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1.
Eur J Appl Physiol ; 123(3): 523-531, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36367571

RESUMEN

PURPOSE: Both muscle mass and physical activity are independent mechanisms that play a role in vascular remodeling, however, the direct impact of muscle mass on the structure and function of the vessels is not clear. The aim of the study was to determine the impact of muscle mass alteration on lower limbs arterial diameter, blood flow, shear rate and arterial stiffness. METHODS: Nine (33 ± 13 yrs) male individuals with a single-leg amputation were recruited. Vascular size (femoral artery diameter), hemodynamics (femoral artery blood flow and shear rate were measured at the level of the common femoral artery in both amputated (AL) and whole limbs (WL). Muscle mass of both limbs, including thigh for AL and thigh and leg for WL, was measured with a DXA system. RESULTS: AL muscle mass was reduced compared to the WL (3.2 ± 1.2 kg vs. 9.4 ± 2.1 kg; p = 0.001). Diameter of the femoral artery was reduced in the AL (0.5 ± 0.1 cm) in comparison to the WL (0.9 ± 0.2 cm, p = 0.001). However, femoral artery blood flow normalized for the muscle mass (AL = 81.5 ± 78.7ml min-1 kg-1,WL = 32.4 ± 18.3; p = 0.11), and blood shear rate (AL = 709.9 ± 371.4 s-1, WL = 526,9 ± 295,6; p = 0.374) were non different between limbs. A correlation was found only between muscle mass and femoral artery diameter (p = 0.003, R = 0.6561). CONCLUSION: The results of this study revealed that the massive muscle mass reduction caused by a leg amputation, but independent from the level of physical activity, is coupled by a dramatic arterial diameter decrease. Interestingly, hemodynamics and arterial stiffness do not seem to be impacted by these structural changes.


Asunto(s)
Amputados , Pierna , Humanos , Masculino , Pierna/fisiología , Remodelación Vascular , Arteria Femoral/fisiología , Músculos , Flujo Sanguíneo Regional/fisiología
2.
Int J Sports Med ; 44(8): 576-583, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37207661

RESUMEN

This study explored the performance of the Sitting Volleyball serve by investigating the causal factors associated with ball velocity. Thirty-seven athletes underwent anthropometry and strength assessment and performed ten successful maximal effort serves. Ball velocity was measured using a sports radar gun. The hip, shoulder, elbow and wrist angles at the instant of ball impact as well as the height of ball impact were estimated through two-dimensional motion analysis. The causal relationships between variables were described through a linear Structural Equation Model and a Directed Acyclic Graph. Results showed that a smaller hip angle determines a greater shoulder angle, which in turn causes a greater elbow angle. A more open elbow angle together with a greater vertical reach allowed for a greater height of ball impact. Finally, increased height of ball impact along with greater abdominal strength are beneficial for higher ball velocity. These results underlined that the Sitting Volleyball serve is a multifactorial stroke involving anthropometric, technical and strength factors and suggest that athletes should improve their abdominal strength and master the technique necessary to perform the serve with the shoulder and the elbow joints fully extended in order to produce the greatest possible impact on the ball.


Asunto(s)
Voleibol , Humanos , Sedestación , Hombro , Codo , Muñeca , Fenómenos Biomecánicos
3.
Nutr Metab Cardiovasc Dis ; 32(9): 2168-2176, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35850750

