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

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

10.21203/rs.2.380/v1 ◽

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

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

10.21203/rs.2.380/v2 ◽

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.

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The Effect of a Novel Low-Volume Aerobic Exercise Intervention on Liver Fat in Type 2 Diabetes: A Randomized Controlled Trial

Diabetes Care ◽

10.2337/dc19-2523 ◽

2020 ◽

Vol 43 (10) ◽

pp. 2371-2378

Author(s):

Angelo Sabag ◽

Kimberley L. Way ◽

Rachelle N. Sultana ◽

Shelley E. Keating ◽

James A. Gerofi ◽

...

Keyword(s):

Type 2 Diabetes ◽

Randomized Controlled Trial ◽

Aerobic Exercise ◽

Exercise Intervention ◽

Controlled Trial ◽

Liver Fat ◽

Randomized Controlled ◽

Low Volume

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The Effect of Low-Volume, High-Intensity Interval Training on Blood Glucose Markers, Anthropometric Measurements, and Cardiorespiratory Fitness in Patients with Type 2 Diabetes

Critical Reviews in Physical and Rehabilitation Medicine ◽

10.1615/critrevphysrehabilmed.2015014122 ◽

2015 ◽

Vol 27 (1) ◽

pp. 19-34 ◽

Cited By ~ 3

Author(s):

Michael Curry ◽

Saurabh P Mehta ◽

Justin C. Chaffin ◽

Eric Duran ◽

Brian Washington ◽

...

Keyword(s):

Type 2 Diabetes ◽

Blood Glucose ◽

Cardiorespiratory Fitness ◽

High Intensity ◽

Interval Training ◽

Anthropometric Measurements ◽

High Intensity Interval Training ◽

Low Volume ◽

High Intensity Interval

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Exercise Training Intensity and the Fitness-Fatness Index in Adults with Metabolic Syndrome: A Randomized Trial

Sports Medicine - Open ◽

10.1186/s40798-021-00395-7 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Joyce S. Ramos ◽

Lance C. Dalleck ◽

Mackenzie Fennell ◽

Alex Martini ◽

Talita Welmans ◽

...

Keyword(s):

Type 2 Diabetes ◽

Metabolic Syndrome ◽

Cardiorespiratory Fitness ◽

Mortality Risk ◽

High Volume ◽

Moderate Intensity ◽

Metabolic Equivalents ◽

The Metabolic Syndrome ◽

Low Volume

Abstract Background Cardiorespiratory fitness and fatness (notably central obesity) are mediating factors of the metabolic syndrome (MetS) and consequent cardiovascular disease (CVD)/mortality risk. The fitness-fatness index (FFI) combines these factors and has been reported to be a better indicator of CVD and all-cause mortality risk, beyond the capacity of either fitness or fatness alone. Objective This study sought to investigate the effects of different exercise intensities on FFI in adults with MetS. Methods This was a sub-study of the ‘Exercise in the prevention of Metabolic Syndrome’ (EX-MET) multicentre trial. Ninety-nine adults diagnosed with MetS according to the International Diabetes Federation criteria were randomized to one of the following 16-week exercise interventions: i) moderate-intensity continuous training (MICT) at 60–70% HRpeak for 30 min/session (n = 34, 150 min/week); ii) 4 × 4 min bouts of high-intensity interval training at 85–95% HRpeak, interspersed with 3-min active recovery at 50–70% HRpeak (n = 34, 38 min/session, 114 min/week); and iii) 1 × 4 min bout of HIIT at 85–95% HRpeak (n = 31, 17 min/session, 51 min/week). Cardiorespiratory fitness (peak oxygen uptake, V̇O2peak) was determined via indirect calorimetry during maximal exercise testing and fatness was the ratio of waist circumference-to-height (WtHR). FFI was calculated as V̇O2peak in metabolic equivalents (METs) divided by WtHR. A clinically meaningful response to the exercise intervention was taken as a 1 FFI unit increase. Results Seventy-seven participants completed pre and post testing to determine FFI. While there was no significant between group difference (p = 0.30), there was a small group x time interaction effect on FFI [F(2, 73) = 1.226; η2 = 0.01], with numerically greater improvements following HIIT (4HIIT, + 16%; 1HIIT, + 11%) relative to MICT (+ 7%). There was a greater proportion of participants who had a clinically meaningful change in FFI following high-volume HIIT (60%, 15/25) and low-volume HIIT (65%, 17/26) compared to MICT (38%, 10/26), but with no significant between-group difference (p = 0.12). A similar trend was found when a sub-analysis comparing the FFI between those with type 2 diabetes (MICT, 33%, 3/9; high-volume HIIT, 64%, 7/11; and low-volume HIIT, 58%, 7/12) and without type 2 diabetes (MICT, 41%, 7/17; high-volume HIIT, 57%, 8/14; low-volume HIIT, 71%, 10/14). Conclusion Although there were no statistically significant differences detected between groups, this study suggests that the response to changes in FFI in adults with MetS may be affected by exercise intensity, when numerical differences between exercise groups are considered. Further research is warranted. Trial registration number and date of registration: ClinicalTrials.gov NCT01676870; 31/08/2012.

