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1.
PLoS One ; 15(11): e0242439, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33186393

RESUMO

Sprint-interval training (SIT) is efficient at improving maximal aerobic capacity and anaerobic fitness at sea-level and may be a feasible training strategy at altitude. Here, it was evaluated if SIT intensity can be maintained in mild to moderate hypoxia. It was hypothesized that 6 x 30 s Wingate sprint performance with 2 min active rest between sprints can be performed in hypoxic conditions corresponding to ~3,000 m of altitude without reducing mean power output (MPO). In a single-blinded, randomized crossover design, ten highly-trained male endurance athletes with a maximal oxygen uptake ([Formula: see text]O2max) of 68 ± 5 mL O2 × min-1 × kg-1 completed 6 x 30 s all-out Wingate cycling sprints separated by two-minute active recovery on four separate days in a hypobaric chamber. The ambient pressure within the chamber on each experimental day was 772 mmHg (~0 m), 679 mmHg (~915 m), 585 mmHg (~ 2,150 m), and 522 mmHg (~3,050 m), respectively. MPO was not different at sea-level and up to ~2,150 m (~1% and ~3% non-significant decrements at ~915 and ~2,150 m, respectively), whereas MPO was ~5% lower (P<0.05) at ~3,050 m. Temporal differences between altitudes was not different for peak power output (PPO), despite a main effect of altitude. In conclusion, repeated Wingate exercise can be completed by highly-trained athletes at altitudes up to ~2,150 m without compromising MPO or PPO. In contrast, MPO was compromised in hypobaric hypoxia corresponding to ~3,050 m. Thus, SIT may be an efficient strategy for athletes sojourning to moderate altitude and aiming to maintain training quality.


Assuntos
Tolerância ao Exercício/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Consumo de Oxigênio/fisiologia , Adulto , Altitude , Atletas , Estudos Cross-Over , Exercício Físico/fisiologia , Humanos , Hipóxia/metabolismo , Hipóxia/fisiopatologia , Masculino , Condicionamento Físico Humano/métodos , Resistência Física/fisiologia , Aptidão Física/fisiologia , Distribuição Aleatória , Corrida/fisiologia
2.
BMJ ; 371: m3485, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028588

RESUMO

OBJECTIVE: To evaluate the effect of five years of supervised exercise training compared with recommendations for physical activity on mortality in older adults (70-77 years). DESIGN: Randomised controlled trial. SETTING: General population of older adults in Trondheim, Norway. PARTICIPANTS: 1567 of 6966 individuals born between 1936 and 1942. INTERVENTION: Participants were randomised to two sessions weekly of high intensity interval training at about 90% of peak heart rate (HIIT, n=400), moderate intensity continuous training at about 70% of peak heart rate (MICT, n=387), or to follow the national guidelines for physical activity (n=780; control group); all for five years. MAIN OUTCOME MEASURE: All cause mortality. An exploratory hypothesis was that HIIT lowers mortality more than MICT. RESULTS: Mean age of the 1567 participants (790 women) was 72.8 (SD 2.1) years. Overall, 87.5% of participants reported to have overall good health, with 80% reporting medium or high physical activity levels at baseline. All cause mortality did not differ between the control group and combined MICT and HIIT group. When MICT and HIIT were analysed separately, with the control group as reference (observed mortality of 4.7%), an absolute risk reduction of 1.7 percentage points was observed after HIIT (hazard ratio 0.63, 95% confidence interval 0.33 to 1.20) and an absolute increased risk of 1.2 percentage points after MICT (1.24, 0.73 to 2.10). When HIIT was compared with MICT as reference group an absolute risk reduction of 2.9 percentage points was observed (0.51, 0.25 to 1.02) for all cause mortality. Control participants chose to perform more of their physical activity as HIIT than the physical activity undertaken by participants in the MICT group. This meant that the controls achieved an exercise dose at an intensity between the MICT and HIIT groups. CONCLUSION: This study suggests that combined MICT and HIIT has no effect on all cause mortality compared with recommended physical activity levels. However, we observed a lower all cause mortality trend after HIIT compared with controls and MICT. TRIAL REGISTRATION: ClinicalTrials.gov NCT01666340.


Assuntos
Envelhecimento , Exercício Físico , Frequência Cardíaca/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Desempenho Físico Funcional , Idoso , Envelhecimento/fisiologia , Envelhecimento/psicologia , Causas de Morte , Exercício Físico/fisiologia , Exercício Físico/psicologia , Feminino , Humanos , Masculino , Mortalidade , Avaliação de Resultados em Cuidados de Saúde , Aptidão Física , Comportamento de Redução do Risco
3.
J Sports Sci Med ; 19(3): 508-516, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32874103