RESUMEN

BACKGROUND AND AIMS: In this cross-sectional study we investigate the association between handgrip strength (HGS) and muscle function of the lower limbs and the predictors of the appendicular lean mass index (ALMI) in older adults with obesity of both sexes. METHODS AND RESULTS: Eighty-four older (67 ± 5 years) men (N = 44) and women (N = 40) with obesity (body mass index (BMI) 33 ± 4 kg/m2) performed: the HGS, isokinetic knee extensors (KE) and flexors (KF) muscle strength and power and Short Physical Performance Battery (SPPB). The correlation between HGS and lower limbs muscle function was evaluated, and four multiple hierarchical linear models were built to assess the contribution of each ALMI predictor (i.e., HGS, BMI, SPPB, muscle strength and power). In men, HGS was weakly-to-moderately associated (p < 0.05) with KE, KF muscle function and physical performance. In women, HGS showed a weak association (p < 0.05) with KE muscle function. The significant predictors of ALMI were only the BMI in women, whereas in the group of men BMI, KE maximal strength and power better explain the variance in ALMI than HGS alone. CONCLUSION: Our results suggest that HGS should not be used alone as a marker of lower muscle nor physical function. Sex differences exist with the BMI that is a contributor of ALMI both in men and women. However, at least in the group of men, markers related to strength and power of the lower limbs can better describe variations in ALMI compared to HGS in this kind of population. CLINICAL TRIAL REGISTRATION: NA.


Asunto(s)
Fuerza de la Mano , Sarcopenia , Anciano , Estudios Transversales , Femenino , Humanos , Extremidad Inferior , Masculino , Fuerza Muscular , Músculo Esquelético , Obesidad , Caracteres Sexuales
4.
J Sports Sci ; 40(10): 1097-1109, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35262456

RESUMEN

This study aimed to identify how body dimensions interact with anteroposterior block distances to influence lower limb joint angles in the "set" position, how these angles relate to block clearance kinetic and kinematic parameters, and how these biomechanical parameters influence sprint start performance in sprinters of both sexes and of different ability levels. Seventy-eight sprinters performed six maximal-effort 10 m sprints. Joint angles in the "set" position were quantified through 2D video analysis, and the forces generated during block exit were measured by dynamometric starting blocks. Lower limb length was associated with the front block-starting line distance ([FB/SL], partial correlation [rPC] = 0.48) and was a significant predictor of FB/SL (R2 = 0.39). The FB/SL was associated with front hip angle (rPC = 0.38), which was consequently associated with numerous kinetic variables during block clearance (rPC from -0.41 to -0.61). Coaches should be encouraged to explore the interactions between individual lower limb lengths and the FB/SL distance in both male and female sprinters to manipulate the front hip angle in the "set" position in an attempt to achieve more favourable block clearance kinetics.


Asunto(s)
Rendimiento Atlético , Carrera , Aceleración , Fenómenos Biomecánicos , Femenino , Humanos , Cinética , Masculino
5.
Int J Obes (Lond) ; 45(4): 895-905, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33526852

RESUMEN

BACKGROUND/OBJECTIVES: Muscle function is a marker of current and prospective health/independence throughout life. The effects of sex and obesity (OB) on the loss of muscle function in ageing remain unresolved, with important implications for the diagnosis/monitoring of sarcopenia. To characterise in vivo knee extensors' function, we compared muscles torque and power with isometric and isokinetic tests in older men (M) and women (W), with normal range (NW) of body mass index (BMI) and OB. SUBJECTS/METHODS: In 70 sedentary older M and W (69 ± 5 years), NW and OB (i.e. BMI < 30 kg m-2 and ≥30 kg m-2, respectively) we tested the right knee's extensor: (i) isometric torque at 30°, 60°, 75° and 90° knee angles, and (ii) isokinetic concentric torque at 60, 90, 150, 180 and 210° s-1 angular speeds. Maximal isometric T-angle, maximal isokinetic knee-extensor torque-velocity, theoretical maximal shortening velocity, maximal power, optimal torque and velocity were determined in absolute units, normalised by body mass (BM) and right leg lean mass (LLMR) and compared over sex, BMI categories and angle or angular speeds by three-way ANOVA. RESULTS: In absolute units, relative to BM and LLMR, sex differences were found in favour of M for all parameters of muscle function (main effect for sex, p < 0.05). OB did not affect either absolute or relative to LLMR isometric and isokinetic muscle function (main effect for BMI, p > 0.05); however, muscle function indices, when adjusted for BM, were lower in both M and W with OB compared to NW counterparts (p < 0.05). CONCLUSIONS: We confirmed sex differences in absolute, relative to BM and LLMR muscle function in favour of men. While overall muscle function and muscle contractile quality is conserved in individuals with class I OB, muscle function normalised for BM, which defines the ability to perform independently and safely the activities of daily living, is impaired in comparison with physiological ageing.


