scholarly journals Cardiorespiratory fitness modulates the acute flow-mediated dilation response following high-intensity but not moderate-intensity exercise in elderly men

2017 ◽  
Vol 122 (5) ◽  
pp. 1238-1248 ◽  
Author(s):  
Tom G. Bailey ◽  
Maria Perissiou ◽  
Mark Windsor ◽  
Fraser Russell ◽  
Jonathan Golledge ◽  
...  
Keyword(s):  
Endothelial Function ◽  
Cardiorespiratory Fitness ◽  
Exercise Intensity ◽  
High Intensity ◽  
Moderate Intensity ◽  
Peak Power Output ◽  
Flow Mediated Dilation ◽  
Elderly Men ◽  
Cycling Exercise ◽  
Vascular Adaptation

Impaired endothelial function is observed with aging and in those with low cardiorespiratory fitness (V̇o2peak). Improvements in endothelial function with exercise training are somewhat dependent on the intensity of exercise. While the acute stimulus for this improvement is not completely understood, it may, in part, be due to the flow-mediated dilation (FMD) response to acute exercise. We examined the hypothesis that exercise intensity alters the brachial (systemic) FMD response in elderly men and is modulated by V̇o2peak. Forty-seven elderly men were stratified into lower (V̇o2peak = 24.3 ± 2.9 ml·kg−1·min−1; n = 27) and higher fit groups (V̇o2peak = 35.4 ± 5.5 ml·kg−1·min−1; n = 20) after a test of cycling peak power output (PPO). In randomized order, participants undertook moderate-intensity continuous exercise (MICE; 40% PPO) or high-intensity interval cycling exercise (HIIE; 70% PPO) or no-exercise control. Brachial FMD was assessed at rest and 10 and 60 min after exercise. FMD increased after MICE in both groups {increase of 0.86% [95% confidence interval (CI), 0.17–1.56], P = 0.01} and normalized after 60 min. In the lower fit group, FMD was reduced after HIIE [reduction of 0.85% (95% CI, 0.12–1.58), P = 0.02] and remained decreased at 60 min. In the higher fit group, FMD was unchanged immediately after HIIE and increased after 60 min [increase of 1.52% (95% CI, 0.41–2.62), P < 0.01, which was correlated with V̇o2peak, r = 0.41; P < 0.01]. In the no-exercise control, FMD was reduced in both groups after 60 min ( P = 0.05). Exercise intensity alters the acute FMD response in elderly men and V̇o2peak modulates the FMD response following HIIE but not MICE. The sustained decrease in FMD in the lower fit group following HIIE may represent a signal for vascular adaptation or endothelial fatigue. NEW & NOTEWORTHY This study is the first to show that moderate-intensity continuous cycling exercise increased flow-mediated dilation (FMD) transiently before normalization of FMD after 1 h, irrespective of cardiorespiratory fitness level in elderly men. Interestingly, we show increased FMD after high-intensity cycling exercise in higher fit men, with a sustained reduction in FMD in lower fit men. The prolonged reduction in FMD after high-intensity cycling exercise may be associated with future vascular adaptation but may also reflect a period of increased cardiovascular risk in lower fit elderly men.

scholarly journals High-intensity exercise and cognitive function in cognitively normal older adults: a pilot randomised clinical trial

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Belinda M. Brown ◽  
Natalie Frost ◽  
Stephanie R. Rainey-Smith ◽  
James Doecke ◽  
Shaun Markovic ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Cardiorespiratory Fitness ◽  
Exercise Intensity ◽  
High Intensity ◽  
Randomised Clinical Trial ◽  
Trial Registration ◽  
Moderate Intensity ◽  
Moderate Intensity Exercise ◽  
Cognitively Normal ◽  
Exercise Interventions

Abstract Background Physical inactivity has been consistently linked to increased risk of cognitive decline; however, studies examining the impact of exercise interventions on cognition have produced inconsistent findings. Some observational studies suggest exercise intensity may be important for inducing cognitive improvements; however, this has yet to be thoroughly examined in older adult cohorts. The objective of the current study was to evaluate the effect of systematically manipulated high-intensity and moderate-intensity exercise interventions on cognition. Methods This multi-arm pilot randomised clinical trial investigated the effects of 6 months of high-intensity exercise and moderate-intensity exercise, compared with an inactive control, on cognition. Outcome measures were assessed at pre- (baseline), post- (6 months), and 12 months post-intervention. Ninety-nine cognitively normal men and women (aged 60–80 years) were enrolled from October 2016 to November 2017. Participants that were allocated to an exercise group (i.e. high-intensity or moderate-intensity) engaged in cycle-based exercise two times per week for 6 months. Cognition was assessed using a comprehensive neuropsychological test battery. Cardiorespiratory fitness was evaluated by a graded exercise test. Results There was a dose-dependent effect of exercise intensity on cardiorespiratory fitness, whereby the high-intensity group experienced greater increases in fitness than the moderate-intensity and control groups. However, there was no direct effect of exercise on cognition. Conclusions We did not observe a direct effect of exercise on cognition. Future work in this field should be appropriately designed and powered to examine factors that may contribute to individual variability in response to intervention. Trial registration This study is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12617000643370). Registered on 3 May 2017—retrospectively registered. https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=372780

