35 research outputs found

    The effect of physical activity on the perception of body image and well-being during aging

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    Problem Statement: Physical activity levels have been positively associated with mental and physical wellbeing. Nevertheless, associations between physical activity levels, which decrease with aging, and body image perception and indices of psycho-physical well-being have never been studied in adult and elderly subjects as a function of aging. Approach: This observational study was carried out in several provinces and regions of Italy. Information was collected from 192 men and 260 women between 50 and 98 years using a questionnaire on place of residence, physical activity level, perceived well-being and body image. Purpose: This study aimed to assess the influence of the level of physical activity on perceptions of body image and well-being in adult and elderly subjects. Results: Physical activity levels were positively associated with body image perception. Interactions between physical activity levels and the other investigated variables showed no significant effect on body image. Hence, the main effect of physical activity on body image does not vary according to the subject’s age, place of residence (rural or urban), kind of job (active or sedentary) or educational level. The well-being index was not significantly associated with either physical activity levels or the other variables investigated in this study. Conclusions: Physical activity levels are positively correlated with the body image perception, and high levels of physical activity are associated with more accurate perceptions of body image. The effect of physical activity is not influenced by different individual characteristics; hence, increasing levels of physical activity could improve body image perception across a broad range of subjects. On the other hand, the well-being index was not influenced by either physical activity levels or the other characteristics examined in this investigation. Additional experimental studies are needed to develop a specific intervention to improve the well-being and body image perception in adults and elderly subjects

    Effect of steady-state aerobic exercise intensity and duration on the relationship between reserves of heart rate and oxygen uptake

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    Background. The percentages of heart rate (%HRR) or oxygen uptake (%V̇O2R) reserve are used interchangeably for prescribing aerobic exercise intensity due to their assumed 1:1 relationship, although its validity is debated. This study aimed to assess if %HRR and %V̇O2R show a 1:1 relationship during steady-state exercise (SSE) and if exercise intensity and duration affect their relationship. Methods. Eight physically active males (age 22.6±1.2 years) were enrolled. Pre-exercise and maximal HR and V̇O2 were assessed on the first day. In the following 4 days, different SSEs were performed (running) combining the following randomly assigned durations and intensities: 15 min, 45 min, 60% HRR, 80% HRR. Post-exercise maximal HR and V̇O2 were assessed after each SSE. Using pre-exercise and post-exercise maximal values, the average HR and V̇O2 of the last 5 min of each SSE were converted into percentages of the reserves (%RES), which were computed in a 3-way RM-ANOVA (α=0.05) to assess if they were affected by the prescription parameter (HRR or V̇O2R), exercise intensity (60% or 80% HRR), and duration (15 or 45 min). Results. The %RES values were not affected by the prescription parameter (p=0.056) or its interactions with intensity (p=0.319) or duration and intensity (p=0.117), while parameter and duration interaction was significant (p=0.009). %HRRs and %V̇O2Rs did not differ in the 15-min SSEs (mean difference [MD]=0.7 percentage points, p=0.717), whereas %HRR was higher than %V̇O2R in the 45-min SSEs (MD=6.7 percentage points, p=0.009). Conclusion. SSE duration affects the %HRR-%V̇O2R relationship, with %HRRs higher than %V̇O2Rs in SSEs of longer duration

    Il talento nella “mente” dell’atleta di resistenza. Utilizzo del modello SFERA nella valutazione della preparazione mentale del ciclista