Asunto(s)
Envejecimiento , Rodilla/fisiología , Músculo Esquelético/fisiología , Obesidad , Factores Sexuales , Anciano , Anciano de 80 o más Años , Antropometría , Composición Corporal , Femenino , Humanos , Italia , Pierna , Masculino , Contracción Muscular , Fuerza Muscular , Conducta Sedentaria , Torque
6.
Int J Med Sci ; 17(7): 881-891, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32308541

RESUMEN

Measurement of body circumferences (BCs) is widely used as an anthropometric tool to assess body composition and health risk in obese individuals. In this preliminary work we evaluated the association of several BCs with Dual-energy X-ray Absorptiometry (DXA)-measured lean mass as well as leg press test scores with an aim at exploring the potential of BCs as predictor of body composition and muscle strength. A total of 34 female participants aged 47.3±7.6 y who were obese (BMI, 30.4-43.7 kg/m2) were recruited. The upper arm (relaxed), wrist, chest, waist, hip, thigh, and calf circumferences were measured. The skinfold-corrected muscle (including bone) circumferences at the arm, thigh, and calf site were also calculated. Lean mass components were measured by DXA with a Hologic QDR Explorer scanner according to the manufacturer's procedures. Lower limbs strength was assessed with the 1-Repetition Maximum leg press. Bivariate association between variables was assessed with the Spearman's correlation coefficient after the Benjamini and Hochberg False Discovery Rate procedure. Predictive equations were developed using stepwise multiple regression analysis. Several statistically significant correlations (Benjamini and Hochberg corrected P [Pc] < 0.05) were present between BCs and DXA-measured body composition variables, and leg press test scores with special regard to the chest, arm, waist, and hip circumferences. Multiple regression analysis yielded statistically significant predictive models (Pc < 0.05 for all; adjusted R2 ranging 0.123 - 0.504; standard error of the estimate ranging 4.0% - 11% of the mean measured value) for all body composition as well as leg press outcomes. The current findings show that BCs represent a simple, suitable anthropometric measurement with a potential to predict several lean mass components as well as lower limbs strength in obese females. The proposed predictors need to be validated in a larger sample of participants and in obese males.


Asunto(s)
Composición Corporal/fisiología , Fuerza Muscular/fisiología , Obesidad/fisiopatología , Absorciometría de Fotón , Adulto , Índice de Masa Corporal , Femenino , Humanos , Pierna/fisiología , Persona de Mediana Edad , Músculo Esquelético/fisiología , Músculo Esquelético/fisiopatología , Circunferencia de la Cintura/fisiología
7.
Aging Clin Exp Res ; 32(2): 207-214, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31535334

RESUMEN

BACKGROUND: Alterations in bone and muscle parameters related to advanced aging and physical inactivity have never been investigated in oldest-old women. AIMS: To investigate the impact of physical inactivity on bone mineral density (BMD) and body composition at the systemic and regional levels in oldest-old (> 75 years old) women. We hypothesized that, further to aging, alterations in bone and body composition parameters are exacerbated in the locomotor limbs that have experienced physical inactivity. METHODS: Whole-body and regional (lower limbs and trunk) BMD and fat-free soft tissue mass (FFSTM) were measured by means of dual-energy X-ray absorptiometry in 11 oldest-old wheelchair-bound women (OIW), 11 oldest-old mobile women (OMW), and 11 young healthy women (YW), all matched for weight (± 10 kg), height (± 10 cm). RESULTS: Whole-body BMD was reduced by 15% from YW to OMW and 10% from OMW to OIW. Whole-body FFSTM was also reduced from YW to OIW (- 13%). Lower limb BMD was progressively reduced among YW, OMW and OIW (- 23%). Similarly, lower limb FFSTM was reduced among YW (12,816 ± 1797 g), OMW (11,999 ± 1512 g) and OIW (10,037 ± 1489 g). Trunk BMD was progressively reduced among YW, OMW and OIW (- 19%), while FFSTM was similar among the three groups ~ 19801 g. CONCLUSIONS: The results of the present study suggest that the alterations in bone and body composition parameters are exacerbated in the physical inactive oldest-old. These negative effects of physical inactivity are not confined to the locomotor limbs, and a systemic decline of bone and muscle parameters are likely associated with the physical inactivity.