Warm-Up Strategy and High-Intensity Endurance Performance in Trained Cyclists

2015 ◽  
Vol 10 (3) ◽  
pp. 353-360 ◽  
Author(s):  
Peter M. Christensen ◽  
Jens Bangsbo
Keyword(s):  
Exercise Intensity ◽  
High Intensity ◽  
Performance Test ◽  
Recovery Period ◽  
Endurance Performance ◽  
Moderate Intensity ◽  
Peak Power Output ◽  
Moderate Intensity Exercise ◽  
Warm Up ◽  
Subsequent Performance

Purpose:To evaluate the influence of warm-up exercise intensity and subsequent recovery on intense endurance performance, selected blood variables, and the oxygen-uptake (VO2) response.Methods:Twelve highly trained male cyclists (VO2max 72.4 ± 8.0 mL · min−1 · kg−1, incremental-test peak power output (iPPO) 432 ± 31 W; mean ± SD) performed 3 warm-up strategies lasting 20 min before a 4-min maximal-performance test (PT). Strategies consisted of moderate-intensity exercise (50%iPPO) followed by 6 min of recovery (MOD6) or progressive high-intensity exercise (10–100%iPPO and 2 × 20-s sprints) followed by recovery for 6 min (HI6) or 20 min (HI20).Results:Before PT venous pH was lower (P < .001) in HI6 (7.27 ± 0.05) than in HI20 (7.34 ± 0.04) and MOD6 (7.35 ± 0.03). At the same time, differences (P < .001) existed for venous lactate in HI6 (8.2 ± 2.0 mmol/L), HI20 (5.1 ± 1.7 mmol/L), and MOD6 (1.4 ± 0.4 mmol/L), as well as for venous bicarbonate in HI6 (19.3 ± 2.6 mmol/L), HI20 (22.6 ± 2.3 mmol/L), and MOD6 (26.0 ± 1.4 mmol/L). Mean power in PT in HI6 (402 ± 38 W) tended to be lower (P = .11) than in HI20 (409 ± 34 W) and was lower (P = .007) than in MOD6 (416 ± 32 W). Total VO2 (15–120 s in PT) was higher in HI6 (8.18 ± 0.86 L) than in HI20 (7.85 ± 0.82 L, P = .008) and MOD6 (7.90 ± 0.74 L, P = .012).Conclusions:Warm-up exercise including race-pace and sprint intervals combined with short recovery can reduce subsequent performance in a 4-min maximal test in highly trained cyclists. Thus, a reduced time at high exercise intensity, a reduced intensity in the warm-up, or an extension of the recovery period after an intense warm-up is advocated.

Effects of Different Intensity Walking on Serum Nitric Oxide for the Elderly Men

2013 ◽  
Vol 641-642 ◽  
pp. 748-751
Author(s):  
Ke Xin Ren
Keyword(s):  
Nitric Oxide ◽  
Cardiovascular Disease ◽  
Exercise Intensity ◽  
High Intensity ◽  
Moderate Intensity ◽  
Oxide Content ◽  
Elderly Men ◽  
Blood Samples ◽  
Low Intensity ◽  
Group Serum

Objective: In order to study the effect of different intensity exercise on serum nitric oxide and nitric oxide synthase of elderly men, and look for the most appropriate exercise intensity for them which can prevent cardiovascular disease. Methods: 36 men who are 55 to 62 years old, were randomly divided into the low intensity group(L group,n=12), the moderate-intensity group(M group,n=12) and the high-intensity group(H group,n=12). During the period for testing, they walked for 12 weeks, 4 times per week, 45 minutes for each time,target heart rate is 100 ~110 beats/min(L group), 110 ~120 beats/min(M group), 120~ 130 beats/min(H group). With an over-night fast, all the subject venous blood samples were drawn by 4ml before and after the exercise. The blood samples were centrifuged and separated immediately, then serum nitric oxide content, TNOS activity, cNOS activity, iNOS activity were measured.Results:In low-intensity group, serum NO content, TNOS activity, cNOS activity were significantly increased than pre-exercise (P<0.05); in moderate-intensity group,serum NO content,TNOS activity,cNOS activity were very significantly increased than pre-exercise (P <0.01);the indicators of high-intensity exercise group did not change significantly. Conclusion: we recommend that a more appropriate exercise intensity is 100-120 beats /min for elderly during fitness exercise, and especially 110-120 beats/min. Such intensity exercise can increase NO content in vivo, thus effectively prevent the occurrence of cardiovascular disease.

