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

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

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The effect of a novel low-volume aerobic exercise intervention on liver fat in type 2 diabetes: a randomised controlled trial

10.2337/figshare.12621983 ◽

2020 ◽

Author(s):

Angelo Sabag ◽

Kimberley L. Way ◽

Rachelle N. Sultana ◽

Shelley E. Keating ◽

James A. Gerofi ◽

...

Keyword(s):

Type 2 Diabetes ◽

Cardiorespiratory Fitness ◽

High Intensity ◽

Exercise Intervention ◽

Controlled Trial ◽

Liver Fat ◽

Moderate Intensity ◽

Resonance Spectroscopy ◽

Low Volume

Objective: The aim of this study was to examine the effect of a novel low-volume high-intensity interval training (HIIT), moderate-intensity continuous training (MICT) or placebo (PLA) intervention on liver fat, glycaemia, and cardiorespiratory fitness using a randomised placebo-controlled design. Research design and methods: Thirty-five inactive adults (54.6±1.4 years, 54% male; BMI 35.9±0.9kg/m2) with obesity and type 2 diabetes were randomised to 12 weeks of supervised: MICT (n=12) at 60% VO2peak for 45 minutes, 3 days/week, HIIT (n=12) at 90% VO2peak for 4 minutes, 3 days/week, or PLA (n=11). Liver fat % was quantified via proton magnetic resonance spectroscopy. Results: Liver fat reduced in MICT (-0.9±0.7%) and HIIT (-1.7±1.1%) but increased in PLA (1.2±0.5%) (p = 0.046). HbA1c improved in MICT (-0.3±0.3%) and in HIIT (-0.3±0.3%) but not in PLA (0.5±0.2%) (p=0.014). Cardiorespiratory fitness improved in MICT (2.3±1.2 ml/kg/min) and HIIT (1.1±0.5 ml/kg/min) but not in PLA (-1.5±0.9 ml/kg/min) (p=0.006). Conclusions: MICT or a low-volume HIIT approach involving 12 minutes of weekly high-intensity exercise may improve liver fat, glycaemia, and cardiorespiratory fitness in type 2 diabetes in the absence of weight loss. Further studies are required to elucidate the relationship between exercise-induced reductions in liver fat and improvements in glycaemia.

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The effect of a novel low-volume aerobic exercise intervention on liver fat in type 2 diabetes: a randomised controlled trial

10.2337/figshare.12621983.v1 ◽

2020 ◽

Author(s):

Angelo Sabag ◽

Kimberley L. Way ◽

Rachelle N. Sultana ◽

Shelley E. Keating ◽

James A. Gerofi ◽

...

Keyword(s):

Type 2 Diabetes ◽

Cardiorespiratory Fitness ◽

High Intensity ◽

Exercise Intervention ◽

Controlled Trial ◽

Liver Fat ◽

Moderate Intensity ◽

Resonance Spectroscopy ◽

Low Volume

Objective: The aim of this study was to examine the effect of a novel low-volume high-intensity interval training (HIIT), moderate-intensity continuous training (MICT) or placebo (PLA) intervention on liver fat, glycaemia, and cardiorespiratory fitness using a randomised placebo-controlled design. Research design and methods: Thirty-five inactive adults (54.6±1.4 years, 54% male; BMI 35.9±0.9kg/m2) with obesity and type 2 diabetes were randomised to 12 weeks of supervised: MICT (n=12) at 60% VO2peak for 45 minutes, 3 days/week, HIIT (n=12) at 90% VO2peak for 4 minutes, 3 days/week, or PLA (n=11). Liver fat % was quantified via proton magnetic resonance spectroscopy. Results: Liver fat reduced in MICT (-0.9±0.7%) and HIIT (-1.7±1.1%) but increased in PLA (1.2±0.5%) (p = 0.046). HbA1c improved in MICT (-0.3±0.3%) and in HIIT (-0.3±0.3%) but not in PLA (0.5±0.2%) (p=0.014). Cardiorespiratory fitness improved in MICT (2.3±1.2 ml/kg/min) and HIIT (1.1±0.5 ml/kg/min) but not in PLA (-1.5±0.9 ml/kg/min) (p=0.006). Conclusions: MICT or a low-volume HIIT approach involving 12 minutes of weekly high-intensity exercise may improve liver fat, glycaemia, and cardiorespiratory fitness in type 2 diabetes in the absence of weight loss. Further studies are required to elucidate the relationship between exercise-induced reductions in liver fat and improvements in glycaemia.

