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1.
Sports (Basel) ; 12(3)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38535726

RESUMO

This study investigated the impact of basketball-induced fatigue on 3-point jump shooting accuracy, the ball's entry angle (EA) into the hoop, shot release time (RT), their relationship with player positions in high-level basketball, and the correlation between cardiorespiratory fitness markers and potential shooting performance changes. Guards (n = 13), forwards (n = 13), and centers (n = 12) underwent physiological assessments. Sequentially, they performed 15 jump shots (PRE), a basketball exercise simulation (BEST) involving 24 × 30 s circuit activities, and a repeated shooting test (POST). The study design was double-blind. The results revealed significant differences (p ≤ 0.05) in RT, EA, and successful shots (SSs) between PRE and POST in each group. The percentage changes from PRE to POST conditions across guards, forwards, and centers were for RT: 25.34% [95%CI: 1.7-48.98], 19.73% [95%CI: -1.9-41.36], 14.95% [95%CI: -5.23-35.13]; for EA: -3.89% [95%CI: -14.82-7.04], -3.13% [95%CI: -12.9-6.64], -3.47% [95%CI: -14.19-7.25]; and for SS: -14.42% [95%CI: -36.5-7.66], -16.76% [95%CI: -40.81-7.29], -19.44% [95%CI: -46.7-7.82], respectively. Post-test differences (p ≤ 0.05) highlighted greater fatigue impact on RT, EA, and SS from guards to centers. Additionally, significant correlations (p ≤ 0.05) were found between the ventilatory threshold, mean HR during BEST, and changes in RT, EA, and SS. This study highlights the substantial impact of basketball-induced fatigue on 3-point shooting parameters across player positions and the interplay with cardiorespiratory factors post-fatigue. Tailored training, considering heart rate, is crucial to optimizing shooting performance.

2.
Nutrients ; 16(1)2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38201999

RESUMO

Pre-exercise mangiferin-quercetin may enhance athletic performance. This study investigated the effect of mangiferin-quercetin supplementation on high-level male basketball players during a basketball exercise simulation test (BEST) comprising 24 circuits of 30 s activities with various movement distances. The participants were divided into two groups (EXP = 19 and CON = 19) and given a placebo one hour before the BEST (PRE-condition). The following week, the EXP group received mangiferin-quercetin (84 mg/140 mg), while the CON group received a placebo (POST-condition) before the BEST in a double-blind, cross-over design. The mean heart rate (HR) and circuit and sprint times (CT and ST) during the BEST were measured, along with the capillary blood lactate levels (La-), the subjective rating of muscle soreness (RPMS), and the perceived exertion (RPE) during a resting state prior to and following the BEST. The results showed significant interactions for the mean CT (p = 0.013) and RPE (p = 0.004); a marginal interaction for La- (p = 0.054); and non-significant interactions for the mean HR, mean ST, and RPMS. Moreover, the EXP group had significantly lower values in the POST condition for the mean CT (18.17 ± 2.08 s) and RPE (12.42 ± 1.02) compared to the PRE condition (20.33 ± 1.96 s and 13.47 ± 1.22, respectively) and the POST condition of the CON group (20.31 ± 2.10 s and 13.32 ± 1.16, respectively) (p < 0.05). These findings highlight the potential of pre-game mangiferin-quercetin supplementation to enhance intermittent high-intensity efforts in sports such as basketball.


Assuntos
Basquetebol , Xantonas , Humanos , Masculino , Estudos Cross-Over , Suplementos Nutricionais , Quercetina , Método Duplo-Cego
3.
Respir Physiol Neurobiol ; 319: 104168, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37797907