RESUMO

The aim of this investigation was to compare the changes in endurance running performance and physiological variables after a four-week period of high intensity interval training (HIIT) in either running or cycling in female athletes. Fourteen recreational female runners (age = 42 10 yr, height = 1.67 0.06 m, body mass = 61.6 10.4 kg, body mass index (BMI) = 22.2 3.4 kg.m-2) were randomly allocated to one of two HIIT training groups: running (HIITrun) or cycling (HIITbike). Each group performed two HIIT sessions per week for 4 weeks, which consisted of 6 x 2 min at 95% of maximal heart rate (HRmax) and 4 x 1 min all out efforts. Maximal oxygen consumption (VO2max) in treadmill running increased significantly after the HIITrun (p < 0.01, ES = 0.6) but remained unchanged in HIITbike. However, HIITbike improved average velocity in a 10 km running time trial (TTrun) (p < 0.05, ES = -0.4), whereas, no changes were found for the HIITrun group. Analysing the first and last HIIT sessions, for HIITrun only the average rate of perceived exertion (RPEav) increased significantly, whereas, performance variables such as average heart rate (HRav) and average pace (paceav) remained unchanged. HIITbike enhanced significantly the average speed of HIIT sets (speedav) and the peak power output (PPO) of the session, as well as, the RPEav and delayed onset muscle soreness immediately after HIIT session (DOMSpost) were increased significantly. A regime of HIIT in cycling may evoke increases in female recreational runners' power, which may be related with improvements in a 10 km TTrun independent of changes in aerobic capacity. This may be advantageous in order to avoid overuse running related injuries.


Assuntos
Ciclismo/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Resistência Física/fisiologia , Corrida/fisiologia , Adulto , Creatina Quinase/sangue , Feminino , Frequência Cardíaca , Humanos , Ácido Láctico/sangue , Pessoa de Meia-Idade , Fadiga Muscular/fisiologia , Mialgia/metabolismo , Mialgia/fisiopatologia , Consumo de Oxigênio , Percepção/fisiologia , Esforço Físico/fisiologia
4.
J Sports Med Phys Fitness ; 60(8): 1065-1071, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32955832

RESUMO

BACKGROUND: It is well established that acute exercise improves cognitive function. However, less is known about the effects of exercise on motor skill acquisition. Therefore, this study investigated the effects of acute high-intensity interval training (HIIT) on motor skill acquisition. METHODS: Sixty individuals (27 males, 33 females) between 18 and 40 years of age participated in two testing sessions separated by one week. During visit 1, participants performed one block of a continuous tracking, force control task to establish baseline ability. Participants were then randomized to either an aerobic-only HIIT group (HIIT-A), an aerobic/resistance HIIT group (HIIT-AR), or a resting control group. Both exercise groups performed a 20-minute, digital versatile disc (DVD)-delivered HIIT exercise protocol during visit 2. Following exercise or rest, all participants performed five blocks of the same force control task to assess skill acquisition. RESULTS: On visit 2, the HIIT-A group had a significantly lower total performance error (E) compared to the control group (P<0.05). Both exercise groups (HIIT-A and HIIT-AR) had a significantly lower peak amplitude error (PE) following exercise compared to the control group (P<0.05). No significant group differences were observed for temporal error (TE). Additionally, no significant differences were observed between the exercise groups (P>0.05). CONCLUSIONS: These findings suggest that acute HIIT-A improves motor skill acquisition compared to rest. Furthermore, improvements in acquisition appeared to be a result of improved spatial accuracy. Therefore, performing HIIT-A prior to practicing a motor task may help reduce total error during the motor skill acquisition phase.


Assuntos
Treinamento Intervalado de Alta Intensidade/métodos , Destreza Motora/fisiologia , Adolescente , Adulto , Cognição/fisiologia , Exercício Físico/psicologia , Feminino , Treinamento Intervalado de Alta Intensidade/psicologia , Humanos , Estudos Longitudinais , Masculino , Adulto Jovem
5.
PLoS One ; 15(8): e0237887, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32817652

RESUMO

The effects of High-Intensity Functional Training (HIFT) on body composition and the relationship of the latter with performance are not well defined. In this work we investigated, by means of Dual-energy X-ray Absorptiometry, the relative proportions of fat-, lean soft tissue-, and mineral mass in CrossFit® (CF, a popular mode of HIFT) participants (n = 24; age, 28.2 ± 3.39 y; BMI, 25.3 ± 2.04 kg/m2) with at least 1 year of CF training experience and weekly amount of training > 10 h/w (n = 13; Higher Training, HT) or < 10 h/w (n = 11; Lower Training, LT) as well as age- matched and BMI-matched physically active controls (CHT, CLT). Performance was assessed in the "Fran" workout. Data were analyzed by one-way or repeated measures ANOVA where needed. Association between variables was assessed with the Pearson's correlation coefficient r. Partial correlation was used where needed. Results showed that HT performed better than LT in the "Fran" (P < 0.001) and they had higher whole-body bone mineral density (P = 0.026) and higher lean soft mass (P = 0.002), and borderline lower percent fat mass (P = 0.050). The main difference between CF participants (HT, LT) and their respective controls (CHT, CLT) was a lower adiposity in the former. In CF participants, performance positively correlated with appendicular lean soft tissue mass (P = 0.030). It can be concluded that, in CF participants, a higher amount of weekly training improves most notably lean body mass and increases performance in association with increased skeletal muscle mass. CF participation is especially effective in reducing fat mass vs. age- and BMI-matched physically active controls.


