Effect of the volume and intensity of exercise training on insulin sensitivity

2004 ◽  
Vol 96 (1) ◽  
pp. 101-106 ◽  
Author(s):  
Joseph A. Houmard ◽  
Charles J. Tanner ◽  
Cris A. Slentz ◽  
Brian D. Duscha ◽  
Jennifer S. McCartney ◽  
...  

Physical activity enhances insulin action in obese/overweight individuals. However, the exercise prescription required for the optimal enhancement is not known. The purpose of this study was to test the hypothesis that exercise training consisting of vigorous-intensity activity would enhance insulin sensitivity more substantially than moderate-intensity activity. Sedentary, overweight/obese subjects ( n = 154) were randomly assigned to either control or an exercise group for 6 mo: 1) low-volume/moderate-intensity group [∼12 miles walking/wk at 40–55% peak O2 consumption (V̇o2 peak)], 2) low-volume/high-intensity group (∼12 miles jogging/wk at 65–80% V̇o2 peak), and 3) high-volume/high-intensity group (∼20 miles jogging/wk at 65–80% V̇o2 peak). Training volume (miles/wk) was achieved by exercising ∼115 min/wk (low-volume/high-intensity group) or ∼170 min/wk (low-volume/moderate-intensity and high-volume/high-intensity groups). Insulin action was measured with an insulin sensitivity index (SI) from an intravenous glucose tolerance test. In the control group, there was a decrement ( P < 0.05) in SI. In contrast, all the exercise groups significantly ( P < 0.05) increased SI; the relative increment in the low-volume/moderate-intensity and high-volume/high-intensity groups (∼85%) were greater than in the low-volume/high-intensity group (∼40%). In conclusion, physical activity encompassing a wide range of intensity and volume minimizes the insulin resistance that develops with a sedentary lifestyle. However, an exercise prescription that incorporated ∼170 min of exercise/wk improved insulin sensitivity more substantially than a program utilizing ∼115 min of exercise/wk, regardless of exercise intensity and volume. Total exercise duration should thus be considered when designing training programs with the intent of improving insulin action.

2009 ◽  
Vol 106 (4) ◽  
pp. 1079-1085 ◽  
Author(s):  
Sudip Bajpeyi ◽  
Charles J. Tanner ◽  
Cris A. Slentz ◽  
Brian D. Duscha ◽  
Jennifer S. McCartney ◽  
...  

The purpose of this study was to determine whether exercise prescriptions differing in volume or intensity also differ in their ability to retain insulin sensitivity during an ensuing period of training cessation. Sedentary, overweight/obese subjects were assigned to one of three 8-mo exercise programs: 1) low volume/moderate intensity [equivalent of ∼12 miles/wk, 1,200 kcal/wk at 40–55% peak O2 consumption (V̇o2peak), 200 min exercise/wk], 2) low volume/vigorous intensity (∼12 miles/wk, 1,200 kcal/wk at 65–80% V̇o2peak, 125 min/wk), and 3) high volume/vigorous intensity (∼20 miles/wk, 2,000 kcal/wk at 65–80% V̇o2peak, 200 min/wk). Insulin sensitivity (intravenous glucose tolerance test, SI) was measured when subjects were sedentary and at 16–24 h and 15 days after the final training bout. SI increased with training compared with the sedentary condition ( P ≤ 0.05) at 16–24 h with all of the exercise prescriptions. SI decreased to sedentary, pretraining values after 15 days of training cessation in the low-volume/vigorous-intensity group. In contrast, at 15 days SI was significantly elevated compared with sedentary ( P ≤ 0.05) in the prescriptions utilizing 200 min/wk (low volume/moderate intensity, high volume/vigorous intensity). In the high-volume/vigorous-intensity group, indexes of muscle mitochondrial density followed a pattern paralleling insulin action by being elevated at 15 days compared with pretraining; this trend was not evident in the low-volume/moderate-intensity group. These findings suggest that in overweight/obese subjects a relatively chronic persistence of enhanced insulin action may be obtained with endurance-oriented exercise training; this persistence, however, is dependent on the characteristics of the exercise training performed.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Eduardo Carballeira ◽  
Karla C. Censi ◽  
Ana Maseda ◽  
Rocío López-López ◽  
Laura Lorenzo-López ◽  
...  