RESUMO

This study examined the effect of breath-hold (BH) training on apnoeic performance in novice BH divers (NBH:n = 10) and compared them with data from elite BH divers (EBH:n = 11). Both groups performed 5-maximal BHs (PRE). The NBH group repeated this protocol after two weeks of BH training (POST). The NBH group during BH efforts significantly increased red blood cell concentration (4.56 ± 0.16Mio/µl) by 5.06%, hemoglobin oxygen saturation steady state duration (110.32 ± 29.84 s) by 15.48%, and breath-hold time (BHT:144.19 ± 47.35 s) by 33.77%, primarily due to a 59.70% increase in struggle phase (71.85 ± 30.89 s), in POST. EBH group exhibited longer BHT (283.95 ± 36.93 s) and struggle-phase (150.10 ± 34.69 s) than NBH (POST). Elite divers recorded a higher peak MAP (153.18 ± 12.28 mmHg) compared to novices (PRE:123.70 ± 15.65 mmHg, POST:128.30 ± 19.16 mmHg), suggesting that a higher peak MAP is associated with a better BHT. The concurrent abrupt increase of diaphragmatic activity and MAP, seen only in the EBH group, suggests a potential interaction. Additionally, apnoea training increases red blood cells concentration in repeated apnoea efforts and increases BH stamina.


Assuntos
Apneia , Mergulho , Humanos , Apneia/complicações , Mergulho/fisiologia , Suspensão da Respiração , Diafragma
4.
J Sports Sci Med ; 22(4): 645-657, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38045735

RESUMO

Soccer is a complex sport, and balance appears to play a crucial role in the quality execution of technical skills, which are mostly performed while standing on one foot. Nevertheless, in younger ages, when learning still affects soccer performance, the effect of a balance-training program on the player's balance and technical skills remains unexplored. This research examined the effect of a balance-training program (BTP) on balance and technical skills of adolescent soccer players. Τhe participating volunteers were thirty-two soccer players (12-13 years old with 3.84 ± 0.95 years of practice), randomly separated into two groups: an experimental (EXP, n1 = 17) and a control group (CON, n2 = 15). Both groups were evaluated in static and dynamic balance and in technical skills (dribbling, passing, juggling, and shooting with dominant and non-dominant legs) before (Pre-condition) and after the intervention (Post-condition) which was an eight-week BTP for the EXP group and a placebo-training program for the CON group. Α 2 by 2 (groups×condition) mixed analysis of variance (ANOVA) with repeated measures on the condition factor was used to assess possible differences between groups. A significant groups × condition interaction effect was found in dynamic balance (p = 0.008), static (p = 0.042), and shooting (p = 0.022) with dominant leg performance. The EXP group improved (p = 0.007) its static balance by 37.82% and also significantly improved its dynamic balance and shooting accuracy with dominant leg in Post condition by 24.98% (p = 0.006) and 83.84% (p = 0.006) respectively. No significant improvement of other variables was detected in the EXP group Post condition. Dynamic and static balance, and shooting with dominant leg skills can be improved in adolescent soccer players through a specialized 8-week BTP. Balance-training program may contribute to technical skill improvement in soccer training.


Assuntos
Futebol , Humanos , Adolescente , Criança , Extremidade Inferior , Perna (Membro) , , Análise de Variância
5.
Data Brief ; 51: 109723, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37965614

RESUMO

This dataset was created with the primary objective of elucidating the intricate relationship between the incidence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) re-infections and the pre-illness vaccination profile and types concerning alterations in sports-related physical activity (PA) after SARS-CoV-2 infection among adults. A secondary objective encompassed a comprehensive statistical analysis to explore the influence of three key factors-namely, Vaccination profile, Vaccination types, and Incidence of SARS-CoV-2 re-infections-on changes in PA related to exercise and sports, recorded at two distinct time points: one to two weeks prior to infection and one month after the last SARS-CoV-2 infection. The sample population (n = 5829), drawn from Hellenic territory, adhered to self-inclusion and exclusion criteria. Data collection spanned from February to March 2023 (a two-month period), involving the utilization of the Active-Q (an online, interactive questionnaire) to automatically assess weekly habitual sports-related PA among adults both before and after their last SARS-CoV-2 infection. The questionnaire also captured participant characteristics, pre-illness vaccination statuses (i.e., unvaccinated, partially vaccinated, fully vaccinated, and vaccine types), and occurrences of SARS-CoV-2 re-infections. The dataset sheds light on two noteworthy phenomena: (i) the intricate interplay between post-acute SARS-CoV-2 infection and a decline in sports-related physical activity (-27.6 ± 0.6%, 95%CI: -26.1 - -29.1), influenced by the pre-illness vaccination profile factor (p = 0.040); and (ii) the divergence in sports-related physical activity decline between partially vaccinated (-38.2 ± 0.7%, 95%CI: -35.3 - -41.1, p = 0.031) and fully vaccinated respondents (-19.2 ± 0.5%, 95%CI: -17.2 - -21.2). These phenomena underscore the imperative for tailored interventions and further investigation to promote the resumption of physical activity and mitigate long-term repercussions. Furthermore, this dataset enriches our understanding of the dynamics of sports-related physical activity and provides valuable insights for public health initiatives aiming to address the consequences of COVID-19 on sports-related physical activity levels. Consequently, this cross-sectional dataset is amenable to a diverse array of analytical methodologies, including univariate and multivariate analyses, and holds potential relevance for researchers, leaders in the sports and medical sectors, and policymakers, all of whom share a vested interest in fostering initiatives directed at reinstating physical activity and mitigating the enduring ramifications of post-acute SARS-CoV-2 infection.

