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1.
Medicina (Kaunas) ; 57(1)2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33435292

RESUMO

Background and objectives: The COVID-19 outbreak has become a major health and economic crisis. The World Health Organization declared it a pandemic in March 2020, and many sporting events were canceled. Materials and Methods: We examined the effects of the COVID-19 pandemic on endurance and ultra-endurance running (UER) and analyzed finishes and events during the COVID-19 pandemic (observation period March 2020-October 2020) to the same time period pre-COVID-19 outbreak (March 2019-October 2019). Results: Endurance finishes decreased during the pandemic (459,029 to 42,656 (male: 277,493 to 25,582; female 181,536 to 17,074; all p < 0.001). Similarly, the numbers of endurance events decreased (213 vs. 61 events; p < 0.001). Average marathon finishing times decreased during the pandemic in men (5:18:03 ± 0:16:34 vs. 4:43:08 ± 0:25:08 h:min:s (p = 0.006)) and women (5:39:32 ± 0:19:29 vs. 5:14:29 ± 0:26:36 h:min:s (p = 0.02)). In UER, finishes decreased significantly (580,289 to 110,055; p < 0.001) as did events (5839 to 1791; p < 0.001). Popular event locations in United States, France, UK, and Germany decreased significantly (p < 0.05). All distance and time-limited UER events saw significant decreases (p < 0.05). Conclusions: The COVID-19 pandemic has had a significant effect on endurance and UER, and it is unlikely that running activities return to pre-pandemic levels any time soon. Mitigation strategies and safety protocols should be established.


Assuntos
/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Corrida/estatística & dados numéricos , Fatores de Tempo
2.
Sports Health ; 13(1): 71-77, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32813597

RESUMO

CONTENT: Distance running is one of the most popular physical activities, and running-related injuries (RRIs) are also common. Foot strike patterns have been suggested to affect biomechanical variables related to RRI risks. OBJECTIVE: To determine the effects of foot strike techniques on running biomechanics. DATA SOURCES: The databases of Web of Science, PubMed, EMBASE, and EBSCO were searched from database inception through November 2018. STUDY SELECTION: The initial electronic search found 723 studies. Of these, 26 studies with a total of 472 participants were eligible for inclusion in this meta-analysis. STUDY DESIGN: Systematic review and meta-analysis. LEVEL OF EVIDENCE: Level 4. DATA EXTRACTION: Means, standard deviations, and sample sizes were extracted from the eligible studies, and the standard mean differences (SMDs) were obtained for biomechanical variables between forefoot strike (FFS) and rearfoot strike (RFS) groups using a random-effects model. RESULTS: FFS showed significantly smaller magnitude (SMD, -1.84; 95% CI, -2.29 to -1.38; P < 0.001) and loading rate (mean: SMD, -2.1; 95% CI, -3.18 to -1.01; P < 0.001; peak: SMD, -1.77; 95% CI, -2.21 to -1.33; P < 0.001) of impact force, ankle stiffness (SMD, -1.69; 95% CI, -2.46 to -0.92; P < 0.001), knee extension moment (SMD, -0.64; 95% CI, -0.98 to -0.3; P < 0.001), knee eccentric power (SMD, -2.03; 95% CI, -2.51 to -1.54; P < 0.001), knee negative work (SMD, -1.56; 95% CI, -2.11 to -1.00; P < 0.001), and patellofemoral joint stress (peak: SMD, -0.71; 95% CI, -1.28 to -0.14; P = 0.01; integral: SMD, -0.63; 95% CI, -1.11 to -0.15; P = 0.01) compared with RFS. However, FFS significantly increased ankle plantarflexion moment (SMD, 1.31; 95% CI, 0.66 to 1.96; P < 0.001), eccentric power (SMD, 1.63; 95% CI, 1.18 to 2.08;P < 0.001), negative work (SMD, 2.60; 95% CI, 1.02 to 4.18; P = 0.001), and axial contact force (SMD, 1.26; 95% CI, 0.93 to 1.6; P < 0.001) compared with RFS. CONCLUSION: Running with RFS imposed higher biomechanical loads on overall ground impact and knee and patellofemoral joints, whereas FFS imposed higher biomechanical loads on the ankle joint and Achilles tendon. The modification of strike techniques may affect the specific biomechanical loads experienced on relevant structures or tissues during running.