scholarly journals Short-Term High-Intensity Interval Training on Body Composition and Blood Glucose in Overweight and Obese Young Women

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Zhaowei Kong ◽  
Shengyan Sun ◽  
Min Liu ◽  
Qingde Shi
Keyword(s):  
Body Composition ◽  
Blood Glucose ◽  
Cardiorespiratory Fitness ◽  
Young Women ◽  
High Intensity ◽  
Interval Training ◽  
Moderate Intensity ◽  
High Intensity Interval Training ◽  
Short Term ◽  
High Intensity Interval

This study was to determine the effects of five-week high-intensity interval training (HIIT) on cardiorespiratory fitness, body composition, blood glucose, and relevant systemic hormones when compared to moderate-intensity continuous training (MICT) in overweight and obese young women.Methods. Eighteen subjects completed 20 sessions of HIIT or MICT for five weeks. HIIT involved 60 × 8 s cycling at ~90% of peak oxygen consumption (V˙O2peak) interspersed with 12 s recovery, whereas MICT involved 40-minute continuous cycling at 65% ofV˙O2peak.V˙O2peak, body composition, blood glucose, and fasting serum hormones, including leptin, growth hormone, testosterone, cortisol, and fibroblast growth factor 21, were measured before and after training.Results. Both exercise groups achieved significant improvements inV˙O2peak(+7.9% in HIIT versus +11.7% in MICT) and peak power output (+13.8% in HIIT versus +21.9% in MICT) despite no training effects on body composition or the relevant systemic hormones. Blood glucose tended to be decreased after the intervention (p=0.062). The rating of perceived exertion in MICT was higher than that in HIIT (p=0.042).Conclusion. Compared with MICT, short-term HIIT is more time-efficient and is perceived as being easier for improving cardiorespiratory fitness and fasting blood glucose for overweight and obese young women.

scholarly journals High-intensity exercise to promote accelerated improvements in cardiorespiratory fitness (HI-PACE): Study protocol for a randomized controlled trial

2019 ◽  
Author(s):  
Joshua E. McGee ◽  
Savanna G. Barefoot ◽  
Nicole R. Gniewek ◽  
Patricia M. Brophy ◽  
Angela Clark ◽  
...  
Keyword(s):  
Public Health ◽  
Type 2 Diabetes ◽  
African Americans ◽  
Aerobic Exercise ◽  
Cardiorespiratory Fitness ◽  
High Intensity ◽  
Controlled Trial ◽  
High Intensity Exercise ◽  
Moderate Intensity

Abstract Background African Americans have a disproportionate prevalence and incidence of type 2 diabetes compared to Caucasians. Recent evidence indicates low cardiorespiratory fitness (CRF) level, an independent risk factor for type 2 diabetes, is also more prevalent in African Americans than Caucasians. Numerous studies in Caucasian populations suggest vigorous exercise intensity may promote greater improvements in CRF and other type 2 diabetes risk factors (e.g. reduction of glucose/insulin levels, pulse wave velocity, body fat, etc.) than moderate intensity. However, current evidence comparing health benefits of different aerobic exercise intensities on type 2 diabetes risk factors in African Americans is negligible. This is clinically important as African Americans have a greater risk for type 2 diabetes and are less likely to meet public health recommendations for physical activity than Caucasians. The purpose of the High-Intensity exercise to Promote Accelerated improvements in CardiorEspiratory fitness (HI-PACE) study is to evaluate whether high-intensity aerobic exercise elicits greater improvements in CRF, insulin action, and arterial stiffness than moderate-intensity exercise in African Americans. Methods/Design­ A randomized controlled trial will be performed on overweight and obese (body mass index: 25-45 kg/m2) African Americans (35-65 years) (n=60). Participants will be randomized to moderate-intensity (MOD-INT) or high-intensity (HIGH-INT) aerobic exercise training, or a non-exercise control group (CON) for 24 weeks. Supervised exercise will be performed at a heart rate associated with 45-55% and 70-80% of VO2 max in the MOD-INT and the HIGH-INT groups, respectively, for an exercise dose of 600 MET-minutes/week (consistent with public health recommendations). The primary outcome is change in CRF. Secondary outcomes include change in insulin sensitivity (measured via an intravenous glucose tolerance test), skeletal muscle mitochondrial oxidative capacity (via near infrared spectroscopy), skeletal muscle measurements (i.e. citrate synthase, COX IV, GLUT-4, CPT-1, PGC1-α), arterial stiffness (via carotid-femoral pulse wave velocity), body fat, C-reactive protein, and psychological outcomes (quality of life/exercise enjoyment). Discussion The anticipated results of the HI-PACE study will provide vital information on the health effects of high-intensity exercise in African Americans. This study will advance health disparity research and has the potential to influence future public health guidelines for physical activity. Trial Registration ClinicalTrials.gov ID: NCT02892331. Registered on 8 September 2016, https://clinicaltrials.gov/ct2/show/NCT02892331