6.
Microbiol Spectr ; 11(6): e0217923, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37855460

RESUMO

IMPORTANCE: Nosocomiicoccus species are recently described as members of the Staphylococcaceae family. With their inclusion in commercial matrix-assisted laser desorption/ionization-time of flight mass spectrometry databases, Nosocomiicoccus species can now be identified when Gram-positive cocci in clusters are detected in positive blood cultures. However, their clinical significance is not known, making it difficult for the clinical microbiology laboratory to decide the extent of work-up. Based on our study, Nosocomiicoccus species demonstrate low pathogenicity and opportunistic potential. If isolated from a single blood culture set, limited work-up should be performed to an extent similar to other possible blood culture contaminants.


Assuntos
Bacteriemia , Hemocultura , Humanos , Relevância Clínica , Staphylococcaceae , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Bacteriemia/microbiologia
7.
Vaccines (Basel) ; 11(9)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37766108

RESUMO

This study investigated changes in physical activity (PA) after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection while considering age, PA level, underlying medical conditions (UMCs), vaccination profiles/types, re-infections, disease severity, and treatment. Data were collected from 5829 respondents by using a validated web-based questionnaire. The findings showed that there was a significant overall decrease in PA (-16.2%), including in daily occupation (-11.9%), transportation (-13.5%), leisure-time (-16.4%), and sporting (-27.6%) activities. Age, PA level, UMCs, vaccination profiles/types, disease severity, and treatment played a role in determining PA in individuals' post-acute SARS-CoV-2 infections. Re-infections did not impact the decline in PA. Unvaccinated individuals experienced a significant decline in PA (-13.7%). Younger (-22.4%) and older adults (-22.5%), those with higher PA levels (-20.6%), those with 2-5 UMCs (-23.1%), those who were vaccinated (-16.9%) or partially vaccinated (-19.1%), those with mRNA-type vaccines only (-17.1%), those with recurrent (-19.4%)-to-persistent (-54.2%) symptoms, and those that required hospital (-51.8%) or intensive care unit (-67.0%) admission during their infections had more pronounced declines in PA. These findings emphasize the complex relationship between post-acute SARS-CoV-2 infection and PA and highlight the need for targeted interventions, further research, and multidisciplinary care to promote PA resumption and mitigate long-term effects on global public health.

