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1.
Euro Surveill ; 25(36)2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32914744

RESUMO

In March 2020, we observed an outbreak of COVID-19 among a relatively homogenous group of 199 young (median age 21 years; 87% men) Swiss recruits. By comparing physical endurance before and in median 45 days after the outbreak, we found a significant decrease in predicted maximal aerobic capacity in COVID-19 convalescent but not in asymptomatically infected and SARS-CoV-2 naive recruits. This finding might be indicative of lung injury after apparently mild COVID-19 in young adults.


Assuntos
Infecções por Coronavirus/diagnóstico , Coronavirus/isolamento & purificação , Exercício Físico/fisiologia , Lesão Pulmonar/etiologia , Consumo de Oxigênio , Resistência Física/fisiologia , Pneumonia Viral/diagnóstico , Ventilação Pulmonar/fisiologia , Adulto , Infecções Assintomáticas , Betacoronavirus , Convalescença , Coronavirus/genética , Infecções por Coronavirus/epidemiologia , Surtos de Doenças , Feminino , Humanos , Masculino , Militares , Pandemias , Resistência Física/imunologia , Aptidão Física , Pneumonia Viral/epidemiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco , Suíça/epidemiologia , Adulto Jovem
2.
PLoS One ; 15(8): e0237706, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32817656

RESUMO

Endurance-trained sled dogs provide a unique translational model to characterize changes in hematologic and serum biochemical analytes due to the aging process. The primary objective of this study was to determine the effect of age and sex on specific hematologic and serum biochemical parameters in the endurance trained sled dog. Longitudinal and cross-sectional data were analyzed from 9,746 blood and serum samples from 4,804 dogs collected over 7 years as part of the Iditarod Trail Sled Dog Race pre-race examination program. Mixed models analysis was used for statistical analysis and P < 0.01 was considered significant. Dogs ranged from 1-12 years of age and 39% were female. Serum total calcium and phosphorus concentrations and white blood cell count decreased nonlinearly to asymptotic values by 6.6, 3.1, and 6.9 years of age, respectively, equivalent to estimated physiologic ages in human years of 44, 27, and 46 years. Serum glucose concentrations reached their lowest value at 7.8 years of age, equivalent to an estimated human physiologic age of 50 years, after which time the concentration increased. Serum globulin concentrations increased with age, but nonlinearly for females and linearly for males. Most sex-related differences were <5%; however, females had lower serum urea nitrogen (14.7%) and creatinine (7.3%) concentrations, lower serum alanine aminotransferase activity (16.6%), and higher serum total bilirubin concentration (12.8%) and platelet count (6.0%). The endurance-trained sled dog provides an excellent model to separate the physiologic effects of age from those of a sedentary lifestyle on hematologic and serum biochemical analytes.


Assuntos
Treino Aeróbico , Condicionamento Físico Animal/fisiologia , Resistência Física/fisiologia , Corrida/fisiologia , Animais , Nitrogênio da Ureia Sanguínea , Doenças do Cão/sangue , Doenças do Cão/fisiopatologia , Cães , Feminino , Testes Hematológicos , Humanos , Masculino , Soroglobulinas/metabolismo
3.
Clin Interv Aging ; 15: 1035-1043, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32636618

RESUMO

Background: Geriatric rehabilitation programs primarily aim at an increase of mobility and functional autonomy of the elderly. The cardiovascular effects of these programs, however, remain elusive. Since regular physical exercise is associated with numerous beneficial cardiovascular effects including a reduction of blood pressure (BP), the present prospective study investigates the hemodynamic effects of a representative standardized rehabilitation program. Methods: A total of 74 subjects who were hospitalized in a German university hospital for geriatric rehabilitation were enrolled in the study. Peripheral BP, central aortic BP, 24h-ambulatory BP, heart rate and pulse wave velocity as a measure of arterial stiffness were assessed at admission and before discharge from the hospital. The program contained 4-5 sessions of physical activity of individualized intensity per week (≥30 min/session, eg, walking, cycling, stair rising). Results: The mean age of the study population was 82.4±6.9 years; all patients suffered from arterial hypertension (stage 2-3) with a median number of three antihypertensive drugs. The most frequent cause for admission was injurious falls. The mean duration of the rehabilitation program was 17 days and comprised at least 20 physical activity sessions including occupational therapy. The program led to a significant improvement of mobility (Timed Up & Go 29.5±18.5 vs 19.1 ±9.3 s, p<0.001) and Barthel index of activities of daily living score (46.6±19.1 vs 69.8±16.5, p<0.001). Peripheral systolic BP decreased from 135.4±19.0 mmHg at baseline to 129.0±18.4 mmHg at follow-up (p=0.03), whereas peripheral diastolic BP, central aortic BP, 24h-ambulatory BP, heart rate and pulse wave velocity as a measure of arterial stiffness were not significantly altered (p>0.05 each). Conclusion: The present representative standardized geriatric rehabilitation program was able to improve mobility, which showed a mild effect on systolic BP but did not affect 24h-ambulatory BP.