Asunto(s)
Huesos/fisiopatología , Músculo Esquelético/fisiopatología , Conducta Sedentaria , Absorciometría de Fotón , Adulto , Anciano , Anciano de 80 o más Años , Composición Corporal , Peso Corporal , Densidad Ósea , Femenino , Humanos
9.
J Sports Sci ; 35(5): 476-483, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27070868

RESUMEN

Improving motor skills represents one of the major issues in motor control and motor learning literature. The aim of this study was to investigate which of two strategies, method of amplification of error (MAE) or direct instruction (DI), would be more beneficial for error correction of the snatch technique. Thirty well-trained male weightlifters were randomly assigned to one of three training conditions (MAE, DI and Control). The experiment took place in only one practice session in which each lifter performed 3 pretraining trials, 8 training intervention trials, and 3 post-training trials, and a retention test session after 1 week. An optoelectronic motion capture system was used to measure the kinematic parameters of the weightlifting performance. After the training intervention, data showed that the MAE group revealed a greater improvement in several kinematic parameters when compared to the DI and Control groups, and the benefits derived from its application were still present 1 week later in the retention test. Nevertheless, the findings of the present study should be interpreted with caution due to the relatively small sample size; further research will also be necessary to evaluate the effects of MAE with different ability levels and other sport skills. The present findings could have practical implications for sport psychology and physical education because while practice is obviously necessary for improving learning, the efficacy of the learning process is essential in enhancing learners' motivation and sport enjoyment.


Asunto(s)
Retroalimentación Formativa , Destreza Motora/fisiología , Entrenamiento de Fuerza/métodos , Levantamiento de Peso/fisiología , Fenómenos Biomecánicos , Humanos , Masculino , Adulto Joven
10.
J Sports Sci ; 33(12): 1219-28, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25773172

RESUMEN

This work investigated changes in body composition of professional soccer players attending an Italian Serie A club across the competitive season; it is original insofar as body composition was assessed at multiple time points across the season using the accurate three-compartment model provided by Dual-Energy X-Ray Absorptiometry (DXA). Thirty-one players (4 goalkeepers, 13 defenders, 8 midfielders, 6 forwards) underwent DXA and anthropometry at pre-, mid- and end-season. One operator measured whole body and regional body composition (fat mass, FM; fat-free soft tissue mass, FFSTM; mineral mass). Two players were excluded from analysis due to serious injury. Data were analysed with repeated measures ANOVA; factors were season time point and playing position. Results showed that whole-body FM and %FM significantly (P < 0.001) decrease at mid-season (-11.9%; -1.3%, respectively) and end-season (-8.3%; -0.8%, respectively) whereas FFSTM significantly (P < 0.001) increase at mid-season (+1.3%) and end-season (+1.5%). Limited, but significant changes took place in bone mineral content. Some regional (upper and lower limbs, trunk) differences in the pattern of body composition changes across the season were also found. Changes were similar for all playing positions. It was concluded that professional soccer players undergo changes in their FM, FFSTM, and mineral mass across the season with some regional variations, irrespective of the playing position. Changes are mostly positive at mid-season, possibly due to difference in training between the first and second phase of the season.


Asunto(s)
Composición Corporal , Fútbol/fisiología , Absorciometría de Fotón , Adulto , Distribución de la Grasa Corporal , Índice de Masa Corporal , Densidad Ósea , Conducta Competitiva/fisiología , Humanos , Masculino , Factores de Tiempo , Adulto Joven
11.
PLoS One ; 19(5): e0302596, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38748742