AbstractPhysical exercise, when practiced regularly and in adequate doses, is a proven nonpharmacological measure that helps to prevent and reverse noncommunicable diseases, as well as reduce mortality rates from any cause. In general, older adults perform insufficient physical activity and do not meet the doses recommended by the World Health Organization for the improvement of health through physical activity. However, there is little evidence on adequate doses of exercise in older people, especially in those with multimorbidity. Our main aim was to evaluate the effect of a 6-week intervention on health-related outcomes (body composition, hemodynamic and functionality changes) in 24 individuals aged 65 and older with multimorbidity in a randomized controlled trial. The intervention consisted of a very low volume (60 min per week) of low-to-moderate intensity exercise training (perception of effort from 3 to 6 on an 11-point scale). After the intervention, blood pressure was significantly (p = 0.038) reduced in the exercise group (EG), with a higher reduction in men. Furthermore, the EG decreased their waist circumference (p = 0.005), a proxy of abdominal adiposity, and demonstrated an increased likelihood (73%) that a randomly selected change in muscle mass score from the EG would be greater than a randomly selected change score from the control group. The exercise intervention was particularly effective in enhancing the functionality of older adults with multimorbidity, especially in walking speed and balance skills. Perceptually regulated intensity during exercise training seemed to be a very interesting strategy to train individuals with low physical fitness and comorbidities. This study is registered with Clinicaltrials.gov (NCT 04842396).


2021 ◽  
Author(s):  
Mohammad Soltani ◽  
Masoud Jokar Baluchi ◽  
Daniel Boullosa ◽  
Ali Daraei ◽  
Karuppasamy Govindasamy ◽  
...  

Abstract Background: The current study investigated the chronic effects of high-volume moderate-intensity training and low-volume high-intensity training on heart rate variability (HRV) and arterial stiffness in sedentary adult men. Materials and methods: Forty-five males (age: 42± 5.7 yrs.) were randomly assigned into control group (n=15), high-volume moderate-intensity training (HVMIT) (n=15), and low-volume high-intensity training (LVHIT) (n=15). The HVMIT group ran three times per week, on the treadmill at 50% to 60% of VO2max for 45 to 60 minutes, while the LVHIT trained at 70% to 85% of VO2max for 25 to 40 minutes. Both training programs were equated by caloric expenditure. HRV, Pulse Wave Velocity (PWV), hemodynamic variables, and body composition were measured before and after 12 weeks.Results: Both protocols (HVMIT and LVHIT) significantly increased the Standard deviation of NN intervals (SDNN) and High-frequency (HF) bands after 12 weeks (p ˂ 0.05). The LF/HF ratio decreased significantly in both training groups (p ˂ 0.05). However, these changes were significantly greater in the LVHIT protocol (p ˂ 0.05). Furthermore, the Root mean square of successive RR interval differences (RMSSD) significantly increased only in the LVHIT protocol (P ˂ 0.05). Moreover, a significant decrease in low-frequency (LF) and PWV was only observed following the LVHIT protocol (P ˂ 0.05). Conclusion: This study indicates that the LVHIT protocol is more effective and efficient for improving HRV variables and PWV than the HVMIT protocol.


Author(s):  
Joyce S. Ramos ◽  
Lance C. Dalleck ◽  
Caitlin E. Keith ◽  
Mackenzie Fennell ◽  
Zoe Lee ◽  
...  