Assuntos
Composição Corporal/fisiologia , Exercício Físico/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Músculo Esquelético/fisiologia , Absorciometria de Fóton , Tecido Adiposo , Adiposidade/fisiologia , Adulto , Braço/fisiologia , Glicemia , Índice de Massa Corporal , Peso Corporal , Densidade Óssea , Capilares/fisiologia , Humanos , Masculino , Músculo Esquelético/anatomia & histologia , Adulto Jovem
6.
Health Qual Life Outcomes ; 18(1): 283, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807179

RESUMO

BACKGROUND: Studies on the effect of high-intensity interval training (HIT) compared with moderate intensity continuous training (MICT) on health-related quality of life (HRQoL) after heart transplantation (HTx) is scarce. No available studies among de novo HTx recipients exists. This study aimed to investigate the effect of HIT vs. MICT on HRQoL in de novo recipients. METHODS: The HITTS study randomized eighty-one de novo HTx recipients to receive either HIT or MICT (1:1). The HIT intervention were performed with 2-4 interval bouts with an intensity of 85-95% of maximal effort. The MICT group exercised at an intensity of 60-80% of their maximal effort with a duration of 25 min. HRQoL was assessed by the Short Form-36 version 2 (SF-36v2) and the Hospital Anxiety and Depression Scale, mean 11 weeks after surgery and after a nine months' intervention. The participants recorded their subjective effect of the interventions on their general health and well-being on a numeric visual analogue scale. Clinical examinations and physical tests were performed. Differences between groups were investigated with independent Student t-tests and with Mann-Whitney U tests where appropriate. Within-group differences were analyzed with Paired-Sample t-tests and Wilcoxon Signed Rank tests. Correlations between SF-36 scores and VO2peak were examined with Pearson's correlations. RESULTS: Seventy-eight participants completed the intervention. Both exercise modes were associated with improved exercise capacity on the physical function scores of HRQoL. Mental health scores remained unchanged. No differences in the change in HRQoL between the groups occurred except for Role Emotional subscale with a larger increase in the HIT arm. Better self-reported physical function was associated with higher VO2peak and muscle strength. CONCLUSION: HIT and MICT resulted in similar mean changes in HRQoL the first year after HTx. Both groups experienced significant improvements in the physical SF-36v2. TRIAL REGISTRATION: ClinicalTrials.gov number: NCT01796379 Registered 18 February 2013.


Assuntos
Transplante de Coração/reabilitação , Treinamento Intervalado de Alta Intensidade/métodos , Qualidade de Vida , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular , Autorrelato , Transplantados/psicologia
7.
Medicine (Baltimore) ; 99(27): e21062, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32629734

RESUMO

BACKGROUND: The benefits of high-intensity interval training (HIIT) are well-known, there is insufficient evidence about the effects of HIIT on heart failure with preserved ejection fraction (HFpEF). METHOD: Multiple databases include MEDLINE, PubMed, EMBASE, CINAHL, Web of Science, PEDro, Cochrane Library, and Google Scholar are used to search for randomized controlled trials investigating the effects of HIIT on HFpEF. All related articles published with the English language with no time limitation will be included. Two reviews independently conducted the selection, data extraction, and quality assessment. The primary outcome is exercise capacity. The secondary outcomes include quality of life (QoL), blood pressure (BP), ventricular function, and left ventricular diastolic function, symptom improvement, endothelial function, and arterial stiffness. Data analysis is performed with Review Manager Software (Version 5.3). RESULT: This systematic review and meta-analysis aim to evaluate the efficacy of HIIT on HFpEF, its outcome will provide reliable evidence for future studies. CONCLUSION: The findings of this study will be published in a related peer-reviewed journal. REGISTRATION NUMBER: INPLASY202050097.


Assuntos
Insuficiência Cardíaca/reabilitação , Treinamento Intervalado de Alta Intensidade/métodos , Volume Sistólico/fisiologia , Pressão Sanguínea/fisiologia , Diástole/fisiologia , Endotélio Vascular/fisiologia , Estudos de Avaliação como Assunto , Tolerância ao Exercício/fisiologia , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/psicologia , Humanos , Qualidade de Vida/psicologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Rigidez Vascular/fisiologia , Função Ventricular Esquerda/fisiologia
8.
Sci Rep ; 10(1): 11089, 2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32632177

RESUMO

Mitochondria supply intracellular energy requirements during exercise. Specific mitochondrial haplogroups and mitochondrial genetic variants have been associated with athletic performance, and exercise responses. However, these associations were discovered using underpowered, candidate gene approaches, and consequently have not been replicated. Here, we used whole-mitochondrial genome sequencing, in conjunction with high-throughput genotyping arrays, to discover novel genetic variants associated with exercise responses in the Gene SMART (Skeletal Muscle Adaptive Response to Training) cohort (n = 62 completed). We performed a Principal Component Analysis of cohort aerobic fitness measures to build composite traits and test for variants associated with exercise outcomes. None of the mitochondrial genetic variants but eight nuclear encoded variants in seven separate genes were found to be associated with exercise responses (FDR < 0.05) (rs11061368: DIABLO, rs113400963: FAM185A, rs6062129 and rs6121949: MTG2, rs7231304: AFG3L2, rs2041840: NDUFAF7, rs7085433: TIMM23, rs1063271: SPTLC2). Additionally, we outline potential mechanisms by which these variants may be contributing to exercise phenotypes. Our data suggest novel nuclear-encoded SNPs and mitochondrial pathways associated with exercise response phenotypes. Future studies should focus on validating these variants across different cohorts and ethnicities.