Assuntos
Exercício Físico , Hemodinâmica , Hipertensão/reabilitação , Resistência Física/fisiologia , Idoso , Idoso de 80 Anos ou mais , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/fisiologia , Feminino , Humanos , Hipertensão/fisiopatologia , Masculino , Estudos Prospectivos , Análise de Onda de Pulso , Rigidez Vascular/fisiologia
4.
PLoS One ; 15(7): e0236658, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32722683

RESUMO

The purposes of this study were 1) to analyse the different pacing behaviours based on athlete's performance and 2) to determine whether significant differences in each race split and the runner's performance implied different race profiles. A total of 2295 runners, which took part in Berlin's marathon (2017), met the inclusion criteria. 4 different groups were created based on sex and performance. Men: Elite (<02:19:00 h), Top 1 (<02:30:00 h), Top 2 (<02:45:00 h) and Top 3 (<03:00:00 h); women: Elite (02:45:00 h), Top 1 (<03:00:00 h), Top 2 (<03:15:00 h), Top 3 (<03:30:00 h). With the aim of comparing the pacing between sex and performance the average speed was normalized. In men, no statistically significant changes were found between performance group and splits. A large number of significant differences between splits and groups were found amongst women: 5-10 km Top 2 vs Top 3 (P = 0.0178), 10-15 km Top1 vs Top 2 (P = 0.0211), 15-20 km Top1 vs Top 2 (P = 0.0382), 20-21.1 km Elite vs Top 2 (P = 0.0129); Elite vs Top 3 (P = 0.0020); Top1 vs Top 2 (P = 0.0233); Top 1 vs Top 3 (P = 0.0007), 25-30 km Elite vs Top 2 (P = 0.0273); Elite vs Top 3 (P = 0.0156), 30-35 km Elite vs Top 2 (P = 0.0096); Top 1 vs Top 2 (P = 0.0198); Top2 vs Top3 (P = 0.0069). In men there were little significant differences based on athletes' performance which implied a similar pacing behaviour. Women presented numerous differences based on their performance which suggested different pacing behaviours.


Assuntos
Desempenho Atlético , Resistência Física/fisiologia , Corrida/fisiologia , Adulto , Feminino , Humanos , Masculino , Caracteres Sexuais , Adulto Jovem
5.
Artigo em Inglês | MEDLINE | ID: mdl-32645886

RESUMO

The aim of this study was to analyze the changes in biochemical markers of oxidative stress and muscle damage, as well as psychomotor abilities during a military survival training. The study included 15 soldiers of special unit (SU), that completed 48 h military survival training combined with sleep deprivation. Before the training (P1), after 24 h (P2), and after 48 h of training (P3), blood samples were taken to measure biochemical markers. At the same time points, the measurements of divided attention and handgrip strength were conducted. Glutathione peroxidase activity decreased significantly at P3, in comparison with P1 and P2 (p < 0.0001), however, no changes were observed in other biochemical markers (i.e., lipid hydroperoxides, creatine kinase and superoxide dismutase activity) throughout the survival training (p > 0.05). The divided attention index was improved significantly at P2 and P3, as compared to P1 (p < 0.05). A tendency to change in maximum strength was found during the training period (main time effect; p = 0.08). Moreover, the strength differentiation (i.e., 50% maximum strength; 50%max) was higher at P3 than at P1 and P2 (p < 0.05). In conclusion, the 48 h survival training in the SU soldiers does not cause oxidative stress or muscle tissue damage, as well as any deterioration, and even improvement in psychomotor abilities. However, the change in strength differentiation (i.e., the production above 60%max instead of target 50%max) after the training may point to deterioration in motor control. Although it should be confirmed in further study with a more numerous group of soldiers, our findings indicate that the special unit soldiers will be able to perform, in a correct manner, specialized tasks related to their long-term activities, especially those which require divided attention. However, participation in long-term survival training, even with low workload, combined with sleep deprivation, results in a deterioration in motor control which may indicate the relevance of monitoring coordination motor abilities/skills in the training process of special unit soldiers.