Assuntos
Pé/fisiologia , Corrida/fisiologia , Tendão do Calcâneo/fisiologia , Tornozelo/fisiologia , Fenômenos Biomecânicos , Análise da Marcha , Humanos , Joelho/fisiologia , Fatores de Risco , Corrida/lesões , Estresse Mecânico
3.
Sports Health ; 13(1): 37-44, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32903164

RESUMO

CONTEXT: Plyometric training has been shown to be beneficial in adolescent overhead athletes. However, existing research on the effects of plyometrics on sport performance has been limited. OBJECTIVE: To systematically review the current literature to investigate whether plyometric training intervention improves upper- and lower-body sport performance. DATA SOURCES: Two electronic databases (MEDLINE and Web of Science) were searched using specific Medical Subject Headings (MeSH) terms up to February 2019, and hand-searching was performed by looking to relevant studies that were cited in other studies. STUDY SELECTION: A total of 932 items were identified and were further assessed for the eligibility in the systematic review. For a study to be eligible, each of the following inclusion criteria had to be met: (1) participants were aged 13 to 18 years and selected from a sports or athletic population and the study (2) involved the evaluation of a plyometric training intervention with an aim to improve sports performance; (3) must have included a control intervention and/or control group; (4) included a quantitative objective measure of sport performance variables concerning throwing, jumping, running, and sprinting; and (5) was published in English. STUDY DESIGN: Systematic review. LEVEL OF EVIDENCE: Level 3. DATA EXTRACTION: A first screening was conducted based on title and abstract of the articles. In the second screening, the full text of the remaining articles was evaluated for the fulfillment of the inclusion criteria. RESULTS: A total of 14 studies were included in this review. The methodological quality of the included studies ranged from low to moderate. There is moderate evidence that plyometric training intervention improves throwing and jumping performances. There is also preliminary evidence that plyometric training intervention improves sprint performance. CONCLUSION: The current evidence suggests that sport performance consisting of throwing capacity, jumping ability, and sprint performance significantly improved due to plyometric training interventions in adolescent overhead athletes.


Assuntos
Desempenho Atlético/fisiologia , Exercício Pliométrico , Esportes Juvenis/fisiologia , Adolescente , Humanos , Extremidade Inferior/fisiologia , Corrida/fisiologia , Extremidade Superior/fisiologia
4.
Sci Total Environ ; 754: 142203, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920413

RESUMO

Enteric viruses exposed to water pose a huge threat to global public health and can lead to waterborne disease outbreaks. A sudden increase in enteric viruses in some water matrices also underpins the prevalence of corresponding waterborne diseases in communities over the same time period. However, few efforts have been focused on water matrices whose viral pollution may best reflect the clinical prevalence in communities. Here, a one-year surveillance of human enteric viruses including Enteroviruses (EnVs), Rotaviruses (HRVs), Astroviruses (AstVs), Noroviruses GII (HuNoVsGII) and Mastadenoviruses (HAdVs) in four representative water matrices: an urban river (UR) running through city, effluent from Wastewater Treatment Plant (EW), raw water for Urban Water Treatment Plant (RW), and tap water (TW) were performed by qPCR. The relationship between the virus detection frequency at each site and their prevalence in clinical PCR assay was further analyzed. We found that the detection frequencies of HRVs, HuNoVsGII, and AstVs in stools peaked in winter, while EnVs peaked in autumn. No EnVs occurred in EW, RW, or TW, but HuNoVsGII and AstVs occurred intensively in winter. For UR, all types of enteric viruses could be detected and the levels of acute gastroenteritis viruses (HRVs, HuNoVsGII, AstVs, and HAdVs) were highest in autumn or winter, whereas EnVs peaked in summer. In terms of correlation analyses, only HRVs and HuNoVsGII levels in UR showed a strong positive correlation with their prevalence in clinical stool samples. This study indicated that HRVs and HuNoVsGII levels in URs may mirror the local virus prevalence, thereby implying the possibility of revealing their local epidemiology by monitoring them in the URs.


Assuntos
Infecções , Norovirus , Rotavirus , Corrida , Cidades , Humanos , Prevalência , Rios
5.
Eur Rev Med Pharmacol Sci ; 24(24): 13049-13055, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33378057