8.
Sports (Basel) ; 11(7)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37505614

RESUMO

BACKGROUND: Our aims were to investigate the time-course effects of a futsal match on performance, oxidative stress, and muscle damage markers, as well as inflammatory and antioxidant responses during a 6-day post-match period. METHODS: Thirty-four female high-level futsal players were assessed on several oxidative stress, inflammation, subjective muscle soreness, subjective rate perceived exertion, and performance tests before a futsal match, immediately after, and 24 h to 144 h after. RESULTS: Counter movement jump, 20 m, and 10 m sprints performance significantly decreased immediately after the match (p < 0.05) and returned to baseline 72 h post-match (p > 0.05). Delayed onset muscle soreness peaked 24 h post-match and rate perceived exertion peaked post-match (p < 0.05) and returned to baseline 96 h post-match (p > 0.05). Inflammatory biomarkers peaked at 24 h (p < 0.05) and remained significantly elevated for 72 h after the match (p < 0.05). Muscle damage biomarkers peaked at 24 h (p < 0.05) and remained significantly (p < 0.05) elevated for at least 72 h after the match. Oxidative stress markers peaked at 24 h-48 h (p < 0.05) and returned to baseline 120 h post-match (p > 0.05). In respect to antioxidant responses, these peaked at 24 h-48 h post-match (p < 0.05) and returned to baseline 120 h after the match (p > 0.05). CONCLUSIONS: A single futsal match induces short/mid-term changes in performance, inflammation, oxidative stress, and muscle damage markers for about 72 h-96 h post-match.

9.
Clin Infect Dis ; 76(3): e1071-e1078, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35675378

RESUMO

BACKGROUND: The incidence of Clostridioides difficile infection (CDI) has been rising among hospitalized children, with poor understanding of genomic variability of C. difficile isolates in this population. METHODS: This was a retrospective cohort study of CDI in inpatient and outpatient pediatric oncology and cell transplant patients (POTPs) in 2016 and 2017. CDI cases were identified by positive C. difficile toxin polymerase chain reaction tests. Retrieved residual stool specimens were cultured anaerobically and toxin-producing C. difficile isolates underwent whole genome sequencing (WGS) followed by core genome multilocus sequence typing. Plausible time and location epidemiologic links among the closely related strains were evaluated to identify potential transmission events. RESULTS: Among 226 CDI episodes in 157 patients, 202 stool samples were cultured and had positive cytotoxicity tests. Sequencing identified 33 different strain types in 162 (80%) isolates. Thirty-nine (28%) patients had multiple episodes of CDI, and 31 clusters of related isolates were identified, 15 (47%) of which involved exclusively multiple specimens from the same patient. For the 16 clusters involving multiple patients, epidemiologic investigation revealed only 2 (12.5%) clusters with potential transmission events. CONCLUSIONS: WGS identified a highly diverse group of C. difficile isolates among POTPs with CDI. Although WGS identified clusters of closely related isolates in multiple patients, epidemiologic investigation of shared inpatient exposures identified potential transmission in only 2 clusters. Clostridioides difficile transmission was uncommon in this population. More than 70% of new CDI reinfections in POTPs are actually recurrences caused by a previous CDI strain.


Assuntos
Clostridioides difficile , Infecções por Clostridium , Neoplasias , Criança , Humanos , Clostridioides difficile/genética , Clostridioides/genética , Epidemiologia Molecular , Estudos Retrospectivos , Sequenciamento Completo do Genoma , Infecções por Clostridium/epidemiologia
10.
J Funct Morphol Kinesiol ; 7(4)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36547662

RESUMO

Jumping ability in basketball is usually assessed using standardized vertical jump tests. However, they lack specificity and do not consider the player's basketball skills. Several studies have suggested performing specific jump tests, which are tailored to the movement patterns and requirements of a basketball game. The pivot step jump test (PSJT) is a novel test designed to evaluate the specific jumping abilities of basketball players by combining a pivot step on one leg with a maximum bilateral vertical jump. This study had two aims: to determine the reliability and validity of the PSJT using typical jump tests as the criterion measure and to demonstrate the PSJT as a practical test to evaluate specific jumping ability in young male and female basketball players. Twenty female (EGA; 14.0 ± 0.7 years, 59.3 ± 7.9 kg, 162.1 ± 5.5 cm) and fifteen male (EGB; 14.0 ± 0.7 years, 58.1 ± 7.7 kg, 170.3 ± 6.4 cm) basketball players participated in the study. The test−retest reliability of the PSJT within sessions (intrasession reliability) and across sessions (intersession reliability) was assessed within EGA. For the evaluation of validity, EGB performed the PSJT and a series of criterion jumping tests. For EGA, no changes (p > 0.05) were found in PSJT performance between test sessions and excellent intra- and intersession reliability was observed (ICCs > 0.75). Correlation coefficients indicated high factorial validity between the jumping tests and PSJT (r = 0.71−0.91, p < 0.001). The PSJT appears to offer a valid assessment of jumping ability in basketball and is a practical test for assessing sport-specific jumping skills in young basketball players.