Assuntos
Exercício Físico/fisiologia , Militares , Destreza Motora , Estresse Oxidativo/fisiologia , Privação do Sono , Sobrevida/fisiologia , Biomarcadores/sangue , Força da Mão/fisiologia , Humanos , Resistência Física/fisiologia
6.
Am J Physiol Endocrinol Metab ; 319(2): E447-E454, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32691630

RESUMO

The aim of the present study was to determine if the training status decreases inflammation, slows down senescence, and preserves telomere health in skeletal muscle in older compared with younger subjects, with a specific focus on satellite cells. Analyses were conducted on skeletal muscle and cultured satellite cells from vastus lateralis biopsies (n = 34) of male volunteers divided into four groups: young sedentary (YS), young trained cyclists (YT), old sedentary (OS), and old trained cyclists (OT). The senescence state and inflammatory profile were evaluated by telomere dysfunction-induced foci (TIF) quantification, senescence-associated ß-galactosidase (SA-ß-Gal) staining, and quantitative (q)RT-PCR. Independently of the endurance training status, TIF levels (+35%, P < 0.001) and the percentage of SA-ß-Gal-positive cells (+30%, P < 0.05) were higher in cultured satellite cells of older compared with younger subjects. p16 (4- to 5-fold) and p21 (2-fold) mRNA levels in skeletal muscle were higher with age but unchanged by the training status. Aging induced higher CD68 mRNA levels in human skeletal muscle (+102%, P = 0.009). Independently of age, both trained groups had lower IL-8 mRNA levels (-70%, P = 0.011) and tended to have lower TNF-α mRNA levels (-40%, P = 0.10) compared with the sedentary subjects. All together, we found that the endurance training status did not slow down senescence in skeletal muscle and satellite cells in older compared with younger subjects despite reduced inflammation in skeletal muscle. These findings highlight that the link between senescence and inflammation can be disrupted in skeletal muscle.


Assuntos
Envelhecimento/fisiologia , Treino Aeróbico , Inflamação/prevenção & controle , Músculo Esquelético/fisiologia , Resistência Física/fisiologia , Homeostase do Telômero/fisiologia , Idoso , Senescência Celular/genética , Senescência Celular/fisiologia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Humanos , Masculino , Músculo Esquelético/química , Músculo Esquelético/citologia , RNA Mensageiro/análise , Células Satélites de Músculo Esquelético/fisiologia , Células Satélites de Músculo Esquelético/ultraestrutura , Telômero/fisiologia , Telômero/ultraestrutura , Adulto Jovem , beta-Galactosidase/análise
7.
J Sports Sci ; 38(18): 2080-2091, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32530734

RESUMO

Acute and adaptive changes in systemic markers of oxidatively generated nucleic acid modifications (i.e., 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) and 8-oxo-7,8-dihydroguanosine (8-oxoGuo)) as well as inflammatory cytokines (i.e., C-reactive protein, interleukin-6, interleukin-10, and tumour necrosis factor alpha), a liver hormone (i.e., fibroblast growth factor 21 (FGF21)), and bone metabolism markers (sclerostin, osteocalcin, C-terminal telopeptide, and N-terminal propeptide of type 1 procollagen) were investigated following a marathon in 20 study participants. Immediate changes were observed in inflammatory cytokines, FGF21, and bone metabolism markers following the marathon. In contrast, no immediate changes in urinary excretion of 8-oxodG and 8-oxoGuo were evident. Four days after the marathon, decreased urinary excretion of 8-oxodG (-2.9 (95% CI -4.8;-1.1) nmol/24 h, P < 0.01) and 8-oxoGuo (-5.8 (95% CI -10.3;-1.3) nmol/24 h, P = 0.02) was observed. The excretion rate of 8-oxodG remained decreased 7 days after the marathon compared to baseline (-2.3 (95%CI -4.3;-0.4) nmol/24 h, P = 0.02), whereas the excretion rate of 8-oxoGuo was normalized. In conclusion marathon participation immediately induced a considerable inflammatory response, but did not increase excretion rates of oxidatively generated nucleic acid modifications. In fact, a delayed decrease in oxidatively generated nucleic acid modifications was observed suggesting adaptive antioxidative effects following exercise. ABBREVIATIONS: 8-oxodG: 8-oxo-7,8-dihydro-2'-deoxyguanosine; 8-oxoGuo: 8-oxo-7,8-dihydroguanosine; CI: confidence interval; CTX: C-terminal telopeptide of type 1 collagen; DXA: dual-energy X-ray absorptiometry; ELISA: enzyme-linked immunosorbent assay; FGF21: Fibroblast growth factor 21; h: hour; hsCRP: high sensitivity C-reactive protein; IL: interleukin; IQR: interquartile range; MS: mass spectrometry: P1NP: N-terminal propeptide of type 1 procollagen; TNFα: tumour necrosis factor alpha; UPLC: ultra-performance liquid chromatography.