RESUMO

OBJECTIVE: This review was conducted to systematically analyze the effects of aerobic exercise on immunological biomarkers to provide safe aerobic exercise recommendations and specifications for patients with COVID-19. MATERIALS AND METHODS: A systematic search was conducted through MEDLINE (PubMed), Science Direct, Web of Science, Scopus, Cochrane Library, and SciELO databases. The search included the following keywords "immune system", "immune cell", or "immune function"; "aerobic training", "aerobic exercise", or "physical activity"; "human" or "adult"; and "cytokine", "killer cell", "T cell", "interleukin", "lymphocyte", "leukocyte" or "adhesion molecule". RESULTS: Eleven studies met the inclusion and exclusion criteria of this search. The most used exercise prescriptions included walking, cycling, or running. The duration of exercise ranged from 18 to 60 min with an intensity of 55% to 80% of VO2max or 60%-80% of maximum heart rate. The frequency range was 1 to 3 times/week. The mainly increased immunological biomarkers included leukocytes, lymphocytes, neutrophils, monocytes, eosinophils, IL-6, CD16-56, CD16, CD4, CD3, CD8, and CD19. CONCLUSIONS: This review demonstrated that patients with COVID-19 should follow a regular program of aerobic exercise for 20-60 min. This program should be in the form of cycling or walking with an intensity of 55%-80% VO2max or 60%-80% of maximum heart rate. This program should be repeated 2-3 sessions/week. These previous parameters could safely enhance immune functions without producing any exhaustion.


Assuntos
/reabilitação , Terapia por Exercício/métodos , Exercício Físico/fisiologia , Ciclismo , Citocinas/imunologia , Humanos , Imunoglobulinas/imunologia , Contagem de Leucócitos , Contagem de Linfócitos , Neutrófilos , Consumo de Oxigênio , Corrida , Caminhada
6.
PLoS One ; 15(12): e0242640, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33373386

RESUMO

To examine the differential mechanobiological responses of specific resident tendon cells, we developed an in vivo model of whole-body irradiation followed by injection of either tendon stem/progenitor cells (TSCs) expressing green fluorescent protein (GFP-TSCs) or mature tenocytes expressing GFP (GFP-TNCs) into the patellar tendons of wild type C57 mice. Injected mice were subjected to short term (3 weeks) treadmill running, specifically moderate treadmill running (MTR) and intensive treadmill running (ITR). In MTR mice, both GFP-TSC and GFP-TNC injected tendons maintained normal cell morphology with elevated expression of tendon related markers collagen I and tenomodulin. In ITR mice injected with GFP-TNCs, cells also maintained an elongated shape similar to the shape found in normal/untreated control mice, as well as elevated expression of tendon related markers. However, ITR mice injected with GFP-TSCs showed abnormal changes, such as cell morphology transitioning to a round shape, elevated chondrogenic differentiation, and increased gene expression of non-tenocyte related genes LPL, Runx-2, and SOX-9. Increased gene expression data was supported by immunostaining showing elevated expression of SOX-9, Runx-2, and PPARγ. This study provides evidence that while MTR maintains tendon homeostasis by promoting the differentiation of TSCs into TNCs, ITR causes the onset of tendinopathy development by inducing non-tenocyte differentiation of TSCs, which may eventually lead to the formation of non-tendinous tissues in tendon tissue after long term mechanical overloading conditions on the tendon.


Assuntos
Condrócitos/citologia , Células-Tronco/citologia , Tendinopatia/patologia , Tendões/patologia , Tenócitos/citologia , Animais , Biomarcadores/metabolismo , Diferenciação Celular , Forma Celular , Rastreamento de Células , Condrócitos/metabolismo , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Teste de Esforço , Feminino , Regulação da Expressão Gênica , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Lipase Lipoproteica/genética , Lipase Lipoproteica/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , PPAR gama/genética , PPAR gama/metabolismo , Condicionamento Físico Animal/efeitos adversos , Corrida , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Células-Tronco/metabolismo , Tendinopatia/etiologia , Tendinopatia/genética , Tendinopatia/metabolismo , Tendões/metabolismo , Tenócitos/metabolismo
7.
BMJ ; 371: m4561, 2020 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-33328169

RESUMO

OBJECTIVE: To estimate the daily dietary energy intake for me to maintain a constant body weight. How hard can it be? DESIGN: Very introspective study. SETTING: At home. In lockdown. (Except every Tuesday afternoon and Saturday morning, when I went for a run.) PARTICIPANTS: Me. n=1. MAIN OUTCOME MEASURES: My weight, measured each day. RESULTS: Sleeping, I shed about a kilogram each night (1.07 (SD 0.25) kg). Running 5 km, I shed about half a kilogram (0.57 (SD 0.15) kg). My daily equilibrium energy intake is about 10 000 kJ (10 286 (SD 201) kJ). Every kJ above (or below) 10 000 kJ adds (or subtracts) about 40 mg (35.4 (SD 3.2) mg). CONCLUSIONS: Body weight data show persistent variability, even when the screws of control are tightened and tightened.