11.
Sports (Basel) ; 10(7)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35878113

RESUMO

The purpose of this study was to examine the effect of a soccer small-sided game (SSG) on performance, inflammatory, muscle damage and hormonal indicators. Twenty-two male soccer players participated and were assigned to either experimental (EXP = 12) or control (CON = 10) groups. Subjective fatigue (RPE) and lactate (La¯) were measured during the SSG; vertical squat jump (SJ), 20-m sprint, creatine kinase (CK), interleukin-6 (IL-6), cortisol (C), and testosterone (T) were measured before (PRE), after (POST), 24 h, 48 h, and 72 h after the SSG in the EXP group. The heart rate during the SSG reached 92 ± 3% of their HRmax, whereas La¯ and RPE reached 13.02 ± 1.60 mmol·L−1 and 15 ± 1 after SSG, respectively. The IL-6, different among measurements (F (1.04, 11.50) = 504.82, p < 0.001), peaked (3.52 ± 0.43 pg·mL−1 [95%CI; 3.28−3.77]) after the SSG and returned to baseline 24 h later. The CK, different among measurements (F (1.76, 19.32) = 93.96, p < 0.001), peaked (536.58 ± 124.73U·L−1 [95%CI; 466.01−607.15]) 24 h after the SSG and remained significantly higher than PRE condition in POST and up to 72 h later. The T/C ratio, significantly different among measurements (F (1.73, 19.05) = 12.12, p < 0.001), was at its lowest (0.44 ± 0.16 [95%CI; 0.35−0.54]) immediately after the SSG (p < 0.05) and returned to baseline after 24 h. It seems that 48 h (at the most) after an SSG is adequate time for players to recover, and a high training load should be avoided sooner than 24 h after an SSG.

14.
Nutrients ; 13(12)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34959776

RESUMO

Carbohydrate (CHO) supplementation during prolonged exercise postpones fatigue. However, the optimum administration timing, dosage, type of CHO intake, and possible interaction of the ergogenic effect with athletes' cardiorespiratory fitness (CRF) are not clear. Ninety-six studies (from relevant databases based on predefined eligibility criteria) were selected for meta-analysis to investigate the acute effect of ≤20% CHO solutions on prolonged exercise performance. The between-subject standardized mean difference [SMD = ([mean post-value treatment group-mean post-value control group]/pooled variance)] was assessed. Overall, SMD [95% CI] of 0.43 [0.35, 0.51] was significant (p < 0.001). Subgroup analysis showed that SMD was reduced as the subjects' CRF level increased, with a 6-8% CHO solution composed of GL:FRU improving performance (exercise: 1-4 h); administration during the event led to a superior performance compared to administration before the exercise, with a 6-8% single-source CHO solution increasing performance in intermittent and 'stop and start' sports and an ~6% CHO solution appearing beneficial for 45-60 min exercises, but there were no significant differences between subjects' gender and age groups, varied CHO concentrations, doses, or types in the effect measurement. The evidence found was sound enough to support the hypothesis that CHO solutions, when ingested during endurance exercise, have ergogenic action and a possible crossover interaction with the subject's CRF.


Assuntos
Desempenho Atlético/fisiologia , Aptidão Cardiorrespiratória/fisiologia , Carboidratos da Dieta/administração & dosagem , Substâncias para Melhoria do Desempenho/administração & dosagem , Resistência Física/efeitos dos fármacos , Adulto , Feminino , Humanos , Masculino , Soluções , Fatores de Tempo
15.
MethodsX ; 8: 101490, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34754762

RESUMO

It was hypothesized that executing repeated maximum apnea efforts would improve performance in a subsequent time to exhaustion test. Indeed, in young moderately fit male subjects without former experience in apnea has been shown that five repeated apnea maximal efforts with face immersion in cold water (PEA) have advantageous effect to consecutive performance in a time to exhaustion ride without being further affected by apnea training of two weeks. So, in the current article, we describe, in details, the protocol procedure and the technical steps of the five maximum-repeated apnea maneuvers prior to a middle-distance racing in order to improve performance, from our previous relevant published research.