Assuntos
Inflamação/sangue , Inflamação/urina , Estresse Oxidativo , Resistência Física/fisiologia , Corrida/fisiologia , 8-Hidroxi-2'-Desoxiguanosina/urina , Biomarcadores/sangue , Biomarcadores/urina , Remodelação Óssea , Creatinina/urina , Citocinas/sangue , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
8.
PLoS One ; 15(6): e0233796, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32497130

RESUMO

BACKGROUND: Rugby union match demands are complex, requiring the development of multiple physical qualities concurrently. Quantifying the physical qualities of age grade rugby union players is vital for practitioners to support athlete preparation and long-term development. AIM: This systematic review aimed to identify the methods used to quantify the physical qualities of male age grade (≤ Under-20) rugby union players, present the normative values for physical qualities, and compare physical qualities between age grades and positions. METHODS: Electronic databases were systematically reviewed from the earliest record to November 2019 using key words relating to sex, age, sport and physical testing. RESULTS: Forty-two studies evaluated the physical qualities of age grade rugby union players. Seventy-five tests were used to quantify body composition, muscular strength, muscular power, linear speed, change of direction ability, aerobic capacity and anaerobic endurance. Thirty-one studies met the eligibility criteria to present the physical qualities. Physical qualities differentiate between age groups below Under-16, while differences in older age groups (Under-16 to Under-20) are not clear. Positional differences are present with forwards possessing greater height, body mass, body fat percentage and strength while backs are faster and have greater aerobic capacities. CONCLUSIONS: A wide variety of tests are used to assess physical qualities limiting between study comparisons. Although differences in older age grades are unclear, older age groups (Under-19-20) generally performed better in physical tests. Positional differences are associated with match demands where forwards are exposed to less running but a greater number of collisions. Practitioners can use the results from this review to evaluate the physical qualities of age grade rugby union players to enhance training prescription, goal setting and player development. Future research should consider the use of national standardised testing batteries due to the inconsistency in testing methods and small samples limiting the reporting of positional differences.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Teste de Esforço/métodos , Futebol Americano/fisiologia , Força Muscular/fisiologia , Adolescente , Composição Corporal/fisiologia , Tamanho Corporal/fisiologia , Criança , Humanos , Masculino , Resistência Física/fisiologia , Aptidão Física/fisiologia , Corrida/fisiologia , Adulto Jovem
9.
PLoS One ; 15(6): e0233264, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32479554

RESUMO

The dogs' responses to training exercise are seldom monitored using physiological variables, and cardiac autonomic regulation (CAR) is a relevant determinant of endurance-training adaptation. There are studies in the literature establishing that regular exercise could interfere with CAR in dogs, measured by heart rate and vagal-derived indexes of heart-rate-variability (HRV). However, few studies were found using a prescribed training program based on the lactate threshold (LT) to determine HRV by a 24-h Holter analysis. The purpose of this study was to test whether an endurance-training program (ETP) guided individually by LT raises time-domain measures of HRV in healthy Beagle dogs. Twenty dogs were assigned to two groups: control (C) and trained (T). The dogs from group T underwent an incremental exercise test (IET) to determine their LT. Both LT and velocity corresponding to the LT (VLT) was determined by visual inspection. T group performed an eight-week endurance-training program consisting of treadmill runs set to 70-80% of the VLT. Next, dogs from the group T have submitted to IET again. The maximal velocities (Vmax) at which achieved by the trained dogs in both IETs were determined. The group S did not undergo IETs or ETP. HRV was determined by the 24-hour-Holter at rest, before and on the 2°, 4°, 6° and 8° training weeks. To examine the HR impact on HRV, standard HRV variables were normalized to prevailing HR. VLT and Vmax rose in group T, indicating an improvement of dogs' aerobic and anaerobic capacity. The normalized standard HRV indexes were relatively attenuated since these variables had a reduction in the degree of correlation concerning an average HR. The ETP resulted in decreased resting heart rate and increased time-domain indices, highlighting the log-transformed square root of the mean sum of the squared differences between R-R intervals (Ln rMSSD). The lactate-guided endurance-training program could lead to better parasympathetic cardiac modulation in Beagle dogs.


Assuntos
Frequência Cardíaca/fisiologia , Ácido Láctico/metabolismo , Condicionamento Físico Animal/métodos , Animais , Sistema Nervoso Autônomo/fisiologia , Cães , Eletrocardiografia Ambulatorial/métodos , Eletrocardiografia Ambulatorial/veterinária , Treino Aeróbico/métodos , Teste de Esforço , Feminino , Coração/fisiologia , Masculino , Resistência Física/fisiologia , Nervo Vago/fisiologia
10.
Int J Sports Med ; 41(9): 574-581, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32353881