Assuntos
Desempenho Atlético/estatística & dados numéricos , Núcleo Celular/genética , DNA Mitocondrial/genética , Exercício Físico , Treinamento Intervalado de Alta Intensidade/métodos , Mitocôndrias/genética , Polimorfismo de Nucleotídeo Único , Adulto , Estudos de Coortes , Humanos
9.
Arch Phys Med Rehabil ; 101(11): 1865-1876, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32585169

RESUMO

OBJECTIVE: To compare the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) combined with strengthening and stretching exercises in patients with fibromyalgia. DESIGN: Interventional, single-blind, randomized controlled trial. SETTING: Outpatient rehabilitation center. PARTICIPANTS: Women with fibromyalgia (N=60) were randomized to HIIT, MICT, and control groups. INTERVENTIONS: HIIT included a 5-minute warm-up at 50% of peak heart rate and 4 cycles of 4 minutes at 80%-95% of peak heart rate followed by 3-minute recovery intervals at 70% of peak heart rate. MICT consisted of 45 minutes at 65%-70% of peak heart rate. Each aerobic training session was followed by standardized strengthening and stretching exercises. The programs performed using cycle ergometers for 5 sessions per week for 6 weeks. The control group did not participate in any supervised exercise sessions. MAIN OUTCOME MEASURES: The primary outcome measure was the Fibromyalgia Impact Questionnaire (FIQ). The secondary outcome measures were visual analog scale for pain, Short Form-36 Health Survey (SF-36), cardiopulmonary exercise test (CPET), and body composition parameters. RESULTS: Fifty-five participants completed the study. There was no significant difference in FIQ between HIIT vs MICT (1.03; 95% CI, -9.67 to 11.75) after treatment. Group-time interactions were significant for the FIQ between interventions and control (HIIT vs control, -16.20; 95% CI, -27.23 to -5.13 and MICT vs control, -17.24; 95% CI, -28.27 to -6.22) (all P<.001). There were significant group-time interactions for the pain, SF-36, and CPET parameters between treatments and control (all P<.05). Body weight, fat percentage, fat mass, and body mass index improved significantly (all P<.05) only in the MICT group after treatment. CONCLUSIONS: The HIIT plus strengthening and stretching exercises and MICT plus strengthening and stretching exercises interventions showed significant improvements for the effect of fibromyalgia, pain degree, functional capacity, and quality of life compared with the control group. HIIT was not superior to MICT. Furthermore, body composition parameters were improved significantly only for the MICT group.


Assuntos
Terapia por Exercício/métodos , Fibromialgia/reabilitação , Treinamento Intervalado de Alta Intensidade/métodos , Adulto , Composição Corporal , Índice de Massa Corporal , Aptidão Cardiorrespiratória , Teste de Esforço , Feminino , Fibromialgia/fisiopatologia , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Desempenho Físico Funcional , Projetos Piloto , Estudos Prospectivos , Qualidade de Vida , Método Simples-Cego , Resultado do Tratamento
10.
J Acquir Immune Defic Syndr ; 84(3): 285-289, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32530906

RESUMO

BACKGROUND: Low cardiorespiratory fitness (CRF) is usually observed in people living with HIV. The effect of a low-volume high-intensity interval training (LV-HIIT) on CRF in HIV+ and HIV- Hispanic women was evaluated in this study. SETTING: A nonrandomized clinical trial with pre-test and post-test using a LV-HIIT intervention was conducted in the AIDS Clinical Trials Unit and the Puerto Rico Clinical and Translational Research Consortium at the University of Puerto Rico Medical Sciences Campus. METHODS: Twenty-nine HIV+ and 13 HIV- Hispanic women recruited from community-based programs and clinics, and able to engage in daily physical activities, volunteered to participate. Of these, 20 HIV+ (69%) and 11 HIV- (85%) completed the study and were included in the analyses. LV-HIIT consisted of 6-week, 3 d/wk, 8-10 high-intensity and low-intensity intervals on a cycle ergometer at 80%-90% of heart rate reserve. Main outcome measures were CRF (defined as VO2peak), peak workload, and time to peak exercise. RESULTS: Average peak workload and time to peak exercise increased after training (P < 0.05) in both groups. However, average CRF was significantly higher after training only in the HIV- group. Gains in CRF were observed in 100% of HIV- and 50% of HIV+ women. This was not influenced by exercise testing, habitual physical activity, or anthropometric variables. CONCLUSIONS: Given the lack of change in CRF observed in the HIV+ group after LV-HIIT intervention, it is important to focus on variations that may occur within groups.