Assuntos
Ingestão de Energia , Corrida , Peso Corporal , Metabolismo Energético , Humanos
8.
Harefuah ; 159(11): 781-782, 2020 Nov.
Artigo em Hebraico | MEDLINE | ID: mdl-33210845

RESUMO

INTRODUCTION: A 16 years old girl presented with gradual foot pain after running 2 kilometers. Conservative treatment that consisted of rest and high dose of analgesia had no effect. An MRI scan revealed a partial tear of the abductor hallucis muscle with diffuse edema in the compartment. Under general anesthesia compartmental pressure was measured. The involved compartment's pressure was 130 mm/hg while the contralateral foot measured 10 mm/hg. Immediate fasciotomy was performed with instant pain relief. No analgesics were needed following surgery. Compartment syndrome usually develops following trauma. In unusual cases the syndrome can appear due to other causes, such as muscle tear and present with different clinical signs and rates of presentation. Exertional compartment syndrome presents in the pediatric population, but can rarely present in the foot. High clinical suspicion and awareness can help the diagnosis in challenging cases.


Assuntos
Síndromes Compartimentais , Corrida , Adolescente , Criança , Síndromes Compartimentais/diagnóstico , Síndromes Compartimentais/etiologia , Síndromes Compartimentais/terapia , Fasciotomia , Feminino , , Humanos , Dor/diagnóstico , Dor/etiologia
9.
PLoS One ; 15(10): e0239852, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33027311

RESUMO

Studies on the paradigm of the preferred movement path are scarce, and as a result, many aspects of the paradigm remain elusive. It remains unknown, for instance, how muscle activity adapts when differences in joint kinematics, due to altered running conditions, are of low / high magnitudes. Therefore, the purpose of this work was to investigate changes in muscle activity of the lower extremities in runners with minimal (≤ 3°) or substantial (> 3°) mean absolute differences in the ankle and knee joint angle trajectories when subjected to different running footwear. Mean absolute differences in the integral of the muscle activity were quantified for the tibialis anterior (TA), peroneus longus (PL), gastrocnemius medialis (GM), soleus (SO), vastus lateralis (VL), and biceps femoris (BF) muscles during over ground running. In runners with minimal changes in 3D joint angle trajectories (≤ 3°), muscle activity was found to change drastically when comparing barefoot to shod running (TA: 35%; PL: 11%; GM: 17%; SO: 10%; VL: 27%; BF: 16%), and minimally when comparing shod to shod running (TA: 10%; PL: 9%; GM: 13%; SO: 8%; VL: 8%; BF: 12%). For runners who showed substantial changes in joint angle trajectories (> 3°), muscle activity changed drastically in barefoot to shod comparisons (TA: 39%; PL: 14%; GM: 16%; SO: 16%; VL: 25%; BF: 24%). It was concluded that a movement path can be maintained with small adaptations in muscle activation when running conditions are similar, while large adaptations in muscle activation are needed when running conditions are substantially different.


Assuntos
Contração Muscular , Corrida , Sapatos/normas , Adulto , Feminino , Humanos , Masculino , Músculo Esquelético/fisiologia
10.
Nat Commun ; 11(1): 4936, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33024098

RESUMO

Wearable exercise trackers provide data that encode information on individual running performance. These data hold great potential for enhancing our understanding of the complex interplay between training and performance. Here we demonstrate feasibility of this idea by applying a previously validated mathematical model to real-world running activities of  ≈ 14,000 individuals with ≈ 1.6 million exercise sessions containing duration and distance, with a total distance of ≈ 20 million km. Our model depends on two performance parameters: an aerobic power index and an endurance index. Inclusion of endurance, which describes the decline in sustainable power over duration, offers novel insights into performance: a highly accurate race time prediction and the identification of key parameters such as the lactate threshold, commonly used in exercise physiology. Correlations between performance indices and training volume and intensity are quantified, pointing to an optimal training. Our findings hint at new ways to quantify and predict athletic performance under real-world conditions.


Assuntos
Modelos Teóricos , Corrida/fisiologia , Atletas , Big Data , Exercício Físico/fisiologia , Humanos , Ácido Láctico/metabolismo , Consumo de Oxigênio , Resistência Física/fisiologia , Dispositivos Eletrônicos Vestíveis
11.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 461-464, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018027

RESUMO

During running, interactions were considered between three physiological oscillators - the heart, breaths, and steps. During intense exercise, the oscillations of all three systems are close to regular, producing good conditions to observe and characterise synchronization. The origin, as well as any physiological significance, of synchronization between these systems during running is not fully accepted or understood. Furthermore, the impact on synchronization of controlling both breathing and step rate has not been previously reported in detail. This study aims to measure cardiolocomotor, cardiorespiratory and respiratory- locomotor synchronization during different running protocols. Breathing was controlled by taking a fixed number of steps per breath (ratios of 5:1 and 3:1). Step rate was then guided at rates close to active heart rate, to instigate 1:1 phase-locking. Instantaneous phase difference quantified synchronization episodes. We have successfully observed all three forms of synchronization during all running protocols. Furthermore, coupling between heartbeats and steps was more pronounced when step rate was guided, and both cardiorespiratory and respiratory-locomotor coupling were extended when breathing rate was fixed to steps. These are exciting initial results from a novel experimental design, highlighting the complex interconnection that exists between these three systems during running, and the conditions to best observe the phenomena.