RESUMO

Over recent decades the association between metabolic and gas exchange parameters during exercise has become evident. Different "thresholds" (such as lactate thresholds, critical power, EMG thresholds) and intensity domains appear to be linked to an upper limit of oxygen uptake steady state (V̇O2SS). The aim of this study was to investigate whether MLSS is associated with the upper limit for a V̇O2SS. Forty-five subjects underwent one incremental test and 4-6 30-minute MLSS tests on a cycle ergometer. A three-component model was used to describe V̇O2 response at PMLSS and just above PMLSS+1. To evaluate the results, breath-by-breath V̇O2 and lactate (LA) values were analyzed using the intraclass correlation coefficient (ICC), increasing (k-) values and the Wilcoxon test. According to the calculated k-values of LA and VO2 at PMLSS and PMLSS+1, no significant increase of VO2 occurred during both intensities (PMLSS and PMLSS+1) from minute 10 to minute 30, confirming the existence of a V̇O2SS. Additionally, the ICC of 0.94 confirmed high accordance of the VO2 kinetics at both intensities (PMLSS and PMLSS+1). This study shows that power output at MLSS workload does not represent an accurate cut for an upper limit of V̇O2SS.


Assuntos
Limiar Anaeróbio/fisiologia , Exercício Físico/fisiologia , Ácido Láctico/sangue , Troca Gasosa Pulmonar/fisiologia , Adulto , Teste de Esforço , Feminino , Humanos , Masculino , Resistência Física/fisiologia , Adulto Jovem
11.
Int J Sports Med ; 41(9): 582-588, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32353882

RESUMO

Acute prolonged endurance running has been shown to alter muscle-specific circulating microRNA (miRNA) levels. Here, eighteen participants completed an 8 km run. We assessed the levels of hsa-miR-1-3p, -133a-3p, -133b, and -206 and their correlation with conventional biomarkers following exercise. Compared to before exercise (Pre), 8 km run significantly increased the lactate level immediately after exercise (0 h). Myoglobin (Mb) level increased at 0 h while creatine kinase (CK) level increased 24 h after exercise (24 h). The levels of creatine kinase MB isoenzyme (CK-MB) and cardiac troponin I (cTnI) were all elevated at 24 h and within the normal physiological range; The levels of hsa-miR-1-3p, -133a-3p, -133b significantly increased at 0 h but only hsa-miR-133a-3p still elevated at 24 h. Only hsa-miR-206 level decreased at 24 h; Additionally, the changes of hsa-miR-1-3p and hsa-miR-133a-3p were correlated with Mb at 24 h. These findings suggest that muscle-specific miRNA elevation in plasma is likely physiological and that these miRNA may be used as potential biomarkers for load monitoring in individuals.


Assuntos
MicroRNA Circulante/sangue , Músculo Esquelético/metabolismo , Resistência Física/fisiologia , Corrida/fisiologia , Adaptação Fisiológica , Biomarcadores/sangue , Frequência Cardíaca/fisiologia , Humanos , Ácido Láctico/sangue , Masculino , Músculo Esquelético/lesões , Consumo de Oxigênio/fisiologia , Condicionamento Físico Humano/fisiologia , Mecânica Respiratória/fisiologia , Corrida/lesões , Adulto Jovem
12.
PLoS One ; 15(5): e0226313, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32396576

RESUMO

This descriptive study aimed to explore the physiological factors that determine tolerance to exertion during high-intensity interval effort. Forty-seven young women (15-28 years old) were enrolled: 23 athletes from Taiwan national or national reserve teams and 24 moderately active females. Each participant underwent a maximal incremental INC (modified Bruce protocol) cardiopulmonary exercise test on the first day and high-intensity interval testing (HIIT) on the second day, both performed on a treadmill. The HIIT protocol involved alternation between 1-min effort at 120% of the maximal speed, at the same slope reached at the end of the INC, and 1-min rest until volitional exhaustion. Gas exchange, heart rate (HR), and muscle oxygenation at the right vastus lateralis, measured by near-infrared spectroscopy, were continuously recorded. The number of repetitions completed (Rlim) by each participant was considered the HIIT tolerance index. The results showed a large difference in the Rlim (range, 2.6-12.0 repetitions) among the participants. Stepwise linear regression revealed that the variance in the Rlim within the cohort was related to the recovery rates of oxygen consumption ([Formula: see text]), HR at the second minute after INC, and muscle tissue saturation index at exhaustion (R = 0.644). In addition, age was linearly correlated with Rlim (adjusted R = -0.518, p < 0.0001). In conclusion, the recovery rates for [Formula: see text] and HR after the incremental test, and muscle saturation index at exhaustion, were the major physiological factors related to HIIT performance. These findings provide insights into the role of the recovery phase after maximal INC exercise testing. Future research investigating a combination of INC and HIIT testing to determine training-induced performance improvement is warranted.