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    In endurance sports such as cycling, the preparation and mental predisposition of the athlete are essential to overcomeand go beyond the fatigue and pain that are inalienable from the sport itself. Therefore, the mental componentis correlated not only with the performances during the competitions, but also with the ability to train at best.Consequently, the mental component seems to be essential for the athlete’s talent, which suggests a strong correlationbetween the two parameters. Recently, the SFERA mental training model is used in some endurance sports.The observational study aims to assess whether in 30 non-professional cyclists (16-21 years) the factors of theSFERA (i.e., synchronization, strengths, energy, rhythm and activation) are in balance. The psychological componentswere evaluated by means of a specific questionnaire (SFERA-Q).Differences were found among the several factors within the SFERA. The rhythm is the dominant factor, having thehighest values, while the synchronization and activation have the lowest values among the factors of the SFERA.In conclusion, this study showed that, in young non-professional cyclists, there was no optimal mental conditionfor achieving maximal performance, which makes us assume that a psychological preparation aimed at rebalancingthose factors can lead to an optimal mental state and, consequently, to better performances.Negli sport di resistenza come il ciclismo la preparazione e predisposizione mentale dell’atleta è essenziale persuperare e andare oltre la fatica e dolore che sono inalienabili dallo sport stesso. Quindi la componente mentaleè correlata non solo con le prestazioni durante le competizioni, ma anche con la capacità di allenarsi al meglio. Diconseguenza la componente mentale sembra essere imprescindibile dal talento dell’atleta, il che suggerisce unaforte correlazione tra i due parametri.Negli ultimi anni il modello di allenamento mentale SFERA viene utilizzato in alcuni sport di resistenza.Lo studio, di natura osservazionale, ha come obiettivo di valutare se in 30 ciclisti non professionisti (16-21 anni) ifattori della SFERA (i.e., sincronia, punti di forza, energia, ritmo e attivazione) sono in equilibrio tra loro. Le variecomponenti psicologiche sono state valutate tramite uno specifico questionario (SFERA-Q).Sono emerse differenze tra i vari fattori all’interno della SFERA. Il ritmo risulta il fattore dominante, con i valori piùelevati, mentre la sincronia e attivazione presentano valori minori tra i fattori della SFERA.In conclusione, questo studio ha mostrato che, in giovani ciclisti non professionisti, non è presente una condizionementale ottimale ai fini del raggiungimento delle massime prestazioni. Questo ci fa presupporre che unapreparazione psico-pedagogica mirata al riequilibro tra i vari fattori possa portare ad uno stato mentale ottimalee, di conseguenza a prestazioni migliori

    La percezione fisica di sé negli scolari adolescenti: Ruolo della costituzione fisica e del livello di attività fisica

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    Physical self-perception depends on body weight, gender, but also to physical exercise. It is not well understood, however, whether the effects of the latter can be attributed to the level of physical activity or to the resulting physical fitness. Therefore, this study investigated the effects of both physicalactivity level and physical fitness on the physical self-perception and its relationship with gender and body weight in adolescent pupils. The fitness level of 188 adolescents aged 12-16 years old was assessed through a test battery, while the “Physical Activity Questionnaire for Adolescents” and the “Physical Self-Description Questionnaire Short” were administered to assess physical activity level and physical self-perception, respectively. The effects of gender and body weight on physical self-perception was evaluated using the analysis of variance with physical activity level and physical fitness as covariates. Results showed that overweight reduces the overall physical self-perception.Furthermore, the physical self-perception is generally higher in males than in females even without differences in either physical activity level or physical fitness.La percezione di sé è influenzata dalla costituzione corporea, dal sesso, e dall’esercizio fisico. Non è chiaro, però, se gli effetti dell’esercizio derivino dal livello di attività fisica praticata o dal miglioramento delle capacità fisiche che esso determina. Pertanto questo studio ha indagato l’effetto, sia del livello di attività fisica che delle capacità fisiche sulla percezione fisica di sé, in funzione del sesso e della costituzione corporea, in studenti adolescenti. Il livello generale delle capacità fisiche di 188 adolescenti tra i 12 ed i 16 anni è stato valutato tramite una batteria di test motori, il livello di attività fisica è stato misurato con il questionario Physical Activity Questionnaire for Adolescents, mentre la percezione fisica di sé è stata valutata con il questionario Physical Self-Description Questionnaire Short. L’effetto del sesso e della costituzione fisica sono stati indagati tramite analisi della varianza considerando come covariate il livello di attività fisica e le capacità fisiche. I risultati evidenziano che essere in sovrappeso diminuisce la considerazione fisica generale di sé. Inoltre, la percezione di sé dei maschi è generalmente più alta delle femmine anche se questa non corrisponde a più elevate capacità fisiche o ad un maggior livello di attività fisica

    Gamma-Ray Burst observations by the high-energy charged particle detector on board the CSES-01 satellite between 2019 and 2021

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    In this paper we report the detection of five strong Gamma-Ray Bursts (GRBs) by the High-Energy Particle Detector (HEPD-01) mounted on board the China Seismo-Electromagnetic Satellite (CSES-01), operational since 2018 on a Sun-synchronous polar orbit at a ∼\sim 507 km altitude and 97∘^\circ inclination. HEPD-01 was designed to detect high-energy electrons in the energy range 3 - 100 MeV, protons in the range 30 - 300 MeV, and light nuclei in the range 30 - 300 MeV/n. Nonetheless, Monte Carlo simulations have shown HEPD-01 is sensitive to gamma-ray photons in the energy range 300 keV - 50 MeV, even if with a moderate effective area above ∼\sim 5 MeV. A dedicated time correlation analysis between GRBs reported in literature and signals from a set of HEPD-01 trigger configuration masks has confirmed the anticipated detector sensitivity to high-energy photons. A comparison between the simultaneous time profiles of HEPD-01 electron fluxes and photons from GRB190114C, GRB190305A, GRB190928A, GRB200826B and GRB211211A has shown a remarkable similarity, in spite of the different energy ranges. The high-energy response, with peak sensitivity at about 2 MeV, and moderate effective area of the detector in the actual flight configuration explain why these five GRBs, characterised by a fluence above ∼\sim 3 ×\times 10−5^{-5} erg cm−2^{-2} in the energy interval 300 keV - 50 MeV, have been detected.Comment: Accepted for publication in The Astrophysical Journal (ApJ

