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1.
Nutrients ; 13(12)2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34959945

RESUMO

The COVID-19 pandemic and subsequent self-isolation exacerbated the problem of insufficient amounts of physical activity and its consequences. At the same time, this revealed the advantage of vitamin D. Thus, there was a need to verify the effects of those forms of training that can be performed independently. In this study, we examined the effects of Nordic walking (NW) and high intensity interval training (HIIT) with regard to the impact of the metabolite vitamin D. We assigned 32 overweight adults (age = 61 ± 12 years) to one of two training groups: NW = 18 and HIIT = 14. Body composition assessment and blood sample collection were conducted before starting the training programs and a day after their completion. NW training induced a significant decrease in myostatin (p = 0.05) concentration; however, the range was dependent on the baseline concentrations of vitamin D metabolites. This drop was accompanied by a significant negative correlation with the decorin concentration. Unexpectedly, NW caused a decrement in both forms of osteocalcin: undercarboxylated (Glu-OC) and carboxylated-type (Gla-OC). The scope of Glu-OC changes was dependent on a baseline concentration of 25(OH)D2 (r = -0.60, p = 0.01). In contrast, the HIIT protocol did not induce any changes. Overall results revealed that NW diminished the myostatin concentration and that this effect is more pronounced among adults with a sufficient concentration of vitamin D metabolites.


Assuntos
COVID-19 , Treinamento Intervalado de Alta Intensidade , Miostatina/sangue , Sobrepeso , SARS-CoV-2/metabolismo , Vitamina D/sangue , Idoso , COVID-19/sangue , COVID-19/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sobrepeso/sangue , Sobrepeso/fisiopatologia
2.
Nutrients ; 13(12)2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34959789

RESUMO

There is evidence that both omega-3 polyunsaturated fatty acids (n-3 PUFAs) and choline can influence sports performance, but information establishing their combined effects when given in the form of krill oil during power training protocols is missing. The purpose of this study was therefore to characterize n-3 PUFA and choline profiles after a one-hour period of high-intensity physical workout after 12 weeks of supplementation. Thirty-five healthy power training athletes received either 2.5 g/day of Neptune krill oilTM (550 mg EPA/DHA and 150 mg choline) or olive oil (placebo) in a randomized double-blind design. After 12 weeks, only the krill oil group showed a significant HS-Omega-3 Index increase from 4.82 to 6.77% and a reduction in the ARA/EPA ratio (from 50.72 to 13.61%) (p < 0.001). The krill oil group showed significantly higher recovery of choline concentrations relative to the placebo group from the end of the first to the beginning of the second exercise test (p = 0.04) and an 8% decrease in total antioxidant capacity post-exercise versus 21% in the placebo group (p = 0.35). In conclusion, krill oil can be used as a nutritional strategy for increasing the HS-Omega-3 Index, recover choline concentrations and address oxidative stress after intense power trainings.


Assuntos
Desempenho Atlético/fisiologia , Colina/administração & dosagem , Euphausiacea , Óleos de Peixe/administração & dosagem , Treinamento Intervalado de Alta Intensidade , Adulto , Animais , Antioxidantes/metabolismo , Colina/sangue , Suplementos Nutricionais , Método Duplo-Cego , Ácidos Graxos Ômega-3/sangue , Feminino , Voluntários Saudáveis , Humanos , Masculino
3.
Artigo em Inglês | MEDLINE | ID: mdl-34948733