Assuntos
Corrida , Coração , Frequência Cardíaca , Humanos , Respiração , Taxa Respiratória
12.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4811-4814, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019067

RESUMO

Despite extensive rehabilitation, nearly half of all post-anterior cruciate ligament reconstruction (ACLR) individuals are unable to perform dynamic tasks at the level they did prior to their injury. This inability can be attributed to unresolved neuromuscular deficits that manifest as altered limb dynamics. While traditional discrete metrics; such as peak vertical ground reaction force (vGRF) and peak knee flexion angle, have been used to successfully differentiate between healthy and pathological running dynamics, recent studies have shown that non-traditional metrics derived from autoregressive (AR) modeling and Smoothed Pseudo Wigner-Ville (SPWV) analysis techniques can also successfully delineate between healthy and pathological populations and could potentially possess greater sensitivity than the traditional metrics. Thus, the objective of this study was to compare the performance of classification models generated from traditional and nontraditional metrics collected from healthy controls and post-ACLR individuals during a running protocol. We hypothesized that the non-traditional metric-based classification model would outperform the traditional metric based model. Thirty-one controls and 31 post-ACLR individuals performed a running protocol from which the traditional metrics - peak vGRF, linear vGRF loading rate and peak knee flexion angle - and nontraditional metrics - dynamic vGRF ratio, AR model coefficients, and a SPWV derived low frequency-high frequency ratio - were extracted from vGRF and knee flexion running waveforms. The results indicated that a fine Gaussian SVM classification model derived from the non-traditional metrics had an accuracy of 87%, specificity of 83% and sensitivity of 61% and it outperformed the classification model derived from traditional metrics. These findings indicate that additional, valuable information can be ascertained from non-traditional metrics that evaluate waveform dynamics. Additionally, it suggests that this or similar models can be used to track the restoration of healthy running dynamics in post-ACLR individuals during rehabilitation.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Corrida , Lesões do Ligamento Cruzado Anterior/cirurgia , Fenômenos Biomecânicos , Humanos
13.
J Strength Cond Res ; 34(10): 2760-2768, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32986391

RESUMO

Vera-Assaoka, T, Ramirez-Campillo, R, Alvarez, C, Garcia-Pinillos, F, Moran, J, Gentil, P, and Behm, D. Effects of maturation on physical fitness adaptations to plyometric drop jump training in male youth soccer players. J Strength Cond Res 34(10): 2760-2768, 2020-The objective of this study was to compare the effects of maturation on physical fitness adaptations to a twice weekly, 7-week plyometric drop jump training program. Seventy-six young male soccer players (aged 10-16 years) participated in this randomized controlled trial. Before and after the intervention, a physical fitness test battery was applied (countermovement jump; drop jump from 20 to 40 cm; 5 multiple bounds test; 20-m sprint time; change of direction speed; 2.4-km running time-trial; 5 repetition maximum [RM] squat; and maximal kicking distance). Participants were randomly divided into an active soccer-control group (CG) with Tanner stage maturation of 1-3 (CG-early; n = 16) or Tanner stage 4-5 (CG-late; n = 22), and to plyometric drop jump training groups with Tanner stage 1-3 (plyometric jump training [PJT]-early; n = 16) or 4-5 (PJT-late; n = 22). The analysis of variance and effect size (ES) measures revealed that when compared with their age-matched controls, the PJT-early (ES = 0.39-1.58) and PJT-late (ES = 0.21-0.65) groups showed greater improvements (p < 0.05) in sprint time, 2.4-km running time-trial, change of direction speed, 5RM squat, jumping, and kicking distance. The PJT-early exceeded the PJT-late group with greater (p < 0.05) improvements in drop jump from 20 cm (ES = 1.58 vs. 0.51) and 40 cm (ES = 0.71 vs. 0.4) and kicking distance (ES = 0.95 vs. 0.65). Therefore, a 7-week plyometric drop jump training program was effective in improving physical fitness traits in both younger and older male youth soccer players, with greater jumping and kicking adaptations in the less-mature athletes.