Assuntos
Exercício Físico , Infecções por HIV , Treinamento Intervalado de Alta Intensidade/métodos , Adulto , Antropometria , Aptidão Cardiorrespiratória , Feminino , Infecções por HIV/fisiopatologia , Hispano-Americanos , Humanos , Ensaios Clínicos Controlados não Aleatórios como Assunto , Consumo de Oxigênio , Porto Rico
11.
Apunts, Med. esport (Internet) ; 55(206): 53-61, abr.-jun. 2020. graf, tab
Artigo em Inglês | IBECS | ID: ibc-191744

RESUMO

This study examines the effects of two strength training (ST) programs, one based on mean propulsive velocity (MPV) and another under the traditional method, the % one-repetition maximum (1RM), on neuromuscular performance and muscle composition in girls who play soccer. Fifty players with an average age of 13.6 ± 1.2 years participated in the study and were randomly assigned into three groups: a maximal execution velocity training group (VG, n = 15), a maximal strength group (RMG, n = 13), and a control group (CG, n = 18). The study was developed for a period of twelve weeks during regular team training to prepare for the season. The VG and RMG groups performed additional strength or muscle power training three times a week, including movements of full squat and pedaling on a cycle ergometer. The two types of training groups and the control group exhibited significant gains. However, the greatest increases were achieved with VG training, with significant increases (p < 0.000) in maximal strength, (p < 0.000) squat power, (p < 0.000) velocity over 30 m, (p < 0.000) cycle ergometer power, and (p < 0.008) lower limb muscle mass. Statistically significant differences were observed between VG and RMG in countermovement jump (CMJ) (p < 0.008) and squat power (p < 0.01) tests, between VG and CG in CMJ (p < 0.01), squat power (p < 0.000), and maximal squat strength (p < 0.000), and between RMG and CG in maximal squat strength (p < 0.000) only. These findings might indicate that high-velocity ST can be performed simultaneously with regular training to improve the explosive actions of soccer players


No disponible


Assuntos
Humanos , Feminino , Criança , Adolescente , Desempenho Atlético/fisiologia , Futebol/fisiologia , Força Muscular/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Junção Neuromuscular/fisiologia , Análise de Variância , Treinamento de Resistência/métodos
12.
Nutr. hosp ; 37(3): 514-523, mayo-jun. 2020. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-193859

RESUMO

INTRODUCCIÓN: se evidencia un aumento cada vez mayor de la preocupación debido a valores alarmantes en condición física y composición corporal, que sitúan a los escolares en unos parámetros de riesgo en lo relativo a la salud física. Numerosas investigaciones relacionan la actividad física con la mejora en la condición física y la composición corporal. OBJETIVO: analizar los efectos de un programa de ejercicio interválico de intensidad moderada-vigorosa sobre indicadores de condición física (fuerza isométrica manual en ambas manos, fuerza explosiva del tren inferior, velocidad-agilidad y capacidad aeróbica) y de composición corporal (índice de masa corporal, % de grasa corporal, perímetro de cintura e índice cintura/altura), referentes todos ellos para la salud en escolares de 11 y 12 años. MÉTODOS: se desarrolla una intervención en la que participó un grupo experimental y otro control con 28 escolares cada uno de ellos. Transcurrió a lo largo de 7 semanas, con sesiones de 30 minutos totales antes del inicio de la actividad académica, 3 días por semana. Se realizaron diferentes juegos interválicos, con una intensidad moderada-vigorosa (70-80 % de la frecuencia cardíaca máxima). El registro en condición física y composición corporal se realizó a través de la batería ALPHA. RESULTADOS: mejoras significativas en fuerza isométrica con ambas manos y una reducción significativa del perímetro de cintura e índice cintura/altura. CONCLUSIÓN: los resultados muestran mejoras significativas en indicadores de condición física y composición corporal; sin embargo, se precisa de una intervención de mayor duración para conocer si las otras mejoras logradas en los indicadores analizados consiguen ser significativas con el transcurso del tiempo


INTRODUCTION: there is growing evidence of concern for values in terms of physical condition and body composition that place school children being at risk in physical health. Numerous investigations relate physical activity with improvement in physical condition and body composition. OBJECTIVE: to analyze the effects of a sub-maximal intensity interval exercise program on physical condition (upper body isometric strength in both hands, lower body explosive strength, velocity-agility and cardiorespiratory fitness) and body composition (body mass index, % of body fat, waist circumference and waist/height index), all of them related to health, in schoolchildren of 11 and 12 years. METHODS: an intervention was developed in which an experimental group participated and another control group with 28 schoolchildren each. The study developped over 8 weeks, with sessions of total 30 minutes before the start of the academic activity 3 days per week. Different intervallic games were made with motor, cognitive and coordination challenges; with a moderate-vigorous intensity (70 %-80 % of maximum heart rate). The registration in physical condition and body composition was made through the ALPHA Battery. RESULTS: significant improvements in isometric strength in both hands and a reduction in waist circumference and waist/height were found. CONCLUSIONS: the results show significant improvements in indicators of fitness and fatness, however, it requires a long-term intervention to know if the other improvements achieved in the analyzed indicators are significant over time