RESUMEN

This study was designed to support the tactical decisions of wheelchair basketball (WB) coaches in identifying the best players to form winning lineups. Data related to a complete regular season of a top-level WB Championship were examined. By analyzing game-related statistics from the first round, two clusters were identified that accounted for approximately 35% of the total variance. Cluster 1 was composed of low-performing athletes, while Cluster 2 was composed of high-performing athletes. Based on data related to the second round of the Championship, we conducted a two-fold evaluation of the clusters identified in the first round with the team's net performance as the outcome variable. The results showed that teams where players belonging to Cluster 2 had played more time during the second round of the championship were also those with the better team performance (R-squared = 0.48, p = 0.035), while increasing the playing time for players from Classes III and IV does not necessarily improve team performance (r2 = -0.14, p = 0.59). These results of the present study suggest that a collaborative approach between coaches and data scientists would significantly advance this Paralympic sport.


Asunto(s)
Rendimiento Atlético , Baloncesto , Tutoría , Silla de Ruedas , Humanos , Tutoría/métodos , Masculino , Adulto
12.
Arch Gerontol Geriatr ; 127: 105559, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-39018967

RESUMEN

BACKGROUND: Aging is characterized by a physiological decline in physical function, muscle mass, strength, and power. Home-based resistance training interventions have gained increasing attention from scientists and healthcare system operators, but their efficacy is yet to be fully determined. AIMS: to verify the safety, feasibility, and efficacy of a home-based resistance training program delivered by innovative technological solution in healthy older adults. METHODS: 73 participants (36 females) were randomly allocated to either a control (C) or an intervention (I) group consisting of a 6-months home-based resistance training program delivered through an innovative technological solution, which included a wearable inertial sensor and a dedicated tablet. The safety and feasibility of the intervention were assessed by recording training-related adverse events and training adherence. Body composition, standing static balance, 10-meter walking, and loaded 5 sit-to-stand tests were monitored to quantify efficacy. RESULTS: No adverse events were recorded. Adherence to the training program was relatively high (61 % of participants performed the target 3 sessions) in the first trimester, significantly dropping during the second one. The intervention positively affected walking parameters (p < 0.05) and maximal force (p = 0.009) while no effect was recorded on body composition, balance, and muscle power. CONCLUSIONS: The home-based device-supported intervention was safe and feasible, positively affecting walking parameters and lower limbs' maximal force. This approach should be incentivized when barriers to participation in traditional resistance exercise programs are present.

13.
Acta Physiol (Oxf) ; 240(4): e14118, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38385696

RESUMEN

AIM: Force expression is characterized by an interplay of biological and molecular determinants that are expected to differentiate males and females in terms of maximal performance. These include muscle characteristics (muscle size, fiber type, contractility), neuromuscular regulation (central and peripheral factors of force expression), and individual genetic factors (miRNAs and gene/protein expression). This research aims to comprehensively assess these physiological variables and their role as determinants of maximal force difference between sexes. METHODS: Experimental evaluations include neuromuscular components of isometric contraction, intrinsic muscle characteristics (proteins and fiber type), and some biomarkers associated with muscle function (circulating miRNAs and gut microbiome) in 12 young and healthy males and 12 females. RESULTS: Male strength superiority appears to stem primarily from muscle size while muscle fiber-type distribution plays a crucial role in contractile properties. Moderate-to-strong pooled correlations between these muscle parameters were established with specific circulating miRNAs, as well as muscle and plasma proteins. CONCLUSION: Muscle size is crucial in explaining the differences in maximal voluntary isometric force generation between males and females with similar fiber type distribution. Potential physiological mechanisms are seen from associations between maximal force, skeletal muscle contractile properties, and biological markers.


Asunto(s)
MicroARNs , Caracteres Sexuales , Masculino , Humanos , Femenino , Contracción Muscular/fisiología , Músculo Esquelético/fisiología , Fibras Musculares Esqueléticas , Contracción Isométrica/fisiología , Electromiografía
14.
J Sports Med Phys Fitness ; 63(4): 558-565, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36305877