16.
Data Brief ; 39: 107480, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34664028

RESUMO

The impact of lockdown on life style and behaviour have piqued the interest of people and scientific community, all over the world. It has been demonstrated that in some countries, mandatory stay-at-home limitations and self-isolation measures are linked to an increase in sleeping hours and smoking cigarettes per day. However, these results derive from countries that lockdown had different features and length, and it is possible that society, culture, customs, ecological or other factors may independently or in combination affect life style habits (such sleeping and smoking) in different populations. So, we focus on sleeping and smoking changes in Greek adults during the lockdown of early COVID-19 presence in Greece. Therefore, our aim was to investigate whether lockdown alters smoking and sleeping habits and whether physical activity (PA), gender, age or body mass index (BMI) play a role. The modified online-based Active-Q (Greek version) questionnaire (see Supplementary file 1_Active-Q_modyfied) was used to collect data prior to the COVID-19 pandemic (PRE condition) and during physical distancing and lockdown measures (POST condition). The data period collection was from April 4 to April 19, 2020 (15 days in total) and respondents classified into four PA categories based on their sporting activities (PRE condition), five age categories and four BMI categories, which corresponding to different subgroup. Overall, sleeping hours change (from PRE to POST condition) was 11.80% and smoking cigarettes per day change was 9.35%. However, it appears that between the different subgroups significant differences were also identified.

17.
Sports (Basel) ; 9(6)2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34204988

RESUMO

Due to concerns regarding the spread of coronavirus (COVID-19), major sporting events and activities have been temporarily suspended or postponed, and a new radical sports protocol has emerged. For most sports there are few recommendations based on scientific evidence for returning to team-game activities following the lifting of COVID-19 restrictions, the extended duration of lockdown, and self-training or detraining in the COVID-19 environment, and this is especially true for basketball. A post-lockdown return to the basketball court ultimately depends on the teams-coaches, trainers, players, and medical staff. Nevertheless, our current scientific knowledge is evidently insufficient as far as safety and return-to-play timing are concerned. This situation presents a major challenge to basketball competition in terms of organization, prioritization, maintaining physical fitness, and decision-making. While preparing an adequate basketball return program, the players' health is the major priority. In this article we briefly discuss the topic and propose multiple strategies.

18.
Respir Physiol Neurobiol ; 292: 103703, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34087491

RESUMO

Ten subjects were tested on a cycle ergometer to exhaustion with intensity corresponding to 150 % of their peak power output (TF150) under three conditions [C: base line measurement; PRE: after five repeated breath hold maneuvers (BH); and POST: after 5BH, preceded by two weeks of BH training]. Respiratory and blood measurements were carried out. Upon cessation of 5BH, subjects compared to C condition started TF150 with reduced arterialized blood pH (C:7.428±0.023, PRE:7.419±0.016, POST:7.398±0.021) and elevated bicarbonate concentration (mmol/l), ventilation (l/min) and oxygen uptake (ml/min) (C:28.4±1.5, PRE:29.9±1.2, POST:30.0±1.8; C:10.4±2.5, PRE:13.3±3.3, POST:15.6±5.6; C:333.0±113.8, PRE:550.1±131.1, POST:585.1±192.8, respectively). After TF150, subjects had significantly reduced pH and elevated ventilation, and oxygen uptake in PRE and POST, in comparison to the C condition. TF150 (sec) significantly improved after 5BH without being further affected by BH training (C:44.8±8.1, PRE:49.2±4.8, POST:49.3±8.2). Priming breath holds prior to middle-distance racing may improve performance.