RESUMO

Lack of time is seen as a barrier to maintaining a physically active lifestyle. In this sense, interval training has been suggested as a time-efficient strategy for improving health, mainly due to its potential to increase cardiorespiratory fitness. Currently, the most discussed interval training protocols in the literature are the high-intensity interval training (HIIT) and the sprint interval training (SIT). Objective: We investigated, through a systematic review and meta-analysis, which interval training protocol, HIIT or SIT, promotes greater gain in cardiorespiratory fitness (V˙O2max/peak). The studies were selected from the PubMed (MEDLINE), Scopus and Web of Science databases. From these searches, a screening was carried out, selecting studies that compared the effects of HIIT and SIT protocols on V˙O2max/peak. A total of 19 studies were included in the final analysis. Due to the homogeneity between studies (I2 = 0%), fixed-effects analyses were performed. There was no significant difference in the V˙O2max/peak gains between HIIT and SIT for the standardized mean difference (SMD = 0.150; 95% CI = -0.038 to 0.338; p = 0.119), including studies that presented both measurements in mL·kg-1·min-1 and l·min-1; and raw mean differences (RMD = 0.921 mL·kg-1·min-1; 95% CI = -0.185 to 2.028; p = 0.103) were calculated only with data presented in mL·kg-1·min-1. We conclude that the literature generates very consistent data to confirm that HIIT and SIT protocols promote similar gains in cardiorespiratory fitness. Thus, for this purpose, the choice of the protocol can be made for convenience.


Assuntos
Aptidão Cardiorrespiratória , Treinamento Intervalado de Alta Intensidade , Estilo de Vida , Consumo de Oxigênio
4.
Artigo em Inglês | MEDLINE | ID: mdl-34949008

RESUMO

BACKGROUND: Firefighting is a strenuous profession requiring adequate levels of fitness for effective job performance. Providing firefighters with a safe and effective fitness program is essential for optimal performance. The purpose of this project was to examine changes in various parameters of physical fitness and firefighter ability following a 7-week high intensity functional training (HIFT) program. METHODS: Participants were male firefighter recruits (N = 89; age = 27.1 ± 4.2 years, height = 1.78 ± 0.1 m, BMI = 28.1 ± 4.2) enrolled in a Basic Operations Firefighter Academy. Fitness and firefighting ability (via the Academy Firefighter Challenge) were assessed at Weeks 1 and 7 of the Academy. RESULTS: Significant improvements in both fitness and firefighter ability were seen following the HIFT program. Specifically, fitness (BMI, cardiovascular fitness, muscular endurance) improved significantly [Hotelling's T2 = 8.98, F(5, 84) = 150.92, p < 0.001, η2p = 0.90]. Firefighter ability also improved significantly [Hotelling's T2 = 3.95, F(7, 88) = 46.26, p < 0.001, η2p = 0.80]. CONCLUSIONS: Following a 7-week Basic Operations Firefighter Academy that included daily HIFT, significant increases in fitness and firefighting ability were observed. These findings suggest that HIFT appears to be an effective means of improving fitness and firefighting ability in recruit firefighters.


Assuntos
Bombeiros , Treinamento Intervalado de Alta Intensidade , Adulto , Exercício Físico , Teste de Esforço , Humanos , Masculino , Aptidão Física , Adulto Jovem
5.
J Spec Oper Med ; 21(4): 112-115, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34969140

RESUMO

High-intensity functional training (HIFT) involves high-volume and high-intensity physical activities with short rest periods between movements and the use of multiple-joint exercises. This paper analyzes narrative and systematic reviews covering studies of injuries sustained during HIFT. Two narrative and six systematic reviews on injuries during HIFT were identified. Seven reviews concluded that the injury incidences or injury rates during HIFT were similar to those of comparable sports and exercise programs. The most often injured anatomic locations were shoulders, backs, and knees. The most comprehensive and recent review involved 21 retrospective and three prospective studies. In this review, mean ± standard deviation (SD) injury prevalence was 35% ± 15%, the injury rate was approximately 3 ± 5 injuries/1,000 hours of training, and the prevalence of injuries requiring surgery was 6% ± 5%. Most injuries were associated with weightlifting exercises, especially deadlifts, snatches, clean and jerks, and overhead presses. Other risk factors included participation time in HIFT, participation in competition, prior injuries, weekly training frequency, male sex, older age, and alternating training loads. Although most studies included in these reviews were of lower methodologic quality, current evidence suggests that injury rates in HIFT are similar to those of other exercise activities. More high-quality prospective studies are needed to fully evaluate HIFT safety.