RESUMEN

BACKGROUND: In karate, high percentages of fat mass (%FM) are often associated with poor sport performance. Dual-energy X-ray absorptiometry (DXA) can accurately measure the %FM (%FM-DXA), but it may not be practical in some sport settings, where anthropometry has long been used as an alternative. This study aimed to explore the ability of sixteen available anthropometric equations to estimate the %FM (%FM-AE) in karate athletes using the %FM-DXA as the criterion. Furthermore, two population-specific predictive equations to estimate the %FM-DXA were developed from anthropometric measurements. METHODS: Forty-six male athletes aged 21.7±3.8 years underwent anthropometry and a whole-body DXA scan. RESULTS: The results showed that in male karate athletes all the considered anthropometric equations are mostly inaccurate in estimating the %FM-DXA within a range of the limits of agreement in the Bland-Altman analysis, which ranged from 6.43% to 13.37%. Regression analysis yielded two statistically significant models (P<0.001 for both) to predict the %FM-DXA. In the first model (cross-validated estimation of R2=0.85), the predictors were the abdominal, triceps, calf, and biceps skinfolds and in the second model (cross-validated estimation of R2=0.77), the predictor was the sum of nine skinfolds (i.e., biceps, triceps, subscapular, chest, axilla, suprailiac, abdominal, anterior thigh and calf skinfolds). CONCLUSIONS: These results underlined the need for sport-specific anthropometric equations to accurately estimate the %FM-DXA in male karate athletes. The two predictive anthropometric equations presented in this study provided a promising tool for professionals dealing with body composition in this athletic population to accurately estimate the %FM-DXA by means of anthropometry.


Asunto(s)
Composición Corporal , Artes Marciales , Humanos , Masculino , Absorciometría de Fotón/métodos , Antropometría/métodos , Atletas , Tejido Adiposo , Grosor de los Pliegues Cutáneos
15.
Eur J Sport Sci ; 23(7): 1110-1120, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36453590

RESUMEN

ABSTRACTFew studies have focused on the effect of individual anthropometrics when considering "set" position posture during the sprint start. This study aimed to measure the effect of different anthropometry-driven block settings on kinetic and kinematic parameters and performance during the start in well-trained and non-trained sprinters. Front block-starting line (FB/SL) distance was manipulated between 50% and 70% of each individual's leg length at 5% intervals, whilst the inter-block distance was held constant at 45% of leg length. Thirty-six sprinters performed three maximal-effort 10 m sprints in each of the five conditions. Joint angles in the "set" position were quantified though 2D video analysis, the forces generated during block clearance phase were measured by dynamometric starting blocks, and times to 5 and 10 m were measured with photocells. The effects of the five block setting conditions were largely consistent irrespective of ability level. Shorter FB/SL distances were associated with significantly more flexed hip and knee angles in the "set" position, a significantly more plantar flexed front ankle, and a significantly more dorsiflexed rear ankle. There were no significant effects of FB/SL distance on total block time, and thus the greater rear block peak forces and impulses produced from the shorter FB/SL distances combined with no effects on the resultant front block peak forces and impulses, led to higher levels of sprint start performance from the shorter FB/SL distances. Considering FB/SL distances closer to 50% of leg length may be beneficial for coaches and athletes to explore during sprint start training.HighlightsThe effects of different front-block starting line distances on "set" position kinematics, block clearance kinetics and sprint start performance are largely consistent irrespective of ability level.When using a medium inter-block distance (45% of leg length), shorter front block-starting line distances (down to 50% of the leg length) led to improved sprint start performance.From shorter front block-starting line distances, sprint start performance was primarily improved through greater force production against the rear block which led to greater impulses due to no change in push durations or resultant front foot forces.Lower-limb length is an important consideration when adjusting anteroposterior block distances.