Assuntos
Adaptação Fisiológica , Fatores Etários , Atletas , Exercício Pliométrico , Futebol , Adolescente , Desempenho Atlético , Criança , Teste de Esforço , Humanos , Masculino , Aptidão Física , Corrida
14.
J Strength Cond Res ; 34(10): 2805-2814, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32986393

RESUMO

Hills, SP, Barrett, S, Busby, M, Kilduff, LP, Barwood, MJ, Radcliffe, JN, Cooke, CB, and Russell, M. Profiling the post-match top-up conditioning practices of professional soccer substitutes: An analysis of contextual influences. J Strength Cond Res 34(10): 2805-2814, 2020-Soccer practitioners implement "top-up" conditioning sessions to compensate for substitutes' limited match-play exposure. Although perceived to be valuable for reducing injury risk and augmenting positive physical adaptations, little research has considered the demands of post-match top-up training. To quantify post-match top-up responses, 31 professional soccer players wore 10 Hz microelectromechanical systems after 37 matches whereby they were selected in the match-day squad as substitutes (184 observations; 6 ± 5 observations·player). Linear mixed models and effect sizes (ES) assessed the influence of contextual factors on 23 physical performance variables. Top-ups lasted 17.13 ± 7.44 minutes, eliciting total and high-speed distances of 1.7 ± 6.2 km and 0.4 ± 1.7 km, respectively. Each contextual factor (i.e., position, substitution timing, match location, result, time of day, stage of the season, and fixture density) influenced at least 4 of the dependent variables profiled (p ≤ 0.05). Top-up duration; total, moderate-speed, and low-speed distance; and the number of repeated high-intensity efforts were greater for unused vs. used substitutes (ES: 0.38-0.73, small to moderate). Relative to away matches, home top-ups elicited heightened total, low-speed, and high-speed distances, alongside more moderate-speed accelerations and decelerations, and repeated high-intensity efforts (ES: 0.25-0.89, small to moderate). Although absolute and relative running distances were generally the highest when the fixture density was low, the greatest acceleration and deceleration demands were observed during the most congested fixture periods. Late-season top-ups typically elicited lower absolute physical responses than early and mid-season sessions. These data provide important information for practitioners when considering the aims and design of substitute top-up conditioning sessions, particularly with reference to contextual influences.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Futebol/fisiologia , Aceleração , Adaptação Fisiológica , Humanos , Modelos Lineares , Sistemas Microeletromecânicos , Corrida/fisiologia
15.
PLoS One ; 15(9): e0239091, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32915897

RESUMO

INTRODUCTION: To investigate the glycaemic response, macronutrient intake and insulin management in people with type 1 diabetes (T1D) compared to healthy individuals around a running competition. MATERIAL AND METHODS: This was a single-centre, prospective, controlled observational study performed in individuals with T1D and healthy people. 24 people (12 T1D) were included in this study (age: T1D 41±12 vs. healthy 38±6 years, females: 3 vs. 6, BMI: 25.53.0 vs. 22.9±2.8 kg/m2). Both groups received an intermittently scanned continuous glucose monitoring (isCGM; FreeStyle Libre 1, Abbott, USA) system to assess glycaemia 24 hours before, during and 24 hours after a running competition. During this period, participants recorded their food intake and insulin administration. Data were analysed via ANOVA and mixed model analyses with post-hoc testing (p≤0.05). RESULTS: For overall glycaemic ranges in comparison of groups, significant differences were found for time in range (T1D 63±21% vs. healthy 89±13%, p = 0.001), time above range (TAR) 1 (T1D 21±15% vs. healthy 0±0%, p<0.001) and TAR 2 (T1D 8 [0-16%] vs. healthy 0±0%, p<0.001). When glycaemic variability was assessed, people with T1D had a higher glycaemic variability compared to healthy individuals (p<0.0001). Basal insulin dose was significantly reduced when compared against the regular pre-study basal insulin dose (pre-study 22±6 vs. pre-competition day 11±9 (-50±41%), p = 0.02; competition day 15±5 (-32± 1%)). CONCLUSION: People with T1D have impaired glucose responses around a running competition compared to healthy individuals. However, basal insulin dose reductions were sufficient to prevent further dysglycaemia. CLINICAL TRIAL ID: drks.de; DRKS00019886.