Assuntos
Treinamento Intervalado de Alta Intensidade , Idoso , Exercício Físico , Terapia por Exercício , Humanos , Masculino , Estudos Prospectivos , Estudos Retrospectivos
6.
Artigo em Inglês | MEDLINE | ID: mdl-34769831

RESUMO

High-intensity interval running (HIIT-R) and high-intensity functional training (HIFT) are two forms of HIIT exercise that are commonly used. The purpose of this study was to determine the effects of HIFT on aerobic capacity and body composition when compared to HIIT-R in females. Twenty healthy, untrained female university students (age 20.5 ± 0.7 year) were randomly assigned to a 12-week HIIT-R or HIFT intervention. The HIIT-R group involved a 30 s maximal shuttle run with a 30 s recovery period, whereas the HIFT involved multiple functional exercises with a 2:1 work-active recovery ratio. Body composition, VO2max, and muscle performance were measured before and post intervention. As a result, HIIT-R and HIIT-F stimulated similar improvements in VO2max (17.1% ± 5.6% and 12.7% ± 6.7%, respectively, p > 0.05). Only the HIIT-F group revealed significant improvements in muscle performance (sit-ups, 16.5% ± 3.1%, standing broad jump 5.1% ± 2.2%, p < 0.05). Body fat percentage decreased (17.1% ± 7.4% and 12.6% ± 5.1%, respectively, p < 0.05) in both HIIT-R and HIIT-F with no between-group differences. We concluded that HIFT was equally effective in promoting body composition and aerobic fitness compared to HIIT-R. HIFT resulted in improved muscle performance, whereas the HIIT-R protocol demonstrated no gains.


Assuntos
Treinamento Intervalado de Alta Intensidade , Corrida , Adulto , Composição Corporal , Feminino , Humanos , Estudantes , Universidades , Adulto Jovem
7.
BMJ Open ; 11(11): e048281, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34794987

RESUMO

INTRODUCTION: COVID-19 is associated with a marked systemic inflammatory response with concomitant cardiac injury and remodelling, but it is currently unknown whether the latter is reversible. Given that high-intensity interval training (HIIT) is a powerful stimulus to improve cardiorespiratory fitness while also eliciting marked anti-inflammatory effects, it may be an important countermeasure of reducing cardiopulmonary morbidity following COVID-19. METHODS AND ANALYSIS: 40 COVID-19 survivors who have been discharged from hospital will be included in this investigator-blinded randomised study with a 12-week HIIT intervention. Patients will be 1:1 block-randomised by sex to either a supervised HIIT exercise group or standard care (control group). The main hypothesis is that a 12-week HIIT scheme is a safe way to improve loss of cardiac mass and associated cardiorespiratory fitness, despite hypothesised limited HIIT-induced changes in conventional lung function indices per se. Ultimately, we hypothesise that the HIIT scheme will reduce post-COVID-19 symptoms and improve quality of life. ETHICS AND DISSEMINATION: This study is approved by the Scientific Ethical Committee at the Capital Region of Denmark (H-20033733, including amendments 75068 and 75799) and registered at ClinicalTrials.gov (NCT04647734, pre-results). The findings will be published in a peer-reviewed journal, including cases of positive, negative and inconclusive results.Trial registration number NCT04549337.


Assuntos
COVID-19 , Aptidão Cardiorrespiratória , Treinamento Intervalado de Alta Intensidade , Humanos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , SARS-CoV-2 , Resultado do Tratamento
9.
PLoS One ; 16(10): e0257607, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34597330