scholarly journals What Doesn't Kill you Makes you Fitter: A Systematic Review of High-Intensity Interval Exercise for Patients with Cardiovascular and Metabolic Diseases

2015 ◽  
Vol 9 ◽  
pp. CMC.S26230 ◽  
Author(s):  
Itamar Levinger ◽  
Christopher S. Shaw ◽  
Nigel K. Stepto ◽  
Samantha Cassar ◽  
Andrew J. McAinch ◽  
...  
Keyword(s):  
Systematic Review ◽  
High Intensity ◽  
Metabolic Diseases ◽  
Moderate Intensity ◽  
Exercise Session ◽  
Peak Power Output ◽  
Moderate Intensity Exercise ◽  
Interval Exercise ◽  
Cardiometabolic Diseases ◽  
High Intensity Interval

High-intensity interval exercise (HIIE) has gained popularity in recent years for patients with cardiovascular and metabolic diseases. Despite potential benefits, concerns remain about the safety of the acute response (during and/or within 24 hours postexercise) to a single session of HIIE for these cohorts. Therefore, the aim of this study was to perform a systematic review to evaluate the safety of acute HIIE for people with cardiometabolic diseases. Electronic databases were searched for studies published prior to January 2015, which reported the acute responses of patients with cardiometabolic diseases to HIIE (≥80% peak power output or ≥85% peak aerobic power, VO2peak). Eleven studies met the inclusion criteria (n = 156; clinically stable, aged 27-66 years), with 13 adverse responses reported (~8% of individuals). The rate of adverse responses is somewhat higher compared to the previously reported risk during moderate-intensity exercise. Caution must be taken when prescribing HIIE to patients with cardiometabolic disease. Patients who wish to perform HIIE should be clinically stable, have had recent exposure to at least regular moderate-intensity exercise, and have appropriate supervision and monitoring during and after the exercise session.

Abstract 14433: High Intensity Exercise Training Safely Increases Cardiorespiratory Fitness in Patients With Hypertrophic Cardiomyopathy

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Katrin A Dias ◽  
James P Macnamara ◽  
Christopher M Hearon ◽  
Mitchel Samels ◽  
Aslan Turer ◽  
...  
Keyword(s):  
Hypertrophic Cardiomyopathy ◽  
Cardiorespiratory Fitness ◽  
High Intensity ◽  
Training Session ◽  
Interval Training ◽  
High Intensity Exercise ◽  
Moderate Intensity ◽  
Moderate Intensity Exercise ◽  
Wide Complex Tachycardia ◽  
High Intensity Interval

Introduction: Patients with hypertrophic cardiomyopathy (HCM) are excluded from high intensity activities due to perceived fear of sudden cardiac death. Observational data from athletes with HCM suggest that engaging in high intensity exercise (HIE) may be safe and is associated with higher cardiorespiratory fitness. Whether HIE can safely elicit a superior increase in fitness compared to moderate intensity exercise in patients with HCM is unclear. Methods: Nine HCM patients (49 ± 7 years, 3 female) were assessed for maximal oxygen uptake (VO 2 max, Douglas Bag method), cardiac output (Q c , acetylene rebreathing), and peripheral oxygen extraction (av-O 2 diff, Fick equation) before randomization and after 5 months of MIE or HIE training. Patients completed 3-4 sessions of MIE each week, while the HIE group also incorporated 1-2 supervised high intensity interval training sessions/week from month 3 onwards. Arrhythmias were monitored via pre-existing implantable cardiac defibrillators or implantable loop recorders placed prior to training. Results: Five months of MIE increased absolute VO 2 max by 3% and relative VO 2 max by 4%, while HIE consistently increased absolute VO 2 max by 6% and relative VO 2 max by 5% (Figure). Maximal Q c did not change after MIE but increased in all HIE patients (+1.2L/min, 95% CI -1.4 to 3.9), while maximal av-O 2 diff remained stable in both groups. Training compliance was 84 ± 15% in HIE and 93 ± 11% in MIE. There were no serious exercise-related adverse events in either group though two HIE subjects had arrhythmias at rest: 1) 14-beat run of wide complex tachycardia of uncertain mechanism given underlying conduction disease prior to a training session, and 2) 11 beats of non-sustained ventricular tachycardia prior to post exercise testing. Conclusions: Preliminary findings show that five months of HIE safely and consistently increased cardiorespiratory fitness in patients with HCM, though overall the improvements were comparable to MIE.