Assuntos
Glicemia/fisiologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Ingestão de Alimentos/fisiologia , Insulina/administração & dosagem , Corrida/fisiologia , Adolescente , Adulto , Idoso , Glicemia/análise , Glicemia/efeitos dos fármacos , Automonitorização da Glicemia/estatística & dados numéricos , Estudos de Casos e Controles , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/fisiopatologia , Relação Dose-Resposta a Droga , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
16.
PLoS One ; 15(9): e0238846, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32915883

RESUMO

The study aimed at assessing the acute physiological effects of running a 65-km vs a 107-km mountain ultramarathon. Nineteen athletes (15 males and 4 females) from the shorter race and forty three athletes (26 males and 17 females) from the longer race were enrolled. Body weight, respiratory and lower limb strength were assessed before and after the race. Blood samples were obtained before, after and 24-h post-race. Body weight loss did not differ between races. A decrease in squat jump height (p<0.01; d = 1.4), forced vital capacity (p<0.01; d = 0.5), forced expiratory volume in 1 s (p<0.01; d = 0.6), peak inspiratory flow (p<0.01; d = 0.6) and maximal inspiratory pressure (p<0.01; d = 0.8) was observed after the longer race; while, after the shorter race only maximal inspiratory pressure declined (p<0.01; d = 0.5). Greater post-race concentrations of creatine kinase (p<0.01; d = 0.9) and C-reactive protein (p<0.01; d = 2.3) were observed following the longer race, while high-sensitivity cardiac troponin was higher after the shorter race (p<0.01; d = 0.3). Sodium decreased post-competition only after the shorter race (p = 0.02; d = 0.6), while creatinine increased only following the longer race (p<0.01; d = 1.5). In both groups, glomerular filtration rate declined at post-race (longer race: p<0.01, d = 2.1; shorter race: p = 0.01, d = 1.4) and returned to baseline values at 24 h post-race. In summary, expiratory and lower-limb fatigue, and muscle damage and inflammatory response were greater following the longer race; while a higher release of cardiac troponins was observed after the shorter race. The alteration and restoration of renal function was similar after either race.


Assuntos
Biomarcadores/sangue , Fadiga/fisiopatologia , Extremidade Inferior/fisiopatologia , Pulmão/fisiopatologia , Força Muscular , Resistência Física/fisiologia , Corrida , Adulto , Atletas/estatística & dados numéricos , Creatina Quinase/sangue , Creatinina/sangue , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Testes de Função Respiratória , Capacidade Vital
17.
Artigo em Inglês | MEDLINE | ID: mdl-32933124

RESUMO

Research has shown that cold air exercise causes significant respiratory dysfunction, especially in female athletes. However, how female and male athletes respond to cold air exercise is not known. Thus, we aimed to compare acute respiratory responses (function, recovery and symptoms) in males and females after high-intensity cold air exercise. Eighteen (nine female) athletes completed two environmental chamber running trials at 0 °C and -20 °C (humidity 34 ± 5%) on different days in a randomized starting order. Spirometry was performed pre, 3, 6, 10, 15 and 20 min post. Respiratory symptoms were measured posttrial and heart rate and rating of perceived exertion were assessed during each trial. No significant differences in delta change (pre to post) were found at either temperature between sexes for FEV1, FVC, FEF50% and FEF25-75%. At -20 °C, FEV1 decreased similarly in both sexes (males: 7.5%, females: 6.3%) but not at 0 °C, p = 0.003. Postexertion respiratory function recovery and reported symptoms were not different between sexes at either temperature. These results indicate no sex-based differences in acute respiratory responses (function, recovery and symptoms) to cold air exercise. However, intense exercise at -20 °C is challenging to the respiratory system in both sexes and may lead to altered respiratory responses compared to mild winter conditions like 0 °C.


Assuntos
Atletas , Temperatura Baixa , Exercício Físico/fisiologia , Corrida/fisiologia , Adulto , Feminino , Humanos , Masculino , Espirometria
18.
PLoS One ; 15(8): e0238569, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32866216