Assuntos
Humanos , Masculino , Criança , Composição Corporal/fisiologia , Valor Nutritivo , Treinamento Intervalado de Alta Intensidade/métodos , Atividade Motora/fisiologia , Índice de Massa Corporal , Relação Cintura-Quadril/métodos
13.
Obesity (Silver Spring) ; 28(7): 1245-1253, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32475048

RESUMO

OBJECTIVE: This study aimed to investigate the effect of exercise intensity on visceral adipose tissue (VAT) and liver fat reduction in patients with coronary artery disease (CAD) over 3 months and the maintenance of improvements over 12 months. METHODS: Forty-two participants with CAD were randomized to three sessions/week of either 4 × 4-minute high-intensity interval training (HIIT) or 40 minutes of usual care moderate-intensity continuous training (MICT) for a 4-week supervised cardiac rehabilitation program, followed by three home-based sessions/week for 11 months. Liver fat (as intrahepatic lipid) and VAT were measured via magnetic resonance techniques. Data are mean change (95% CI). RESULTS: HIIT and MICT significantly reduced VAT over 3 months (-350 [-548 to -153] cm3 vs. -456 [-634 to -278] cm3 ; time × group effect: P = 0.421), with further improvement over 12 months (-545 [-818 to -271] cm3 vs. -521 [-784 to -258] cm3 ; time × group effect: P = 0.577) and no differences between groups. Both groups improved liver fat over 3 months, with HIIT tending to show greater reduction than MICT (-2.8% [-4.0% to -1.6%] vs. -1.4% [-2.4% to -0.4%]; time × group effect: P = 0.077). After 12 months, improvements were maintained to a similar degree. Higher exercise intensity predicted liver fat reduction (ß = -0.3 [-0.7 to 0.0]; P = 0.042). CONCLUSIONS: HIIT and MICT reduced VAT over 3 and 12 months. For liver fat, HIIT tended to provide a slightly greater reduction compared with MICT. These findings support HIIT as a beneficial adjunct or alternative to MICT for reducing visceral and liver fat in patients with CAD.


Assuntos
Tecido Adiposo/metabolismo , Reabilitação Cardíaca/métodos , Doença da Artéria Coronariana/terapia , Treinamento Intervalado de Alta Intensidade/métodos , Gordura Intra-Abdominal/patologia , Fígado/metabolismo , Adiposidade/fisiologia , Idoso , Composição Corporal/fisiologia , Feminino , Humanos , Gordura Intra-Abdominal/metabolismo , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Resultado do Tratamento
14.
Int J Sports Physiol Perform ; 15(6): 767-776, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32502972

RESUMO

CONTEXT: Combat sports are composed of high-intensity actions (eg, attacks, defensive actions, and counterattacks in both grappling and striking situations depending on the specific sport) interspersed with low-intensity actions (eg, displacement without contact, stepping) or pauses (eg, referee stoppages), characterizing an intermittent activity. Therefore, high-intensity interval training (HIIT) is at the essence of combat-sport-specific training and is used as complementary training, as well. HIIT prescription can be improved by using intensity parameters derived from combat-sport-specific tests. Specifically, the assessment of physiological indexes (intensity associated with the maximal blood lactate steady state, maximal oxygen consumption, and maximal sprint) or of time-motion variables (high-intensity actions, low-intensity actions, and effort:pause ratio) is a key element for a better HIIT prescription because these parameters provide an individualization of the training loads imposed on these athletes. PURPOSE: To present a proposal for HIIT prescription for combat-sport athletes, exemplifying with different HIIT protocols (HIIT short intervals, HIIT long intervals, repeated-sprint training, and sprint interval training) using combat-sport-specific actions and the parameters for the individualization of these protocols. CONCLUSIONS: The use of combat-sport-specific tests is likely to improve HIIT prescription, allowing coaches and strength and conditioning professionals to elaborate HIIT short intervals, HIIT long intervals, repeated-sprint training, and sprint interval training protocols using combat-sport actions, providing more specificity and individualization for the training sessions.


Assuntos
Desempenho Atlético/fisiologia , Comportamento Competitivo/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Tomada de Decisões , Humanos , Ácido Láctico/sangue , Consumo de Oxigênio/fisiologia
15.
Gene ; 754: 144850, 2020 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-32505844