    Numerical analysis of the interaction between high-pressure resin spray and wood chips in a vapour stream

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    This article investigates the interaction between the resin spray and the wood chips in a vapour stream using a multi-phase multi-component computational fluid dynamics approach. The interaction between the spray and the chips is one of the main issues in the industrial process for manufacturing medium density fibre boards. Thus, the optimization of this process can lead to important benefits, such as the reduction in the emission of formaldehyde-based toxic chemicals, the reduction in energy consumption in the blending process and energy saving in the fibreboard drying process. First step of the study is the numerical analysis of the resin injector in order to extend the experimental measurements carried out with water to the resin spray. The effects of the injector’s geometrical features on the spray formation are highlighted under different injection pressure values and needle displacements. Afterwards, the results obtained in the analysis of the single injector are used for the complete simulation of multi-injector rail where the mixing of the resin spray and wood chips takes place. The influence of the main operating conditions, such as the vapour and the wood chip flow rates, on the resin distribution is addressed in order to optimize the resination process

    Trunk muscles activation during pole walking vs. walking performed at different speeds and grades

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    Given their functional role and importance, the activity of several trunk muscles was assessed (via surface electromyography—EMG) during Walking (W) and Pole Walking (PW) in 21 healthy adults. EMG data was collected from the external oblique (EO), the erector spinae longissimus (ES), the multifidus (MU), and the rectus abdominis (RA) while performing W and PW on a motorized treadmill at different speeds (60, 80, and 100% of the highest speed at which the participants still walked naturally; PTS60, PTS80 and PTS100, respectively) and grades (0 and 7%; GRADE0 and GRADE7, respectively). Stride length, EMG area under the curve (AUC), muscles activity duration (ACT), and percentage of coactivation (CO-ACT) of ES, MU and RA, were calculated from the averaged stride for each of the tested combinations. Compared to W, PW significantly increased the stride length, EOAUC, RAAUC and the activation time of all the investigated muscles, to different extents depending on treadmill speeds and grades. In addition, MUAUC was higher in PW than in W at GRADE0 only (all speeds, p < 0.01), while ESAUC during W and PW was similar at all the speeds and grades. These changes resulted in longer CO-ACT in PW than W, at GRADE0-PTS100 (p < 0.01) and GRADE7 (all speeds, p < 0.01). In conclusion, when compared to W, PW requires a greater engagement of the abdominal muscles and, in turn, a higher control of the trunk muscles. These two factors taken together may suggest an elevated spinal stability while walking with poles

    Local stability and kinematic variability in walking and pole walking at different speeds

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    This study investigated the kinematic variability and the local stability of walking and pole walking using two tri-axial accelerometers placed on the seventh cervical (C7) and the second sacral (S2) vertebrae of twenty-one adults. Each participant performed three 1-min trials of walking and pole walking on a motorized treadmill (60, 80, 100% of the preferred walk-to-run transition speed). Forty strides per trial were used to calculate, in all directions of C7 and S2, the median of the stride-to-stride median absolute deviation (medMAD) and the local divergence exponent (λ). Generalised estimating equations and pairwise contrasts revealed, during pole walking, a higher medMAD (all directions, most speeds, C7 level only), and a lower λ (all directions, all speeds, both C7 and S2 level). As speed increased, so did medMAD (all directions, both walking with or without poles), with higher values at C7 compared to S2 level. A similar effect was observed for λ in the vertical direction (walking and pole walking), and in the anterior-posterior direction (only pole walking). An increase in speed brought about a λ reduction in the medial-lateral direction (C7 level only), especially during walking. Finally, both medMAD and λ were higher at C7 than S2 level (all directions, both walking and pole walking) except for λ in the anterior-posterior direction, which resulted higher in walking (C7 level only). In conclusion, despite a higher kinematic variability, pole walking appears to be more locally stable than walking at any speed, especially at C7 level