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Continuous low- to moderate-intensity exercise training is as effective as moderate- to high-intensity exercise training at lowering blood HbA1c in obese type 2 diabetes patients

Diabetologia ◽

10.1007/s00125-009-1354-3 ◽

2009 ◽

Vol 52 (9) ◽

pp. 1789-1797 ◽

Cited By ~ 92

Author(s):

D. Hansen ◽

P. Dendale ◽

R. A. M. Jonkers ◽

M. Beelen ◽

R. J. F. Manders ◽

...

Keyword(s):

Type 2 Diabetes ◽

Exercise Training ◽

High Intensity ◽

High Intensity Exercise ◽

Moderate Intensity ◽

Moderate Intensity Exercise ◽

Diabetes Patients

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Exercise Intensities as Factors of Metabolic Outcomes in Type 2 Diabetes: A Systematic Review

Home Health Care Management & Practice ◽

10.1177/1084822318815446 ◽

2018 ◽

Vol 31 (3) ◽

pp. 193-203

Author(s):

Elizabeth Moxley ◽

Tory Bugaieski

Keyword(s):

Type 2 Diabetes ◽

High Intensity ◽

Fasting Glucose ◽

High Intensity Exercise ◽

Systemic Review ◽

Moderate Intensity ◽

Low Intensity ◽

Metabolic Outcomes ◽

Low Intensity Exercise

Exercise is effective to prevent and treat type 2 diabetes, although currently underutilized. This review analyzes the metabolic response to exercise performance at various intensities in individuals with type 2 diabetes. These findings provide insight into the development of safe and efficacious exercise prescriptions and education. We conducted a systemic review of the literature to examine the association of various exercise protocols with metabolic outcomes in type 2 diabetes. Between 1984 and 2018, 29 studies were categorized per exercise mode and intensity levels according to the American College of Sports Medicine standards. The most consistent improvement was found in HbA1c following moderate- to high-intensity exercise—post-exercise fasting glucose improved to a lesser extent. Low-intensity exercise improved HOMA-IR (homeostasis model assessment for insulin resistance) levels. Glucose and HbA1c improved most following interval compared with continuous exercise, irrespective of intensity. A comparison of high-intensity exercise with moderate-intensity exercise demonstrated few differences in HbA1c, fasting glucose, fasting insulin, and HOMA-IR. Irrespective of exercise intensity, HbA1c improvements were observed, suggesting a delayed progression to diabetes-related complications. Initial low-intensity exercise, with increased quantities when feasible, will contribute to metabolic improvements. The variability in methodology and measurement contributed to inconsistent outcomes; additional research with larger samples sizes is warranted.

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Efficacy and Safety of Switching from Low-Dose Statin to High-Intensity Statin for Primary Prevention in Type 2 Diabetes: A Randomized Controlled Trial

Diabetes Metabolic Syndrome and Obesity Targets and Therapy ◽

10.2147/dmso.s219496 ◽

2020 ◽

Vol Volume 13 ◽

pp. 423-431 ◽

Cited By ~ 1

Author(s):

Nuntakorn Thongtang ◽

Jirasak Piyapromdee ◽

Natthakan Tangkittikasem ◽

Kittichai Samaithongcharoen ◽

Nithiwat Srikanchanawat ◽

...

Keyword(s):

Type 2 Diabetes ◽

Randomized Controlled Trial ◽

Primary Prevention ◽

High Intensity ◽

Low Dose ◽

Controlled Trial ◽

Efficacy And Safety ◽

Randomized Controlled

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Functional high-intensity exercise training ameliorates insulin resistance and cardiometabolic risk factors in type 2 diabetes

Experimental Physiology ◽

10.1113/ep086844 ◽

2018 ◽

Vol 103 (7) ◽

pp. 985-994 ◽

Cited By ~ 14

Author(s):

Ciarán E. Fealy ◽

Stephan Nieuwoudt ◽

Julie A. Foucher ◽

Amanda R. Scelsi ◽

Steven K. Malin ◽

...

Keyword(s):

Risk Factors ◽

Insulin Resistance ◽

Type 2 Diabetes ◽

Exercise Training ◽

High Intensity ◽

Cardiometabolic Risk ◽

High Intensity Exercise ◽

Cardiometabolic Risk Factors

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

Circulation ◽

10.1161/circ.142.suppl_3.14433 ◽

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.

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