RESUMO

INTRODUCTION: Exercise training is strongly recommended as a therapeutic approach to treat individuals with heart failure. High-intensity exercise training modalities still controversial in this population. The study aims to preliminary assess the consequences of high-intensity exercise training modalities, aerobic interval training (HIIT) and progressive high circuit-resistance training (CRT), on primarily endothelial function and cardiorespiratory fitness, and secondly on muscle strength and physical performance in heart failure patients. METHODS: This preliminary multicentric randomized controlled trial comprised 23 heart failure patients, aged 56 ± 10 years old, mainly New York Heart Association classification I and II (%), hemodynamically stable, who compromise at least 36 exercise sessions of a randomly assigned intervention (HIIT, CRT or control group). Endothelial function, cardiopulmonary exercise testing, muscle strength and physical performance were completed at baseline and post-intervention. RESULTS: Although no effects on endothelial function; both HIIT and CRT modalities were able to produce a positive effect on [Formula: see text] peak (HIIT = +2.1±6.5, CRT = +3.0±4.2 and control group = -0.1± 5.3 mL/kg/min, time*group p-value<0,05) and METs (HIIT = +0.6±1.8, CRT = +0.9±1.2 and control group = 0±1.6, time*group p-value<0,05). Only HIIT increased isokinetic torque peak (HIIT = +8.8±55.8, CRT = 0.0±60.7 and control group = 1.6±57.6 Nm) matched p-value<0,05. Regarding the physical performance, the CRT modality reduced chair stand test completion time (HIIT = -0.7±3.1, CRT = -3.3±3.2 and control group = -0.3±2.5 s, matched p-value<0,05 and HIIT improved global physical performance(time*group p<0,05). CONCLUSION: This preliminary study trends to indicate for the first time that high-intensity interval training promotes a jointly superior effect compared to progressive high intensity circuit-resistance training by improving cardiorespiratory fitness, muscular strength, and physical performance. Further research with larger cohort is necessary. CLINICAL TRIAL REGISTRATION NUMBER: ReBEC RBR-668c8v.


Assuntos
Aptidão Cardiorrespiratória/fisiologia , Exercícios em Circuitos , Endotélio Vascular/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Treinamento Intervalado de Alta Intensidade , Treinamento de Força , Idoso , Composição Corporal/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular/fisiologia , Resultado do Tratamento
10.
Pediatrics ; 148(5)2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34663681

RESUMO

OBJECTIVES: Physical inactivity is an important health concern worldwide. In this study, we examined the effects of an exercise intervention on children's academic achievement, cognitive function, physical fitness, and other health-related outcomes. METHODS: We conducted a population-based cluster randomized controlled trial among 2301 fourth-grade students from 10 of 11 public primary schools in 1 district of Ulaanbaatar between February and December 2018. Schools were allocated to an intervention or control group with 5 schools each by using urban and mixed residential area stratified block randomization. The intervention group received a 3-minute high-intensity interval exercise program that included jumps, squats, and various steps implemented twice weekly over 10 weeks for 10 to 25 minutes per session. The control group received the usual physical education class. The primary outcome was academic achievement assessed by scores on the national examination. A linear mixed-effects model was applied. The difference between preintervention and post intervention was compared by least-squares means, estimated on the basis of the interaction of group, measurement time point, and school location. Only 1 statistician, responsible for the analysis, was blinded. RESULTS: Of 2301 students, 2101 (1069 intervention; 1032 control) were included in the analysis. Intervention group members in an urban area showed an 8.36-point improvement (95% confidence interval: 6.06 to 10.66) in academic scores when compared with the control group, whereas those in a mixed residential area showed a 9.55-point improvement (95% confidence interval: 6.58 to 12.51). No intervention-associated injuries were observed. CONCLUSIONS: The exercise program significantly improved children's academic achievement.


Assuntos
Sucesso Acadêmico , Cognição , Treinamento Intervalado de Alta Intensidade/métodos , Aptidão Física , Criança , Intervalos de Confiança , Feminino , Humanos , Masculino , Mongólia , Educação Física e Treinamento , Instituições Acadêmicas , Estudantes/estatística & dados numéricos , Fatores de Tempo
11.
FASEB J ; 35(11): e21988, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34665879

RESUMO

Interval training (IT) results in improved fatigue resistance in skeletal muscle mainly due to an increased aerobic capacity, which involves increased muscle mitochondrial content and/or improved mitochondrial function. We hypothesized that IT with high-intensity contractions is more effective in increasing mitochondrial function, and hence fatigue resistance, than low-intensity contractions. To study this hypothesis without interference from differences in muscle fiber recruitment obliged to occur during voluntary contractions, IT was performed with in situ supramaximal electrical stimulation where all muscle fibers are recruited. We compared the effect of IT with repeated low-intensity (20 Hz stimulation, IT20) and high-intensity (100 Hz stimulation, IT100) contractions on fatigue resistance and mitochondrial content and function in mouse plantar flexor muscles. Muscles were stimulated every other day for 4 weeks. The averaged peak torque during IT bouts was 4.2-fold higher with IT100 than with IT20. Both stimulation protocols markedly improved in situ fatigue resistance, although the improvement was larger with IT100. The citrate synthase activity, a biomarker of mitochondrial content, was similarly increased with IT20 and IT100. Conversely, increased expression of mitochondrial respiratory chain (MRC) complexes I, III, and IV was only observed with IT100 and this was accompanied by increases in MRC supercomplex formation and pyruvate-malate-driven state 3 respiration in isolated mitochondria. In conclusion, the IT-induced increase in fatigue resistance is larger with high-intensity than with low-intensity contractions and this is linked to improved mitochondrial function due to increased expression of MRC complexes and assembly of MRC supercomplexes.