Assuntos
Apneia/metabolismo , Apneia/fisiopatologia , Desempenho Atlético/fisiologia , Exercício Físico/fisiologia , Esforço Físico/fisiologia , Acidose/sangue , Adulto , Ciclismo/fisiologia , Humanos , Hipercapnia/sangue , Masculino , Reprodutibilidade dos Testes , Fatores de Tempo , Adulto Jovem
19.
Res Q Exerc Sport ; 92(3): 537-548, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32657642

RESUMO

High intensity exercise can lead to depletion of CO2 from the body (hypocapnia). This disturbance becomes more noticeable during recovery or between seasons of intermittent exercise, putting the subject in a neural fatigue state. Objectives: A possible hypothesis to address this condition would be to provide high CO2 mixtures (hypercapnic) during the recovery period from exercise in order to relieve hypocapnia. Methods: Eight men (23.8 ± 1.2 yrs, VO2max = 45 ± 1.9 ml▪kg-1▪min-1) performed cycling exercise at 80%VO2max for 6-7 min. During recovery (23 min) they inhaled hypercapnic air (EXP-21%O2, 3%CO2, and 76%N2) or normal air (CON-21%O2, 0.003%CO2, and 79%N2). Respiratory parameters were collected with open spirometry and heart rate was measured. Results: Exercise caused mild hypocapnia {9.9 mmHg drop of CO2 end-expiratory partial pressure (PETCO2)} in CON condition after exercise (p < .005). PETCO2 elevated close to the rest values during the three hypercapnic phases in EXP condition (main effect of condition p < .001 between EXP and CON), but after hypercapnic breathing it returned to hypocapnia similarly with CON. The ventilatory response (VE▪PETCO2-1) and the exhaled volume of CO2 (VCO2) progressively increased during and also after ventilatory manipulations in EXP compared to CON condition (VE▪PETCO2-1: post hoc p < .001, VCO2: pVCO2: p < .05-.001), and VO2 became lower after the end of second hypercapnic manipulation (p < .05 between EXP and CON). Conclusion: It seems that hypercapnic breathing after exercise is not a good strategy to reverse exercise hypocapnia, because of great hyperventilation caused by CO2 and exercise mechanisms during the recovery period leading to increased CO2 removal from body. This intervention may also decrease O2 supply and muscles blood flow.


Assuntos
Administração por Inalação , Ciclismo/fisiologia , Dióxido de Carbono/administração & dosagem , Dióxido de Carbono/metabolismo , Exercício Físico/fisiologia , Adulto , Humanos , Masculino , Oxigênio/administração & dosagem , Adulto Jovem
20.
Sports (Basel) ; 8(10)2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33096721

RESUMO

It is well known that physical inactivity increases the risk of global death; however, the impact of the coronavirus disease 2019 (COVID-19) lockdown strategy on physical activity (PA) remains unclear. This study compared PA-i.e., daily occupation, transportation to and from daily occupation, leisure time activities, and regular sporting activities-prior (PRE) and during (POST) the on-going COVID-19 outbreak in the Greece lockdown environment. A Greek version of the web-based Active-Q questionnaire was used to access PA. The questionnaire was filled out twice (once each for the PRE and POST conditions) by 8495 participants (age = 37.2 ± 0.2 years (95% confidence interval (CI), 36.9-37.5); males = 38.3% (95%CI, 36.7-40.0); females = 61.7% (95%CI, 60.4-63.0). The relative frequency of overall sporting activities, which, prior to lockdown, occurred at least once per month, and overall participation in competitive sports was significantly reduced (8.6% (95%CI, 7.9-9.3) and 84.7% (95%CI, 82.9-86.6) respectively). With the exception of overall leisure time activities, which were significantly increased in the POST condition, daily occupational, transportation, and sporting activities significant reduced (p < 0.05). Overall PA was reduced in all genders, age, body mass index (BMI) and PA level subgroups in the POST condition, and an interaction between the males and High PA subgroups was observed. The change in overall PA (from PRE to POST conditions) was -16.3% (95%CI, -17.3 to -15.4), while in daily occupational, transportation, and sporting activities, it was -52.9% (95%CI, -54.8-51.0), -41.1% (95%CI, -42.8-39.5) and -23.9% (95%CI, -25.1-22.8), respectively. Thus, the lockdown period is highly associated with a negative change in overall PA. During lockdown, inactivity increased dramatically, with males and the high PA population affected significantly more. The decline in PA is a great concern due to possible long-term consequences on public health and healthcare system.

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