Assuntos
Atletas , Teste de Esforço/métodos , Treinamento Intervalado de Alta Intensidade/métodos , Resistência Física/fisiologia , Adolescente , Adulto , Feminino , Frequência Cardíaca/fisiologia , Humanos , Consumo de Oxigênio/fisiologia , Taiwan , Adulto Jovem
13.
J Sports Sci ; 38(15): 1699-1707, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32321385

RESUMO

This study tested the effect of 8-week endurance and resistance training programmes on cardiovascular stress responses, life stress, and coping. Fifty-two untrained but healthy female students were randomised to an 8-week endurance training, an 8-week resistance training, or a wait list control group. Before and after the training intervention, we assessed the groups' cardiorespiratory fitness (VO2max test), self-reported life stress, coping strategies and cardiovascular reactivity to and recovery from a standardised laboratory stressor. Both endurance and resistance training programmes caused physiological adaptation in terms of increased VO2max after the intervention. For stress and coping parameters, participants in the training groups improved cardiovascular recovery from stress and reported having less stress in their everyday life after the intervention than participants in the control group, while the two training groups did not differ from each other. We did not find any significant differences in heart rate reactivity and coping strategies between the study groups. These results partly support that exercise training has stress-reducing benefits regardless of the type of exercise. Both endurance and resistance exercise activities may be effectively used to improve stress regulation competence while having less impact on changing specific coping strategies.


Assuntos
Adaptação Psicológica/fisiologia , Fenômenos Fisiológicos Cardiovasculares , Resistência Física/fisiologia , Treinamento de Resistência/métodos , Estresse Psicológico/fisiopatologia , Estresse Psicológico/terapia , Teste de Esforço , Feminino , Frequência Cardíaca/fisiologia , Humanos , Percepção/fisiologia , Adulto Jovem
14.
J Sports Med Phys Fitness ; 60(7): 1020-1026, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32253893

RESUMO

BACKGROUND: Muscle soreness is also induced during prolonged running such as a full marathon, and muscle soreness and increased damage markers are detected immediately after such a running. We named this muscle soreness, early onset muscle soreness (EOMS). Additionally, lactate dehydrogenase (LDH) level which has some isoenzyme is increased immediately after prolonged exercise. However, it is unclear that EOMS is related to muscle damage markers on prolonged running. This study aimed to determine at which point EOMS, and muscle damage markers are related to EOMS during prolonged running. METHODS: We studied 11 male subjects who habitually perform aerobic exercise. They ran 30 km at 90% of ventilatory threshold intensity. Every 10 km, we estimated perceived muscle soreness, and sampled blood to measure muscle and liver damage, inflammation, and oxidative stress (d-ROM and BAP) markers. RESULTS: Muscle soreness score lower limbs were significantly appeared at 20 km compared to that at 0 km. Serum lactate dehydrogenase (LDH) level increased at 30 km compared to that at 0 km. LDH isoenzymes 3, 4, and 5, and neutrophils significantly increased at 30 km compared to those at 0 km. Serum LDH isoenzyme 5 and change in aspartate aminotransferase significantly increased at 20 km. In addition, there was a significant correlation between the thigh NRS and amount of serum LDH isoenzyme 5 from 0 km to 20 km. d-ROM and BAP increased at 10 km compared to those at 0 km. CONCLUSIONS: EOMS started to occur at 20 km during a 30 km running task. Our data suggest that LDH isoenzyme 5 is a marker of occurrence in EOMS during prolonged running.


Assuntos
Lactato Desidrogenase 5/sangue , Mialgia/diagnóstico , Mialgia/enzimologia , Resistência Física/fisiologia , Corrida/lesões , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Creatina Quinase/sangue , Humanos , Inflamação/sangue , Isoenzimas/sangue , L-Lactato Desidrogenase/sangue , Contagem de Leucócitos , Extremidade Inferior/fisiopatologia , Masculino , Neutrófilos , Estresse Oxidativo , Corrida/fisiologia , Adulto Jovem
15.
PLoS One ; 15(4): e0231643, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32315330

RESUMO

Low-intensity training involving high repetitions is recommended to enhance muscular endurance. Hyperoxic conditions could increase the number of repetitions until exhaustion and thereby improve the results of muscular endurance training. This study aimed to investigate the acute effects of hyperoxia on dynamic muscular endurance, and determine individual factors that may be related to these effects. A single-blinded, counterbalanced crossover design was used. Twenty-five young men performed repetitions of the one-arm preacher curl at 30% of their 1-repetition maximum until exhaustion under hyperoxic and normoxic conditions. The maximum number of repetitions was recorded as an index of muscular endurance. Electromyogram (EMG) and near-infrared spectroscopy parameters were measured in the biceps brachii. The maximum number of repetitions was greater (P < 0.001) under hyperoxic conditions (132 ± 59 repetitions) than under normoxic conditions (114 ± 40 repetitions). The root mean square amplitude of EMG and oxygenated hemoglobin concentration for the last five repetitions under normoxic conditions were greater than those under hyperoxic conditions (P = 0.015 and P = 0.003, respectively). The percent change in the maximum number of repetitions between hyperoxic and normoxic conditions had significant positive correlations with individual maximal oxygen uptake measured using an incremental cycle ergometer test (r = 0.562, 95% confidence intervals [CI] = 0.213-0.783, P = 0.003), but not with muscle strength (τ = -0.124, 95% CI = -0.424-0.170, P = 0.387). The 95% CI for the correlation coefficient between the percent change in the maximum number of repetitions and muscular endurance included 0 (τ = 0.284, 95% CI = -0.003-0.565, P = 0.047); this indicated no significant correlation between the two parameters. The results suggest that hyperoxia can acutely enhance dynamic muscular endurance, with delayed elevation of EMG amplitude due to fatigue, and the effects are associated with individual whole-body endurance capacity.