Assuntos
Treinamento Intervalado de Alta Intensidade/métodos , Mitocôndrias/metabolismo , Contração Muscular , Fadiga Muscular , Músculo Esquelético/metabolismo , Animais , Biomarcadores/metabolismo , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Músculo Esquelético/citologia
12.
J Sports Med Phys Fitness ; 61(10): 1416-1422, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34652089

RESUMO

BACKGROUND: Oxidative stress and mitochondrial dysfunction can be tracked down in most liver diseases like non-alcoholic fatty liver disease (NAFLD). The most recommended preventative method is lifestyle modification, especially exercise. The aim of this study was the investigation of changes in the indexes of mitochondrial biogenesis and fatty liver indicators in rat following continuous and high intensity interval training. METHODS: Thirty healthy male rats were divided into three control (C=10), Continuous swimming training (CT=10) and High intensity interval swimming training groups (HIIT=10). The training groups performed their specific exercises 5 days a week for 8 weeks. 24 h after the last training session in order to prepare the serum, a blood sample was taken from the left ventricle of the rats. In addition, liver tissue was extracted and the SIRT3, PGC-1α, GSH:GSSG, MDA, LDL, HDL, LDL:HDL, TG, TC, AST, ALT and FBS variables were measured by ELISA and analysis of blood biochemistry. RESULTS: Continuous training (CT) increased the levels of PGC-1α, SIRT3 and significantly reduced LDL, LDL:HDL, TG and FBS (P<0.05) levels. High-intensity interval training (HIIT) caused a significant increase in SIRT3 and a significant decrease in FBS (P<0.05) levels. CONCLUSIONS: Adaptations resulting from further aerobic exercise can increase mitochondrial biogenesis factors such as PGC-1α and SIRT3 in hepatocytes, improve this process in hepatocytes, and ultimately improve the fatty liver markers. Therefore, CT may be more effective than HIIT in preventing fatty liver disease.


Assuntos
Treinamento Intervalado de Alta Intensidade , Hepatopatia Gordurosa não Alcoólica , Condicionamento Físico Animal , Animais , Masculino , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Biogênese de Organelas , Ratos
13.
JMIR Mhealth Uhealth ; 9(10): e28124, 2021 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-34673536

RESUMO

BACKGROUND: Patients with inflammatory rheumatic diseases (IRDs) experience disease-related barriers to physical training. Compared with the general population, IRD patients are reported to have reduced maximal oxygen uptake (VO2max) and physical activity levels. Supervised high-intensity interval training (HIIT) is documented to counteract the reduced VO2max and poor cardiovascular health associated with IRDs. However, supervised HIIT is resource demanding. OBJECTIVE: This study sought to investigate if self-administered 4×4-min HIIT guided by a smartphone app (Myworkout GO) could yield similar HIIT-induced effects as standard 4×4-min HIIT performed under the guidance and supervision of health care professionals. The effects studied were on VO2max and health-related quality of life (HRQoL). METHODS: Forty patients (33 female patients, mean age 48 years, SD 12 years; 7 male patients, mean age 52 years, SD 11 years) diagnosed with rheumatoid arthritis, spondyloarthritis, or systemic lupus erythematosus were randomized to a supervised group (SG) or an app group (AG). Both groups were instructed to perform 4×4-min intervals with a rate of perceived exertion of 16 to 17, corresponding to 85% to 95% of the maximal heart rate, twice a week for 10 weeks. Treadmill VO2max and HRQoL measured using RAND-36 were assessed before and after the exercise period. RESULTS: VO2max increased (P<.001) in both groups after 10 weeks of HIIT, with improvements of 3.6 (SD 1.3) mL/kg/min in the SG and 3.7 (SD 1.5) mL/kg/min in the AG. This was accompanied by increases in oxygen pulse in both groups (P<.001), with no between-group differences apparent for either measure. Improvements in the HRQoL dimensions of bodily pain, vitality, and social functioning were observed for both groups (P<.001 to P=.04). Again, no between-group differences were detected. CONCLUSIONS: High-intensity 4×4-min interval training increased VO2max and HRQoL, contributing to patients' reduced cardiovascular disease risk, improved health and performance, and enhanced quality of life. Similar improvements were observed following HIIT when IRD patients were guided using perceived exertion by health care professionals or the training was self-administered and guided by the app Myworkout GO. Utilization of the app may help reduce the cost of HIIT as a treatment strategy in this patient population. TRIAL REGISTRATION: ClinicalTrials.gov NCT04649528; https://clinicaltrials.gov/ct2/show/NCT04649528.