Insulin resistance is a central mediating factor of the metabolic syndrome (MetS), with exercise training and metformin proven antidotes to insulin resistance. However, when the two therapies are combined there is conflicting data regarding whether metformin blunts or improves exercise training-induced adaptations. The volume of exercise (duration, intensity, and frequency) on the interaction of exercise training and metformin has yet to be investigated. The aim of this study is therefore to explore the impact of a combination of different exercise volumes and metformin on MetS severity. This is a secondary analysis of data from one of the sites of the ‘Exercise in Prevention of Metabolic Syndrome’ (EX-MET) study. Ninety-nine adults with MetS were randomized into a 16-week exercise program completing either: (i) moderate-intensity continuous training (MICT) at 60–70% of peak heart rate (HRpeak) for 30 min/session (n = 34, 150 min/week); (ii) high-volume high-intensity interval training (HIIT) consisting of 4 × 4 min bouts at 85–95% HRpeak, interspersed with 3 min of active recovery at 50–70% HRpeak (n = 34, 38 min/session, 114 min/week); or (iii) low volume HIIT, 1 × 4 min bout of HIIT at 85–95% HRpeak (n = 31, 17 min/session, 51 min/week). Metformin intake was monitored and recorded throughout the trial. MetS severity was calculated as z-scores derived from MetS risk factors assessed at pre- and post-intervention. Sixty-five participants had complete pre- and post-intervention data for MetS z-score, of which 18 participants (28%) were taking metformin. Over the 16-week intervention, a similar proportion of participants clinically improved MetS severity (Δ ≥ −0.87) with metformin (8/18, 44%) or without metformin (23/47, 49%) (p = 0.75). While there were no between-group differences (p = 0.24), in those who did not take metformin low-volume HIIT had more likely responders (10/15, 67%) compared to MICT (6/16, 38%) and high-volume HIIT (7/16, 44%). In those taking metformin, there was a lower proportion of participants who clinically improved MetS severity following high-volume HIIT (1/6, 17%) compared to MICT (2/4, 50%) and low-volume HIIT (5/8, 63%), but with no between-group difference (p = 0.23). Moreover, in those who performed high-volume HIIT, there was a statistically significantly higher proportion (p = 0.03) of likely non-responders with improved MetS severity in participants taking metformin (4/6, 67%) compared to those not taking metformin (3/16, 19%). In individuals with MetS, the effect of high volume HIIT on MetS severity may be blunted in those taking metformin. These findings need to be confirmed in a larger study.


Healthcare ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 637
Author(s):  
Shengyan Sun ◽  
Zhaowei Kong ◽  
Qingde Shi ◽  
Haifeng Zhang ◽  
On-Kei Lei ◽  
...  

Objective: The purpose of this study was to evaluate the effects of a 4-week low-carbohydrate diet (LC) with or without exercise training on cardiometabolic health-related profiles in overweight/obese women. Methods: Fifty overweight/obese Chinese women (age: 22.2 ± 3.3 years, body mass index (BMI): 25.1 ± 3.1 kg·m−2) were randomized to either a LC control group (LC-CON, n = 16), a LC and high-intensity interval training group (LC-HIIT, n = 17), or a LC and moderate-intensity continuous training group (LC-MICT, n = 17). All groups consumed LC for 4 weeks, while the LC-HIIT and LC-MICT groups followed an additional five sessions of HIIT (10 × 6 s cycling sprints and 9 s rest intervals, 2.5 min in total) or MICT (cycling continuously at 50–60% of peak oxygen uptake (VO2peak) for 30 min) weekly. Blood pressure, fasting glucose, insulin sensitivity, and several metabolic or appetite regulating hormones were measured before and after intervention. Results: Significant reductions in body weight (− ~2.5 kg, p < 0.001, η2 = 0.772) and BMI (− ~1 unit, p < 0.001, η2 = 0.782) were found in all groups. Systolic blood pressure was reduced by 5–6 mmHg (p < 0.001, η2 = 0.370); fasting insulin, leptin, and ghrelin levels were also significantly decreased (p < 0.05), while insulin sensitivity was improved. However, there were no significant changes in fasting glucose, glucagon, and gastric inhibitory peptide levels. Furthermore, no group differences were found among the three groups, suggesting that extra training (i.e., LC-HIIT and LC-MICT) failed to trigger additional effects on these cardiometabolic profiles. Conclusions: The short-term carbohydrate restriction diet caused significant weight loss and improved blood pressure and insulin sensitivity in the overweight/obese women, although the combination with exercise training had no additional benefits on the examined cardiometabolic profiles. Moreover, the long-term safety and effectiveness of LC needs further study.


2014 ◽  
Vol 39 (3) ◽  
pp. 409-412 ◽  
Author(s):  
Jenna B. Gillen ◽  
Martin J. Gibala

Growing research suggests that high-intensity interval training (HIIT) is a time-efficient exercise strategy to improve cardiorespiratory and metabolic health. “All out” HIIT models such as Wingate-type exercise are particularly effective, but this type of training may not be safe, tolerable or practical for many individuals. Recent studies, however, have revealed the potential for other models of HIIT, which may be more feasible but are still time-efficient, to stimulate adaptations similar to more demanding low-volume HIIT models and high-volume endurance-type training. As little as 3 HIIT sessions per week, involving ≤10 min of intense exercise within a time commitment of ≤30 min per session, including warm-up, recovery between intervals and cool down, has been shown to improve aerobic capacity, skeletal muscle oxidative capacity, exercise tolerance and markers of disease risk after only a few weeks in both healthy individuals and people with cardiometabolic disorders. Additional research is warranted, as studies conducted have been relatively short-term, with a limited number of measurements performed on small groups of subjects. However, given that “lack of time” remains one of the most commonly cited barriers to regular exercise participation, low-volume HIIT is a time-efficient exercise strategy that warrants consideration by health practitioners and fitness professionals.