Assuntos
Hiperóxia/metabolismo , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Resistência Física/fisiologia , Adulto , Eletromiografia , Humanos , Masculino , Contração Muscular/fisiologia , Músculo Esquelético/metabolismo , Oxigênio/metabolismo , Treinamento de Resistência , Levantamento de Peso , Adulto Jovem
16.
Int J Sports Med ; 41(8): 545-551, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32289841

RESUMO

The aim of this study was to determine the influence of body weight or lean body mass-based load on Wingate Anaerobic Test performance in male and female endurance trained individuals. Thirty-one participants (22 male cyclists and triathletes and 9 female triathletes) completed two randomized Wingate Anaerobic Test (body weight and lean body mass loads) in stationary start. There were no significant differences in power outputs variables between loads in any group. However, when comparing specific groups within the sample (e. g. cyclists vs cyclists) medium to large effect sizes were observed for Relative Mean Power Output (ES=0.53), Relative Lowest Power (ES=0.99) and Relative Power Muscle Mass (ES=0.54). Regarding gender differences, male cyclists and triathletes displayed higher relative and absolute power outputs (p<0.001) compared to female triathletes regardless of the protocol used. FI was lower in female triathletes compared to male triathletes and cyclists in body weight (p<0.001) and lean body mass (p<0.01) protocols. Body composition and anthropometric characteristics were similar in male cyclists and triathletes, but there were differences between genders. These results suggest that using either body weight-based or lean body mass-based load can be used interchangeably. However, there may be some practically relevant differences when evaluating this on an individual level.


Assuntos
Índice de Massa Corporal , Peso Corporal , Resistência Física/fisiologia , Esportes/fisiologia , Adulto , Ciclismo/fisiologia , Estudos Cross-Over , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Corrida/fisiologia , Fatores Sexuais , Natação/fisiologia , Adulto Jovem
17.
PLoS One ; 15(4): e0232118, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32343716

RESUMO

This study aimed to investigate differences in anthropometric characteristics and physical capacities (1) between under (U) 17, 19, and 21 years old elite junior soccer players, and also (2) between starting and nonstarting players within each age group. Ninety-two male elite German junior field players were tested for height, mass, fat, and fat-free mass as well as aerobic endurance, squat (SJ) and counter movement jump (CMJ), linear sprint, core strength-endurance, and one repetition maximum (1RM) bench press performance. According to their age and competitive match playing times, the players were divided into the mentioned different groups. Magnitude-based inferences and effect sizes (ES) were computed for statistical analyses. The fat-free mass, SJ and CMJ, 1RM bench press, and linear sprinting performances increased likely to most likely from U17 to U21 players (ES: moderate to large), whereas the body fat, core strength-endurance, and aerobic endurance performances remain constant. The fat-free mass, 1RM bench press, and linear sprinting performances were likely to most likely higher in U21 starting compared to nonstarting players (ES: moderate to large). Our study shows that contrary to endurance, power associated capacities differ between different aged and starting-nonstarting elite junior soccer players. This outcome should be considered for training, testing, and talent selection procedures in elite junior soccer players.


Assuntos
Resistência Física/fisiologia , Treinamento de Resistência/métodos , Adolescente , Antropometria , Desempenho Atlético/fisiologia , Alemanha , Humanos , Masculino , Estudos Retrospectivos , Futebol , Adulto Jovem
18.
Artigo em Inglês | MEDLINE | ID: mdl-32244582

RESUMO

The present case study analyzed performance, pacing, and potential predictors in a self-paced world record attempt of a professional triathlete to finish 40 Ironman-distance triathlons within 40 days. Split times (i.e., swimming, cycling, running) and overall times, body weight, daily highest temperature, wind speed, energy expenditure, mean heart rate, and sleeping time were recorded. Non-linear regressions were applied to investigate changes in split and overall times across days. Multivariate regression analyses were performed to test which variables showed the greatest influence on the dependent variables cycling, running and overall time. The athlete completed the 40×Ironman distances in a total time of 444:22 h:min. He spent 50:26 h:min in swimming, 245:37 h:min in cycling, 137:17 h:min in running and 11:02 h:min in transition times. Swimming and cycling times became slower across days, whereas running times got faster until the 20th day and, thereafter, became slower until the 40th day. Overall times got slower until the 15th day, became faster to 31st, and started then to get slower until the end. Wind speed, previous day's race time and average heart race during cycling were significant independent variables influencing cycling time. Body weight and average heart rate during running were significant independent variables influencing running performance. Cycling performance, running performance, and body weight were significant independent variables influencing overall time. In summary, running time was influenced by body weight, cycling by wind speed, and overall time by both running and cycling performances.