RESUMO

Obesity is associated with germ cell apoptosis, spermatogenesis arrest, and testicular endocrine suppression. The aim of the present study was to investigate the crosstalk between germ cell apoptosis and cell cycle machinery in sedentary and obese rats after moderate-intensity continuous (MICT), high-intensity continuous (HICT) and High-intensity interval (HIIT) exercise trainings. Male Wistar rats (n = 30) were randomly divided into 5 groups; the control, sedentary high-fat diet (HFD)-received (HFD-sole), MICT, HICT and HIIT-induced HFD-received groups. The serum levels of LDL-C, HDL-C, triglyceride, and testosterone, mRNA and protein levels of Cyclin D1, Cdk4, p21, apoptotic cell number/mm2 of testicular tissue and testicular DNA fragmentation ratio were investigated. The obese animals in HFD-sole group represented a significant (p < 0.05) reduction in serum HDL-C and testosterone levels, Cyclin D1, Cdk4 expressions, and exhibited a remarkable (p < 0.05) increment in LDL-C, triglyceride, p21 expression, apoptotic cell number and DNA fragmentation ratio versus control animals. However, the animals in MICT, HICT, HIIT groups exhibited a significant (p < 0.05) increment in serum HDL-C and testosterone, Cyclin D1 and Cdk4 expressions and showed a significant (p < 0.05) reduction in serum LDL-C and triglyceride, p21 expression, apoptotic cell number and DNA fragmentation versus the HFD-sole group. In conclusion, a crosslink between cell cycle machinery and apoptosis of germ cells was revealed in the testicles of HFD-sole animals, and MICT, HICT and HIIT could ameliorate the obesity-induced impairments, respectively. This effect may be attributed to the effect of exercise training protocols on maintaining Cyclin D1 and Cdk4 and suppressing p21 expression levels in the testicles.


Assuntos
Apoptose , Proteínas de Ciclo Celular/metabolismo , Dieta Hiperlipídica/efeitos adversos , Treinamento Intervalado de Alta Intensidade/métodos , Obesidade/terapia , Condicionamento Físico Animal/métodos , Testículo/metabolismo , Animais , Proteínas de Ciclo Celular/genética , Lipídeos/análise , Masculino , Obesidade/etiologia , Obesidade/metabolismo , Obesidade/patologia , Ratos , Ratos Wistar , Testosterona/sangue
16.
Biochim Biophys Acta Mol Basis Dis ; 1866(8): 165820, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32360396

RESUMO

Glycemic control is essential to reduce the risk of complications associated with metabolic syndrome (MetS) and type 2 diabetes (T2D). Aerobic and resistance exercise performed alone or in combination improve glycemic control in both conditions. However, perceived lack of time and commitment are considered principal barriers to performing exercise regularly. High intensity interval training (HIIT) and sprint interval training (SIT) can be performed in a fraction of the time required for continuous aerobic exercise. A substantial scientific evidence indicates that HIIT/SIT improve glycemic control to a similar or greater extent than aerobic exercise in populations without MetS or T2D. Likewise, growing evidence suggest that HIIT/SIT improve the glycemic control during MetS and T2D. The aim of this review is to discuss the effects of interval training protocols on peripheral markers of glucose metabolism in patients with MetS and T2D.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Treinamento Intervalado de Alta Intensidade/métodos , Insulina/sangue , Síndrome Metabólica/metabolismo , Biomarcadores/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patologia , Metabolismo Energético , Hemoglobina A Glicada/metabolismo , Humanos , Resistência à Insulina , Fígado/metabolismo , Fígado/patologia , Síndrome Metabólica/genética , Síndrome Metabólica/patologia , Consumo de Oxigênio , Pâncreas/metabolismo , Pâncreas/patologia
17.
Clin Hemorheol Microcirc ; 75(4): 467-474, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32390610

RESUMO

BACKGROUND: Platelet activation is associated with abdominal obesity and exercise training is an important modulator of body weight. OBJECTIVE: We investigated the effects of two high intensity interval exercise (HIIE) protocols of different intensity and duration on platelet indices and platelet aggregation in overweight men. METHODS: Ten overweight men performed 6 intervals of 30s exercise at 110% of peak power output (PPO) interspersed by 3 : 30 min active recovery (1/7 protocol) at 40% of PPO and 6 intervals of 2 min exercise at 85% of PPO interspersed by 2 min active recovery (1/1 protocol) at 30% of PPO in two separate sessions. Platelet indices and platelet aggregation were measured before and immediately after both HIIEs. RESULTS: Platelet indices increased significantly following HIIE (P < 0.05), though, significant differences between the two protocols were only detected for platelet count, which was markedly increased following 1/1 protocol. Platelet aggregation increased significantly (P < 0.05) in response to the two HIIE protocols, with no significant difference being observed between the two protocols (P > 0.05). CONCLUSIONS: It is concluded that HIIE leads to transient increases in markers of thrombus formation and that work to rest ratio is an important factor when investigating the changes in thrombocytosis following HIIE.


Assuntos
Difosfato de Adenosina/metabolismo , Exercício Físico/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Sobrepeso/sangue , Agregação Plaquetária/fisiologia , Contagem de Plaquetas/métodos , Adulto , Humanos , Masculino , Adulto Jovem
18.
Int J Sports Physiol Perform ; 15(6): 808-815, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32365286

RESUMO

The growing prevalence and popularity of interval training necessitate additional guidelines in regard to maximal levels of time and intensity. PURPOSE: To correlate salivary hormones and time in varying heart-rate (HR) zones. The hypothesis was that chronic exercise durations >9% of total exercise time in the >90% maximum HR zone would lead to decreased variation in salivary cortisol concentration after exercise in a 2-bout high-intensity protocol compared with less or more time in this zone. METHODS: A total of 35 healthy adults who regularly exercised for an average of 8 hours per week recorded their HR during every training session for 3 weeks. Later, they completed an experimental day composed of two 30-minute high-intensity interval sessions separated by 4 hours of nonactive recovery. The authors collected saliva samples before, immediately following, and 30 minutes after each exercise session to assess changes in cortisol concentrations. RESULTS: There was a correlation between weekly time training at an intensity >90% maximum HR and the variables associated with overtraining. Salivary cortisol concentration fluctuated less in the participants who exercised in this extreme zone for >40 minutes per week (P < .001). CONCLUSION: Based on the current study data, for individuals who regularly exercise, 4% to 9% total training time above 90% maximum HR is the ideal duration to maximize fitness and minimize symptoms related to overreaching.