Assuntos
Treinamento Intervalado de Alta Intensidade , Doenças Reumáticas , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Doenças Reumáticas/terapia , Smartphone
14.
Artigo em Inglês | MEDLINE | ID: mdl-34682481

RESUMO

The low-carbohydrate high-fat (LCHF) diet has recently been subject to attention on account of its reported influences on body composition and physical performance. However, the combined effect of LCHF with high-intensity interval training (HIIT) is unclear. A systematic review and meta-analysis were conducted to explore the effect of the LCHF diet combined with HIIT on human body composition (i.e., body weight (BM), body mass index (BMI), fat mass (FM), body fat percentage (BFP), fat-free mass (FFM)) and maximal oxygen uptake (VO2max). Online libraries (PubMed, Web of Science, EMBASE, Cochrane Library, EBSCO, CNKI, Wan Fang) were used to search initial studies until July 2021, from which 10 out of 2440 studies were included. WMD served as the effect size with a confidence interval value of 95%. The results of meta-analysis showed a significant reduction in BM (WMD = -5.299; 95% CI: -7.223, -3.376, p = 0.000), BMI (WMD = -1.150; 95% CI: -2.225, -0.075, p = 0.036), BFP (WMD = -2.787; 95% CI: -4.738, -0.835, p = 0.005) and a significant increase in VO2max (WMD = 3.311; 95% CI: 1.705, 4.918, p = 0.000), while FM (WMD = -2.221; 95% CI: -4.582, 0.139, p = 0.065) and FFM (WMD = 0.487; 95% CI: -3.512, 4.469, p = 0.814) remained unchanged. In conclusion, the LCHF diet combined with HIIT can reduce weight and fat effectively. This combination is sufficient to prevent muscle mass loss during LCHF, and further enhance VO2max. Further research might be required to clarify the effect of other types of exercise on body composition and physical performance during LCHF.


Assuntos
Treinamento Intervalado de Alta Intensidade , Composição Corporal , Carboidratos , Dieta Hiperlipídica , Humanos , Oxigênio
15.
Artigo em Inglês | MEDLINE | ID: mdl-34682594

RESUMO

Measuring exercise variables is one of the most important points to consider to maximize physiological adaptations. High-intensity interval training (HIIT) is a useful method to improve both cardiovascular and neuromuscular performance. The 30-15IFT is a field test reflecting the effort elicited by HIIT, and the final velocity reached in the test is used to set the intensity of HIIT during the training session. In order to have a valid measure of the velocity during training, devices such as GPS can be used. However, in several situations (e.g., indoor setting), such devices do not provide reliable measures. The aim of the study was to predict exact running velocity during the 30-15IFT using accelerometry-derived metrics (i.e., Player Load and Average Net Force) and heart rate (HR) through a machine learning (ML) approach (i.e., Support Vector Machine) with a leave-one-subject-out cross-validation. The SVM approach showed the highest performance to predict running velocity (r = 0.91) when compared to univariate approaches using PL (r = 0.62), AvNetForce (r = 0.73) and HR only (r = 0.87). In conclusion, the presented multivariate ML approach is able to predict running velocity better than univariate ones, and the model is generalizable across subjects.