Asunto(s)
Rendimiento Atlético , Carrera , Humanos , Aceleración , Articulación de la Rodilla , Fenómenos Biomecánicos , Antropometría
16.
PeerJ ; 11: e15785, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37719122

RESUMEN

Background: Information about non-elite wheelchair basketball (WB) players across national competitive seasons are still missing. This study aimed at identifying which situational-related variables were associated with shooting effectiveness in non-elite WB players. Methods: All the matches played by one WB team across one national competitive season were video-recorded and analysed; 333 shooting attempts from high-point players and several situational-related variables were considered. Results: Pearson's Chi-square test showed that increased shooting effectiveness under the following conditions: playing on home ground, during won matches, while taking shots with the wheelchair in motion, and when no opposing player raised their arm in defence. Results of the multivariable logistic regression analysis showed a statistically significant influence of match location (p-value = 0.001), shot-clock remaining (p-value = 0.015) and modality of press (p-value < 0.001). The highest attack effectiveness was achieved when teams played at home (odds ratio [OR] = 2.49), while the shooting effectiveness decreased when the shot occurred during the last seconds of the action (OR = 0.36), or the opponents defended with the arm raised (OR = 0.19). These results suggest that coaches should include exercises aimed at shooting under conditions of increased pressure in their programmes in order to create specific situations during the training sessions to prepare their high-point athletes for shots under specific match constraints.


Asunto(s)
Baloncesto , Silla de Ruedas , Humanos , Objetivos , Estaciones del Año , Atletas
17.
Biomedicines ; 11(1)2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36672627

RESUMEN

Type 2 diabetes (T2D) is a multisystem disease that is the subject of many studies, but the earliest cause of the disease has yet to be elucidated. Mitochondrial impairment has been associated with diabetes in several tissues. To extend the association between T2D and mitochondrial impairment to blood cells, we investigated T2D-related changes in peripheral mononucleated blood cells' (PBMCs) mitochondrial function in two groups of women (CTRL vs. T2D; mean age: 54.1 ± 3.8 vs. 60.9 ± 4.8; mean BMI 25.6 ± 5.2 vs. 30.0 ± 5), together with a panel of blood biomarkers, anthropometric measurements and physiological parameters (VO2max and strength tests). Dual-energy X-ray absorptiometry (DXA) scan analysis, cardio-pulmonary exercise test and blood biomarkers confirmed hallmarks of diabetes in the T2D group. Mitochondrial function assays performed with high resolution respirometry highlighted a significant reduction of mitochondrial respiration in the ADP-stimulated state (OXPHOS; −30%, p = 0.006) and maximal non-coupled respiration (ET; −30%, p = 0.004) in PBMCs samples from the T2D group. The total glutathione antioxidant pool (GSHt) was significantly reduced (−38%: p = 0.04) in plasma samples from the T2D group. The fraction of glycated hemoglobin (Hb1Ac) was positively associated with markers of inflammation (C-reactive protein-CRP r = 0.618; p = 0.006) and of dyslipidemia (triglycerides-TG r = 0.815; p < 0.0001). The same marker (Hb1Ac) was negatively associated with mitochondrial activity levels (OXPHOS r = −0.502; p = 0.034; ET r = −0.529; p = 0.024). The results obtained in overweight postmenopausal women from analysis of PBMCs mitochondrial respiration and their association with anthropometric and physiological parameters indicate that PBMC could represent a reliable model for studying T2D-related metabolic impairment and could be useful for testing the effectiveness of interventions targeting mitochondria.

