncoated high-speed steel (HSS-R), grind-coated high-speed steel (HSS-G) or physical vapor deposition-coated (high-speed steel coated with Titanium Nitride (TiN) and Titanium Aluminum Nitride (TiAlN)) drill bits. The hybrid sheets were deliberately incorporated to clarify how alternating basalt-glass architectures redistribute interlaminar stresses during drilling, while the hard, low-friction TiN and TiAlN ceramic coatings enhance cutting performance by forming a heat-resistant tribological barrier that lowers tool-workpiece adhesion, reduces interface temperature, and thereby suppresses thrust-induced delamination.
View Article and Find Full Text PDFRes Q Exerc Sport
August 2025
The Citadel.
This study evaluated whether Speed Stacking elicits sufficient physiological intensity to meet moderate-to-vigorous physical activity (MVPA) thresholds in youth, using portable indirect calorimetry and accelerometry. Fifty-four participants (age = 14.01 ± 5.
View Article and Find Full Text PDF