Assuntos
Treinamento Intervalado de Alta Intensidade , Corrida , Acelerometria , Benchmarking , Exercício Físico , Teste de Esforço , Frequência Cardíaca , Humanos , Aprendizado de Máquina
16.
Artigo em Inglês | MEDLINE | ID: mdl-34682718

RESUMO

OBJECTIVES: To use a quantitative approach to examine the effects of high-intensity interval training (HIIT) interventions on sleep for adults. METHODS: PubMed, Ebsco, Web of Science, Cochrane Central Register of Controlled Trials, the China National Knowledge Infrastructure, and Wanfang Data were searched from their inception to December 2020. Intervention studies with a control group that examined the effects of HIIT interventions on sleep were included in this meta-analysis. The risk of bias was assessed using the tool provided by the Cochrane Handbook for Systematic Reviews of Interventions. Effect sizes (ESs), calculated as weighted mean difference (WMD) and standardized mean difference (SMD), were used to examine the effects of objective outcomes and subjective outcomes separately. RESULTS: A large increase in sleep quality (SQ) reflected by the Pittsburgh Sleep Quality Index global scores [WMD = -0.90, 95%CI (-1.72, -0.07), p = 0.03, n = 8] and a small-to-medium favorable effect on sleep efficiency (SE) [SMD = 0.43, 95%CI (0.20, 0.65), p = 0.0002, n = 10] were found after HIIT intervention. In addition, sub-analyses results suggest that ESs were moderated by the type, duration and frequency, as well as the length of the HIIT intervention. CONCLUSIONS: HIIT may be a promising way to improve overall subjective SQ and objective SE. PROSPERO, protocol registration number: CRD42021241734.


Assuntos
Treinamento Intervalado de Alta Intensidade , Transtornos Mentais , Adulto , China , Humanos , Sono
17.
Nutrients ; 13(10)2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34684532

RESUMO

High-intensity interval training (HIIT) and linseed oil (LO) supplementation are effective strategies to reduce obesity-induced oxidative stress. Our aim was to determine whether the HIIT + LO combination prevents obesity-induced oxidative stress in high fat diet (HFD)-fed rats. HFD-fed 8-week-old, male, Wistar rats were subdivided in four groups: HFD, LO (2% of sunflower oil replaced with 2% of LO in the HFD), HIIT (4 days/week for 12 weeks), and HIIT + LO. Wistar rats fed a low-fat diet (LFD) were used as controls. Epididymal and subcutaneous adipose tissue, gastrocnemius muscle, liver, and plasma samples were collected to measure oxidative stress markers (AOPP, oxLDL), antioxidant (SOD, CAT, and GPx activities) and pro-oxidant (NOx and XO) enzyme activities. Compared with the LFD, the HFD altered the pro/antioxidant status in different tissues (increase of AOPP, oxLDL, SOD and catalase activities in plasma, and SOD activity increase in liver and decrease in adipose tissues) but not in gastrocnemius. LO upregulated CAT activity and decreased NOx in liver. HIIT alleviated HFD negative effects in liver by reducing SOD and NOx activities. Moreover, the HIIT + LO combination potentiated SOD activity upregulation in subcutaneous tissue. HIIT and LO supplementation have independent beneficial effects on the pro/antioxidant balance. Their association promotes SOD activity in subcutaneous adipose tissue.