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Exercise Training Volume and the Fitness-fatness Index in Adults With Metabolic Syndrome: A Randomised Trial

10.21203/rs.3.rs-534159/v1 ◽

2021 ◽

Author(s):

Joyce S. Ramos ◽

Lance C. Dalleck ◽

Mackenzie Fennell ◽

Alex D. Martini ◽

Talita R. Welmans ◽

...

Keyword(s):

Type 2 Diabetes ◽

Metabolic Syndrome ◽

Cardiorespiratory Fitness ◽

Mortality Risk ◽

High Volume ◽

Moderate Intensity ◽

Metabolic Equivalents ◽

The Metabolic Syndrome ◽

Low Volume

Abstract Background Cardiorespiratory fitness and fatness (notably central obesity) are mediating factors of the metabolic syndrome (MetS), and consequent cardiovascular disease (CVD)/mortality risk. The fitness-fatness index (FFI) combines these factors and has been reported to be a better indicator of CVD and all-cause mortality risk, beyond the capacity of either fitness or fatness alone. Objective This study sought to investigate the effects of different exercise volumes on FFI in adults with MetS. Methods This was a sub-study of the ‘Exercise in the prevention of Metabolic Syndrome’ (EX-MET) multicenter trial. Ninety-nine adults diagnosed with MetS according to the International Diabetes Federation criteria were randomized to one of the following 16-week exercise interventions: i) moderate-intensity continuous training (MICT) at 60-70% HRpeak for 30 min/session (n=34, 150 min/week); ii) 4 x 4 min bouts of high-intensity interval training at 85-95% HRpeak, interspersed with 3-min active recovery at 50-70% HRpeak (n=34, 38min/session, 114 mins/week); and iii) 1 x 4 min bout of HIIT at 85-95% HRpeak (n=31, 17 min/session, 51 min/week). Cardiorespiratory fitness (peak oxygen uptake, V̇O2peak) was determined via indirect calorimetry during maximal exercise testing and fatness was the ratio of waist circumference-to-height (WHtR). FFI was calculated as V̇O2peak in metabolic equivalents (METs) divided by WHtR. A clinically meaningful response to the exercise intervention was taken as a 1 FFI unit increase. Results Seventy-seven participants completed pre and post testing to determine FFI. There was a greater proportion of participants who had a clinically meaningful change in FFI following high-volume HIIT (60%, 15/25) and low-volume HIIT (65%, 17/26) compared to MICT (38%, 10/26), but with no significant between-group difference (p=0.12). A similar trend was found when a sub-analysis comparing the FFI between those with type 2 diabetes (MICT, 33%, 3/9; high-volume HIIT, 64%, 7/11; and low-volume HIIT, 58%, 7/12) and without type 2 diabetes (MICT, 41%, 7/17; high-volume HIIT, 57%, 8/14; low-volume HIIT, 71%, 10/14). Conclusion This study suggests that the response to changes in FFI in adults with MetS is affected by aerobic exercise intensity.

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