18.
BMJ Open ; 13(12): e072291, 2023 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-38135320

RESUMEN

OBJECTIVE: Protein-energy malnutrition and the subsequent muscle wasting (sarcopenia) are common ageing complications. It is knowing to be also associated with dementia. Our programme will test the cytoprotective functions of vitamin E combined with the cortisol-lowering effect of chocolate polyphenols (PP), in combination with muscle anabolic effect of adequate dietary protein intake and physical exercise to prevent the age-dependent decline of muscle mass and its key underpinning mechanisms including mitochondrial function, and nutrient metabolism in muscle in the elderly. METHODS AND ANALYSIS: In 2020, a 6-month double-blind randomised controlled trial in 75 predementia older people was launched to prevent muscle mass loss, in respond to the 'Joint Programming Initiative A healthy diet for a healthy life'. In the run-in phase, participants will be stabilised on a protein-rich diet (0.9-1.0 g protein/kg ideal body weight/day) and physical exercise programme (high-intensity interval training specifically developed for these subjects). Subsequently, they will be randomised into three groups (1:1:1). The study arms will have a similar isocaloric diet and follow a similar physical exercise programme. Control group (n=25) will maintain the baseline diet; intervention groups will consume either 30 g/day of dark chocolate containing 500 mg total PP (corresponding to 60 mg epicatechin) and 100 mg vitamin E (as RRR-alpha-tocopherol) (n=25); or the high polyphenol chocolate without additional vitamin E (n=25). Muscle mass will be the primary endpoint. Other outcomes are neurocognitive status and previously identified biomolecular indices of frailty in predementia patients. Muscle biopsies will be collected to assess myocyte contraction and mitochondrial metabolism. Blood and plasma samples will be analysed for laboratory endpoints including nutrition metabolism and omics. ETHICS AND DISSEMINATION: All the ethical and regulatory approvals have been obtained by the ethical committees of the Azienda Ospedaliera Universitaria Integrata of Verona with respect to scientific content and compliance with applicable research and human subjects' regulation. Given the broader interest of the society toward undernutrition in the elderly, we identify four main target audiences for our research activity: national and local health systems, both internal and external to the project; targeted population (the elderly); general public; and academia. These activities include scientific workshops, public health awareness campaigns, project dedicated website and publication is scientific peer-review journals. TRIAL REGISTRATION NUMBER: NCT05343611.


Asunto(s)
Chocolate , Desnutrición Proteico-Calórica , Anciano , Humanos , Proteínas en la Dieta , Vitamina E/uso terapéutico , Ejercicio Físico , Ensayos Clínicos Controlados Aleatorios como Asunto
19.
Front Physiol ; 13: 934622, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36338502

RESUMEN

There is lack of information about bone mineralization at the lumbar spine and bilateral hips of athletes with unilateral lower limb amputation. The present study assessed for the first time the areal bone mineral density at the lumbar spine and at the hip of the able and impaired leg by means of Dual-Energy X-Ray Absorptiometry using a large sample (N = 40) of male athletes. Results showed that bone demineralization in athletes with unilateral lower limb amputation is found at the impaired hip but not at the lumbar spine and may therefore be site-specific. The extent of hip demineralization was influenced by the level of amputation, with about 80% of athletes with above knee amputation and 10% of athletes with below knee amputation showing areal bone mineral density below the expected range for age. Nevertheless, a reduced percentage of fat mass and a lower fat-to-lean mass ratio in the residual impaired leg as well as a greater amount of weekly training was positively associated with bone mineralization at the impaired hip (partial correlation coefficients = 0.377-0.525, p = 0.040-0.003). Results showed that participation in adapted sport has a positive effect on bone health in athletes with unilateral lower limb amputation but is not sufficient to maintain adequate levels of bone mineralization at the impaired hip in athletes with above-knee amputation. Accordingly, physical conditioners should consider implementing sporting programs, according to the severity of the impairment, aimed at improving bone mineralization at the impaired hip and improve body composition in the residual impaired leg.

20.
Children (Basel) ; 9(3)2022 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-35327763

RESUMEN

Recreational dance is practiced worldwide as a multidimensional physical activity with a potential for prevention of a sedentary lifestyle and overweight/obesity. This study explored in young (7−15 year; n = 21) girls the effect of long-term (>1 year) exposure to recreational (2 h/w) dancing on three-compartment body composition. Recreational dancers (RD) were compared with recreational (≤4 h/w) artistic gymnasts (RG, n = 22) and physically active young girls not involved in structured extracurricular physical activity (control; C, n = 22), adjusting for confounding variables (age, body mass, menarche). We hypothesized for RD an intermediate body composition between RG and C. The three groups had similar age and body mass index. Body composition indices in RD were intermediate between that of C and RG, but RD values were not statistically significantly different vs. C. This agreed with the not statistically significant higher energy expenditure (MET-min/w) in RD vs. C (1357.7 ± 805.32 and 1090.9 ± 596.63, p = 0.172). In conclusion, long-term recreational dance exposure at low volume had limited positive effect on body composition of young girls vs. unstructured extracurricular physical activity. Future work will explore the potential of recreational dance at higher volume (3−4 h/w) to improve body composition in young girls.

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