Search results for "O2"

Effect of β-Blocker Withdrawal on Functional Capacity in Heart Failure and Preserved Ejection Fraction

2021

BACKGROUND Chronotropic incompetence has shown to be associated with a decrease in exercise capacity in heart failure with preserved ejection fraction (HFpEF), yet b-blockers are commonly used in HFpEF despite the lack of robust evidence. OBJECTIVES This study aimed to evaluate the effect of b-blocker withdrawal on peak oxygen consumption (peak VO2) in patients with HFpEF and chronotropic incompetence. METHODS This is a multicenter, randomized, investigator-blinded, crossover clinical trial consisting of 2 treatment periods of 2 weeks separated by a washout period of 2 weeks. Patients with stable HFpEF, New York Heart Association functional classes II and III, previous treatment with b-bloc…

Post-exercise heart rate variability of endurance athletes after different high-intensity exercise interventions

2007

Methodological problems have limited the number of studies on heart rate variability (HRV) dynamics immediately after exercise. We used the short-time Fourier transform method to study immediate (5 min) and slow (30 min) recovery of HRV after different high-intensity exercise interventions. Eight male athletes performed two interval interventions at 85% and 93% (IV(85) and IV(93)) and two continuous interventions at 80% and 85% (CO(80) and CO(85)) of the velocity at VO2max (vVO2max). We found no increase in high frequency power (HFP), but low frequency (LFP) and total power (TP) increased (P<0.05) during the first 5 min of the recovery after each intervention. During the 30-min recovery, HF…

Adaptations to aerobic interval training: interactive effects of exercise intensity and total work duration

2011

To compare the effects of three 7-week interval training programs varying in work period duration but matched for effort in trained recreational cyclists. Thirty-five cyclists (29 male, 6 female, VO(2peak) 52 ± 6 mL kg/min) were randomized to four training groups with equivalent training the previous 2 months (∼6 h/wk, ∼1.5 int. session/wk). Low only (n=8) trained 4-6 sessions/wk at a low-intensity. Three groups (n=9 each) trained 2 sessions/wk × 7 wk: 4 × 4 min, 4 × 8 min, or 4 × 16 min, plus 2-3 weekly low-intensity bouts. Interval sessions were prescribed at the maximal tolerable intensity. Interval training was performed at 88 ± 2, 90 ± 2, and 94 ± 2% of HR(peak) and 4.9, 9.6, and 13.2 …

Which exercise prescriptions optimize V̇O2max during cancer treatment?—A systematic review and meta-analysis

2019

Author's accepted version (post-print). This is the peer reviewed version of the following article: Bjørke, A. C. H., Sweegers, M. G., Buffart, L. M., Raastad, T., Nygren, P. & Berntsen, S. (2019). Which exercise prescriptions optimize V̇O2max during cancer treatment? – A systematic review and meta‐analysis. Scandinavian Journal of Medicine & Science in Sports, 29(9), 1274-1287, which has been published in final form at https://doi.org/10.1111/sms.13442. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. Available from 30/04/2020. The aims of the present systematic review and meta‐analysis were to investigate…

Effects of exercise training on oxygen uptake in coronary heart disease: a systematic review and meta-analysis

2010

It is not known to what extent exercise programs increase maximal oxygen uptake (VO(2max)) in patients with coronary heart diseases (CHD). The purpose of this study is to determine the effect of exercise interventions on VO(2max) in subjects with CHD. Database search of randomized controlled trials was conducted from PubMed. Studies were included that reported the characteristics and effects of exercise interventions in subjects with CHD, included a non-exercise control group and measured VO(2max) using direct measurement method. Eighteen studies were eligible. Exercise interventions increased VO(2max) by 2.6 +/- 1.6 and 0.3 +/- 1.4 mL/kg/min in the training and control groups, respectively…

2021

Background Physical activity alleviates chronic stress. The latest research suggests a relationship between resilience and physical fitness. Beneficial adaptations of the hypothalamic-pituitary-adrenal axis, sympathetic nervous system, endocannabinoid system, and tryptophan pathway, which are induced by an active lifestyle, are considered to be conducive to resilience. However, detailed knowledge on the molecular link between the effects of acute and chronic physical exercise and improved resilience to stress in humans is missing. Moreover, the relationship between innate and acquired aerobic capacity and resilience is poorly understood. Objective The aim of this study is to implement a hu…

Cardiorespiratory fitness is not associated with risk of venous thromboembolism: a cohort study

2019

Objectives. The inverse and independent association between cardiorespiratory fitness (CRF) and arterial thrombotic disease is well established. However, the potential association between CRF and venous thromboembolism (VTE) is not well known. We aimed to assess the prospective association of CRF with the risk of VTE. Design. Cardiorespiratory fitness, as measured by maximal oxygen uptake (VO2max), was assessed using a respiratory gas exchange analyser in 2,249 men aged 42-61 years without a history of VTE at baseline in the Kuopio Ischemic Heart Disease prospective cohort. Cox-regression models were used to calculate hazard ratios (HR) with 95% confidence interval (CI) for VTE. We correcte…

Optimal Physical Training During Military Basic Training Period

2015

The goal for military basic training (BT) is to create a foundation for physical fitness and military skills of soldiers. Thereafter, more advanced military training can safely take place. Large differences in the initial physical performance of conscripts or recruits have led military units to develop more safe and effective training programs. The purpose of this review article was to describe the limiting factors of optimal physical training during the BT period. This review revealed that the high volume of low-intensity physical activity combined with endurance-type military training (like combat training, prolonged physical activity, and field shooting) during BT interferes with optimal…

Cardiopulmonary exercise testing in COVID-19 patients at 3 months follow-up☆

2021

Abstract Background Long-term effects of Coronavirus Disease of 2019 (COVID-19) are of utmost relevance. We aimed to determine: 1) the functional capacity of COVID-19 survivors by cardiopulmonary exercise testing (CPET); 2) the characteristics associated with cardiopulmonary exercise testing (CPET) performance; 3) the safety and tolerability of CPET. Methods We prospectively enrolled consecutive patients with laboratory-confirmed COVID-19 from Azienda Sanitaria Locale 3, Genoa. Three months after hospital discharge a complete clinical evaluation, trans-thoracic echocardiography, CPET, pulmonary function tests, and dominant leg extension (DLE) maximal strength measurement were performed. Res…

Transporta plūsmu kustības ātruma un strukturālo izmaiņu modelēšana Valdemāra ielas kanjona posmos

2015

Bakalaura darba ietvaros pētīta autotransporta radītā atmosfēras piesārņojuma izplatība Rīgā, Valdemāra ielas kanjonā. Kā indikators ietekmes novērtēšanai izmantotas slāpekļa dioksīda koncentrācijas, kuras cieši korelē ar transporta līdzekļu plūsmas intensitāti; bez tam regulāri tiek pārsniegti slāpekļa dioksīdam noteiktie stundas un gada normatīvi. Piesārņojuma izplatība novērtēta izmantojot matemātisko modelis OSPM, kurš speciāli izstrādāts transporta radītā piesārņojuma dispersijai un raksturošanai. Darbā aprakstīta transporta plūsmas dinamika dažādiem dienu profiliem un izveidota datu bāze modelēšanai, raksturota piesārņojuma problemātika ielu kanjonos, modelēšanas ceļā novērtēta apbūve…