Assuntos
Suplementos Nutricionais , Comportamento Alimentar , Treinamento Intervalado de Alta Intensidade , Óleo de Semente do Linho/farmacologia , Obesidade/patologia , Estresse Oxidativo , Animais , Antioxidantes/metabolismo , Biomarcadores/sangue , Catalase/metabolismo , Comportamento Alimentar/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Nitratos/metabolismo , Obesidade/sangue , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar , Tela Subcutânea/efeitos dos fármacos , Tela Subcutânea/metabolismo , Superóxido Dismutase/metabolismo , Regulação para Cima/efeitos dos fármacos
19.
Artigo em Inglês | MEDLINE | ID: mdl-34574554

RESUMO

This study examined the immediate and sustained effects of high-intensity interval exercise (HIIE) and moderate-intensity continuous exercise (MICE) on cognitive flexibility in young adults. Participants (n = 56) engaged in (1) a session of HIIE, involving 10 sets of one-minute treadmill running at an intensity targeting 90% heart rate reserve (HRR) interspersed with self-paced walking at 50% HRR; (2) a session of MICE, involving a 20 min treadmill running at an intensity of 40-59% HRR; and (3) a control session, involving 24 min of resting on separate days in a counterbalanced order. Using a more-odd shifting task, cognitive flexibility was assessed before the intervention (t0), immediately after the session (t1), and then at 30 min (t2) after the session. During the more-odd shifting task, the switch cost of response time (RT) immediately after the HIIE was significantly reduced compared to that before exercise, suggesting beneficial effects on cognitive flexibility. Additionally, the impacts of HIIE were maintained for 30 min post-exercise. However, improved cognitive flexibility was not observed until 30 min after the MICE intervention. HIIE might represent a time-efficient approach for enhancing cognitive flexibility.


Assuntos
Treinamento Intervalado de Alta Intensidade , Cognição , Exercício Físico , Teste de Esforço , Frequência Cardíaca
20.
PLoS One ; 16(9): e0257685, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34587217

RESUMO

OBJECTIVE: High intensity interval training (HIIT) is a time-efficient exercise modality to improve cardiorespiratory fitness, and has recently been popularised by social media influencers. However, little is known regarding acute physiological and perceptual responses to these online protocols compared to HIIT protocols used within research. The aim was to investigate acute physiological, perceptual and motivational responses to two HIIT protocols popular on social media, and compare these to two evidence-based protocols. METHODS: Twenty-seven recreationally active (>1 exercise session /week) participants (Age: 22±3y, BMI: 24.3±2.4) completed a randomised cross-over study, whereby each participant completed four HIIT protocols, two already established in research (Ergo-60:60 (cycling 10x60s at 100%Wmaxwith 60s rest), BW-60:60 (body-weight exercises 10x60swith 60s rest)) and two promoted on social media (SM-20:10 (body-weight exercises 20x20swith 10s rest) and SM-40:20 (body-weight exercises 15x40s with 20s rest)). Blood lactate, heart rate (HR), feeling scale (FS), felt arousal scale (FSA), enjoyment and perceived competence were measured in response to each protocol. RESULTS: Significant differences were observed between BW-60:60 and SM-20:10 for the proportion of intervals meeting the ACSM high-intensity exercise criterion (>80% of HRmax) (BW-60:60 93±10%, SM-20:10 74±20%, P = 0.039) and change in lactate (BW-60:60 +7.8±3.7mmol/L, SM-20:10 +5.5±2.6mmol/L, P = 0.001). The percentage of time spent above the criterion HR was also significantly lower in SM-20:10 compared to all other protocols (Ergo-60:60 13.9±4.9min, BW-60:60 13.5±3.5min, SM-40:20 12.1±2.4min, SM-20:10 7.7±3.1, P<0.05). No differences were observed in lowest reported FS between protocols (P = 0.268), but FS decreased linearly throughout Ergo-60:60 and BW-60:60 (first vs. last interval P<0.05), but not in SM-20:10 or SM-40:20 (P>0.05). Enjoyment was higher upon completion of BW-60:60 compared to Ergo-60:60 and SM-40:20 (P<0.05). CONCLUSIONS: This study shows that HIIT protocols available on social media offer an interesting real-world alternative for promoting exercise participation. Future studies should continue to investigate these highly popular and practical HIIT protocols.


Assuntos
Aptidão Cardiorrespiratória/fisiologia , Coração/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Ácido Láctico/sangue , Participação do Paciente/estatística & dados numéricos , Adulto , Peso Corporal , Estudos Cross-Over , Medicina Baseada em Evidências , Feminino , Promoção da Saúde , Frequência Cardíaca , Humanos , Masculino , Distribuição Aleatória , Mídias Sociais , Adulto Jovem
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