scholarly journals Exercise intensity and the protection from postprandial vascular dysfunction in adolescents

2015 ◽  
Vol 308 (11) ◽  
pp. H1443-H1450 ◽  
Author(s):  
B. Bond ◽  
P. E. Gates ◽  
S. R. Jackman ◽  
L. M. Corless ◽  
C. A. Williams ◽  
...  
Keyword(s):  
Endothelial Function ◽  
Exercise Intensity ◽  
Acute Exercise ◽  
Vascular Dysfunction ◽  
Reactive Hyperemia ◽  
Total Antioxidant Status ◽  
Doppler Imaging ◽  
Moderate Intensity ◽  
Moderate Intensity Exercise ◽  
High Intensity Interval

Acute exercise transiently improves endothelial function and protects the vasculature from the deleterious effects of a high-fat meal (HFM). We sought to identify whether this response is dependent on exercise intensity in adolescents. Twenty adolescents (10 male, 14.3 ± 0.3 yr) completed three 1-day trials: 1) rest (CON); 2) 8 × 1 min cycling at 90% peak power with 75 s recovery [high-intensity interval exercise (HIIE)]; and 3) cycling at 90% of the gas exchange threshold [moderate-intensity exercise (MIE)] 1 h before consuming a HFM (1.50 g/kg fat). Macrovascular and microvascular endothelial function was assessed before and immediately after exercise and 3 h after the HFM by flow-mediated dilation (FMD) and laser Doppler imaging [peak reactive hyperemia (PRH)]. FMD and PRH increased 1 h after HIIE [ P < 0.001, effect size (ES) = 1.20 and P = 0.048, ES = 0.56] but were unchanged after MIE. FMD and PRH were attenuated 3 h after the HFM in CON ( P < 0.001, ES = 1.78 and P = 0.02, ES = 0.59). FMD remained greater 3 h after the HFM in HIIE compared with MIE ( P < 0.001, ES = 1.47) and CON ( P < 0.001, ES = 2.54), and in MIE compared with CON ( P < 0.001, ES = 1.40). Compared with CON, PRH was greater 3 h after the HFM in HIIE ( P = 0.02, ES = 0.71) and MIE ( P = 0.02, ES = 0.84), with no differences between HIIE and MIE ( P = 0.72, ES = 0.16). Plasma triacylglycerol concentration and total antioxidant status concentration were not different between trials. We conclude that exercise intensity plays an important role in protecting the vasculature from the deleterious effects of a HFM. Performing HIIE may provide superior vascular benefits than MIE in adolescent groups.

Comparison of High-Intensity Interval Training to Moderate-Intensity Continuous Training in Older Adults: A Systematic Review

2020 ◽  
Vol 28 (5) ◽  
pp. 798-807
Author(s):  
Christopher J. Keating ◽  
Juan Á. Párraga Montilla ◽  
Pedro Á. Latorre Román ◽  
Rafael Moreno del Castillo
Keyword(s):  
Systematic Review ◽  
Older Adults ◽  
Cardiorespiratory Fitness ◽  
High Intensity ◽  
Interval Training ◽  
Moderate Intensity ◽  
High Intensity Interval Training ◽  
Continuous Training ◽  
Female Population ◽  
High Intensity Interval

High-intensity interval training (HIIT) is emerging as a safe and effective means to combat chronic diseases. The objective of this work was to perform a systematic review of the effect of HIIT interventions in an aging population. Three electronic databases were searched for randomized trials comparing the effect of HIIT and moderate-intensity continuous training in older adults. After a thorough screening process, 15 articles were identified as meeting the inclusion criteria. All studies expressed a comparable or superior effect of HIIT in cardiorespiratory fitness measures. No studies reported a lessened effect of HIIT in comparison with moderate-intensity continuous training. This systematic review demonstrates that HIIT is a useful exercise regimen, which can be used in older adults to increase cardiorespiratory fitness. More research is needed to determine the effects of HIIT in an aging, predominately female population.

Sign in / Sign up

Export Citation Format

Share Document