Assuntos
Atletas , Desempenho Atlético , Exercício Físico , Adulto , Desempenho Atlético/fisiologia , Ciclismo , Exercício Físico/fisiologia , Humanos , Masculino , Resistência Física/fisiologia , Corrida , Natação
19.
Braz J Med Biol Res ; 53(4): e9200, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32267309

RESUMO

The consumption of alcoholic beverages influences carbohydrate and lipid metabolism, although it is not yet clear whether metabolism during physical exercise at different intensities is also affected. This was the objective of the present study. Eight young and healthy volunteers performed a treadmill test to identify the running speed corresponding to a lactate concentration of 4 mM (S4mM). At least 48 h later, they were subjected to two experimental trials (non-alcohol or alcohol) in which they performed two 1-km running sessions at the following intensities: 1) S4mM; 2) 15% above S4mM. In both trials, blood lactate, triglycerides, and glucose concentrations were measured before and after exercise. The acute alcohol intake increased triglycerides, but not lactate concentration under resting conditions. Interestingly, alcohol intake enhanced the exercise-induced increase in lactate concentration at the two intensities: S4mM (non-alcohol: 4.2±0.3 mM vs alcohol: 4.8±0.9 mM; P=0.003) and 15% above S4mM trial (P=0.004). When volunteers ingested alcohol, triglycerides concentration remained increased after treadmill running (e.g., at S4mM - at rest; non-alcohol: 0.2±0.5 mM vs alcohol: 1.3±1.3 mM; P=0.048). In contrast, glucose concentration was not modified by either alcohol intake, exercise, or their combination. We concluded that an acute alcohol intake changed lactate and lipid metabolism without affecting blood glucose concentration. In addition, the increase in lactate concentration caused by alcohol was specifically observed when individuals exercised, whereas augmented triglycerides concentration was already observed before exercise and was sustained thereafter.


Assuntos
Consumo de Bebidas Alcoólicas/sangue , Bebidas Alcoólicas/análise , Glicemia/metabolismo , Etanol/metabolismo , Ácido Láctico/sangue , Resistência Física/efeitos dos fármacos , Adulto , Desempenho Atlético/fisiologia , Glicemia/análise , Teste de Esforço , Humanos , Masculino , Resistência Física/fisiologia , Triglicerídeos/sangue , Adulto Jovem
20.
Int J Sports Med ; 41(8): 539-544, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32289842

RESUMO

The purpose was to determine the physiological correlates to cycling performance within a competitive paratriathlon. Five wheelchair user and ten ambulant paratriathletes undertook laboratory-based testing to determine their: peak rate of oxygen uptake; blood lactate- and ventilatory-derived physiological thresholds; and, their maximal aerobic power. These variables were subsequently expressed in absolute (l∙min -1 or W), relative (ml∙kg-1∙min -1 or W∙kg -1) and scaled relative (or ml∙kg - 0.82 ∙min -1, ml∙kg - 0.32 ∙min -1 or W∙kg -0.32) terms. All athletes undertook a paratriathlon race with 20 km cycle. Pearson's correlation test and linear regression analyses were produced between laboratory-derived variables and cycle performance to generate correlation coefficients (r), standard error of estimates and 95% confidence intervals. For wheelchair users, performance was most strongly correlated to relative aerobic lactate threshold (W∙kg -1) (r=-0.99; confidence intervals: -0.99 to -0.99; standard error of estimate=22 s). For ambulant paratriathletes, the greatest correlation was with maximal aerobic power (W∙kg -0.32) (r=-0.91; -0.99 to -0.69; standard error of estimate=88 s). Race-category-specificity exits regarding physiological correlates to cycling performance in a paratriathlon race with further differences between optimal scaling factors between paratriathletes. This suggests aerobic lactate threshold and maximal aerobic power are the pertinent variables to infer cycling performance for wheelchair users and ambulant paratriathletes, respectively.


Assuntos
Ciclismo/fisiologia , Comportamento Competitivo/fisiologia , Resistência Física/fisiologia , Esportes para Pessoas com Deficiência/fisiologia , Adulto , Limiar Anaeróbio/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Ácido Láctico/sangue , Masculino , Consumo de Oxigênio/fisiologia
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