Assuntos
Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Hidrocortisona/metabolismo , Saliva/metabolismo , Adulto , Afeto/fisiologia , Aptidão Cardiorrespiratória/fisiologia , Aptidão Cardiorrespiratória/psicologia , Metabolismo Energético , Exercício Físico/psicologia , Feminino , Treinamento Intervalado de Alta Intensidade/psicologia , Humanos , Masculino , Sono/fisiologia , Fatores de Tempo
19.
BMC Public Health ; 20(1): 609, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32357869

RESUMO

BACKGROUND: High-intensity interval training (HIIT) elicits numerous health benefits, but little evidence is available regarding the feasibility of delivering school-based HIIT interventions. The aim of this study was to explore adolescents' perceptions of a 6-month, 3 × 30-min sessions per week, HIIT intervention delivered either before or after school. METHOD: Eighty adolescents allocated to the intervention group (13.3 ± 1.0 years; 45 boys) were invited to take part in semi-structured focus groups post-intervention. Participants were categorised as attendees (≥40% attendance) or non-attendees (< 5% attendance). Data were transcribed verbatim and thematically analysed deductively, with key emergent themes represented using pen profiles. RESULTS: Results showed that a school-based HIIT intervention can be an enjoyable form of exercise. Irrespective of attendance, similar facilitators and barriers to participating were highlighted, including benefits of participation, content of the exercise session and the intervention instructor. CONCLUSION: This study provides support for the delivery of a HIIT intervention in a school setting but highlights the importance of a flexible design and delivery to accommodate competing interests. There is a need to educate adolescents on the possible benefits of participation and to make the sessions enjoyable in order to increase their extrinsic and intrinsic motivation to sustain participation.


Assuntos
Asma/terapia , Terapia por Exercício/métodos , Terapia por Exercício/psicologia , Treinamento Intervalado de Alta Intensidade/métodos , Treinamento Intervalado de Alta Intensidade/psicologia , Motivação , Estudantes/psicologia , Adolescente , Feminino , Humanos , Masculino , Serviços de Saúde Escolar/estatística & dados numéricos
20.
J Int Soc Sports Nutr ; 17(1): 29, 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32460793

RESUMO

BACKGROUND: High-intensity interval training (HIIT) is an effective approach to improve physical fitness, but consuming beer, which is a regular practice in many physically active individuals, may interfere with these effects. The purposes of this study were to investigate the effects of a 10-week (2 days/week) HIIT program on cardiorespiratory fitness, muscle strength and power parameters, and also to assess the possible influence on them of a moderate consumption of beer (at least from Monday to Friday) or its alcohol equivalent. METHODS: Young (24 ± 6 years old) healthy adults (n = 73, 35 females) were allocated to five groups. Four groups participated in the HIIT intervention program while the fifth group was a control Non-Training group (n = 15). Participants in the training groups chose whether they preferred receiving alcohol or alcohol-free beverages. Those choosing alcohol were randomized to either beer or ethanol intake: (i) T-Beer group (alcohol beer, 5.4%; n = 13) or (ii) T-Ethanol (sparkling water with vodka, 5.4%; n = 14). Those choosing alcohol-free intake were randomized to (iii) T-Water group (sparkling water, 0.0%; n = 16), or (iv) T-0.0Beer group (alcohol-free beer, 0.0%; n = 15). Men ingested 330 ml of the beverage at lunch and 330 ml at dinner; women ingested 330 ml at dinner. Before and after the intervention, maximal oxygen uptake in absolute and relative terms (VO2max.), maximal heart rate, total test duration, hand grip strength and four types of vertical jumps were measured. RESULTS: HIIT induced significant improvements in absolute and relative values of VO2max, and total test duration (all p < 0.05) in all the training groups; also, clinical improvements were found in hand grip strength. These positive effects were not influenced by the regular intake of beer or alcohol. No changes in the vertical jumps occurred in any of the groups. CONCLUSIONS: A moderate beer or alcohol intake does not mitigate the positive effect of a 10-week HIIT on physical fitness in young healthy adults. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT03660579. Registered 20 September 2018. Retrospectively registered.


Assuntos
Bebidas Alcoólicas , Cerveja , Aptidão Cardiorrespiratória , Treinamento Intervalado de Alta Intensidade/métodos , Força Muscular , Aptidão Física , Adolescente , Adulto , Feminino , Humanos , Masculino , Fenômenos Fisiológicos da Nutrição Esportiva , Adulto Jovem
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