RESUMO

Validation of heart rate responses in wearable technology devices is generally composed of laboratory-based protocols that are steady state in nature and as a result, high accuracy measures are returned. However, there is a need to understand device validity in applied settings that include varied intensities of exercise. The purpose was to determine concurrent heart rate validity during trail running. Twenty-one healthy participants volunteered (female n = 10, [mean (SD)]: age = 31 [11] years, height = 173.0 [7] cm, mass = 75.6 [13] kg). Participants were outfitted with wearable technology devices (Garmin Fenix 5 wristwatch, Jabra Elite Sport earbuds, Motiv ring, Scosche Rhythm+ forearm band, Suunto Spartan Sport watch with accompanying chest strap) and completed a self-paced 3.22 km trail run while concurrently wearing a criterion heart rate strap (Polar H7 heart rate monitor). The trail runs were out-and-back with the first 1.61 km in an uphill direction, and the 1.61 return being downhill in nature. Validity was determined through three methods: Mean Absolute Percent Error (MAPE), Bland-Altman Limits of Agreement (LOA), and Lin's Concordance Coefficient (rC). Validity measures overall are as follows: Garmin Fenix 5 (MAPE = 13%, LOA = -32 to 162, rC = 0.32), Jabra Elite Sport (MAPE = 23%, LOA = -464 to 503, rC = 0.38), Motiv ring (MAPE = 16%, LOA = -52 to 96, rC = 0.29), Scosche Rhythm+ (MAPE = 6%, LOA = -114 to 120, rC = 0.79), Suunto Spartan Sport (MAPE = 2%, LOA = -62 to 61, rC = 0.96). All photoplethysmography-based (PPG) devices displayed poor heart rate agreement during variable intensity trail running. Until technological advances occur in PPG-based devices allowing for acceptable agreement, heart rate in outdoor environments should be obtained using an ECG-based chest strap that can be connected to a wristwatch or other comparable receiver.


Assuntos
Determinação da Frequência Cardíaca/instrumentação , Determinação da Frequência Cardíaca/métodos , Frequência Cardíaca/fisiologia , Corrida/fisiologia , Tecnologia/instrumentação , Tecnologia/métodos , Adulto , Exercício Físico/fisiologia , Teste de Esforço/instrumentação , Teste de Esforço/métodos , Feminino , Monitores de Aptidão Física , Humanos , Masculino , Fotopletismografia/métodos , Dispositivos Eletrônicos Vestíveis
19.
Artigo em Inglês | MEDLINE | ID: mdl-32872427

RESUMO

The study aimed to investigate the correlations among immune, haematological, endocrinological markers and fitness parameters, and assess if the physiological parameters could be a predictor of fitness values. Anthropometric, physical evaluations (countermovement jump-CMJ, 10 m sprint, VO2max, repeated sprint ability-RSA total time and index) and determination of blood (IL-6, IL-10, IL-17A and tumour necrosis factor) and salivary (testosterone and cortisol) samples parameters in 28 young male soccer players (age: 13.0 ± 0.2 years, body mass index (BMI): 19.5 ± 2.2 kg/m2) were analysed. To evaluate the dependence of the variables related to athletic performance, multiple linear regression with backward stepwise elimination was considered. A significant regression equation was found in CMJ (F(5,16) = 9.86, p < 0.001, R2 adjusted = 0.679) and in the RSA index (F(5,16) = 15.39, p < 0.001, R2 adjusted = 0.774) considering only five variables, in a 10 m sprint (F(4,17) = 20.25, p < 0.001, R2 adjusted = 0.786) and in the RSA total time (F(4,17) = 15.31, p < 0.001, R2 adjusted = 0.732) considering only four variables and in VO2max (F(9,12) = 32.09, p < 0.001, R2 adjusted = 0.930) considering nine variables. Our study suggests the use of regression equations to predict the fitness values of youth soccer players by blood and saliva samples, during different phases of the season, short periods of match congestion or recovery from an injury.


Assuntos
Biomarcadores , Aptidão Física , Corrida , Futebol , Adolescente , Criança , Teste de Esforço , Humanos , Masculino , Projetos Piloto
20.
PLoS One ; 15(9): e0238580, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32911530

RESUMO

The change of direction (COD) ability is an important task-specific skill for success in team sports, dependent on both strength and reactive strength. The sprint approaching the COD and degrees of the turn are factors influencing the specificity of the COD. Thus, CODs have been suggested to be categorized as force- (> 90°) and velocity-dominant (< 90°) dependent on the degree of the turn. When training programmes fail to provide a significant increase in COD performance, it is often due to neglecting the task-specific demands of the COD. As such, 23 male football players volunteered to complete a randomized controlled trial, investigating the association of maximal strength and power performance with performance in a force- (180°) and velocity-dominant (45°) COD, with a 4 m and 20 m sprint approach. Three strength and three plyometric exercises, matched in movement patterns, were used. Muscle activity of the different conditions was also compared. The correlational analysis revealed that better performance in the plyometric tests were associated with less time to complete both force- and velocity-dominant CODs, supported by similarities in muscle activation. None of the performances in strength exercises correlated to COD performance, due to the slow contraction velocity of maximal lifts. It was concluded that plyometrics share more physical similarities with CODs than the strength exercises.


Assuntos
Desempenho Atlético , Força Muscular , Exercício Pliométrico/métodos , Corrida , Adulto , Humanos , Masculino , Músculo Esquelético/fisiologia , Aptidão Física , Futebol , Adulto Jovem
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