2003 ◽  
Vol 62 (3) ◽  
pp. 645-650 ◽  
Author(s):  
Klaas R. Westerterp

Activity intensity is a potential determinant of activity-induced energy expenditure. Tri-axial accelerometery is the most objective measurement technique for the assessment of activity intensity, in combination with doubly-labelled water for the measurement of energy expenditure under free-living conditions. Data on the effects of subject characteristics, including body size and age, and exercise training on the relationship between activity intensity and daily energy expenditure are reviewed. Average daily metabolic rate and non-basal energy expenditure are positively related to body size. The duration and intensity of physical activities do not need to be equivalent to the energy spent on activity. Obese subjects spend more energy on physical activity but can perform fewer activities, especially high-intensity (weight-bearing) activities, because of their higher body weight. Physical activity generally declines gradually from about 60 years of age onwards. Most subjects >80 years have an activity level well below the level defined for sedentary middle-aged adults. Spending relatively more time on low-intensity activities has a negative effect on the mean physical activity level. To obtain a higher physical activity level does not necessarily imply high-intensity activities. In an average subject 25% of the activity-induced energy expenditure may be attributed to high-intensity activities. Exercise training, as a form of high-intensity activity, affects the physical activity level more in younger subjects than in elderly subjects.


2021 ◽  
Vol 478 (21) ◽  
pp. 3827-3846
Author(s):  
Erik A. Richter ◽  
Lykke Sylow ◽  
Mark Hargreaves

The interaction between insulin and exercise is an example of balancing and modifying the effects of two opposing metabolic regulatory forces under varying conditions. While insulin is secreted after food intake and is the primary hormone increasing glucose storage as glycogen and fatty acid storage as triglycerides, exercise is a condition where fuel stores need to be mobilized and oxidized. Thus, during physical activity the fuel storage effects of insulin need to be suppressed. This is done primarily by inhibiting insulin secretion during exercise as well as activating local and systemic fuel mobilizing processes. In contrast, following exercise there is a need for refilling the fuel depots mobilized during exercise, particularly the glycogen stores in muscle. This process is facilitated by an increase in insulin sensitivity of the muscles previously engaged in physical activity which directs glucose to glycogen resynthesis. In physically trained individuals, insulin sensitivity is also higher than in untrained individuals due to adaptations in the vasculature, skeletal muscle and adipose tissue. In this paper, we review the interactions between insulin and exercise during and after exercise, as well as the effects of regular exercise training on insulin action.


2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Rhiannon Kate Patten ◽  
Luke McIlvenna ◽  
Alba Moreno-Asso ◽  
Nigel Nigel Stepto ◽  
Danielle Hiam

Abstract Polycystic ovary syndrome (PCOS) is a common and complex endocrinopathy with reproductive and metabolic manifestations, carrying a major health and economic burden. Exercise training has consistently been found improve clinical outcomes in women with PCOS, but shortfalls with exercise prescription are evident. Research suggests that high intensity intermittent exercise (HIIT) is feasible, well tolerated and enjoyable for people with or at risk of chronic disease and can address many of the shortfalls and barriers to exercise participation. To investigate the effects of high intensity exercise, twenty-four reproductive aged, overweight and obese, previously sedentary women with PCOS were recruited from the community and randomised to complete either 12 weeks of moderate intensity continuous cycling exercise (MOD; 50-60% of maximal heart rate [HRmax]; n=11) or HIIT (90-95% HRmax; n=13). All exercise was supervised by an exercise physiologist and completed 3 times per week on a cycle ergometer. Baseline and post testing measures consisted of peak oxygen consumption (VO2peak) determine by a graded maximal exercise test, insulin sensitivity determined by hyperinsulinaemic-euglycaemic clamp, body composition outcomes and anti-mullerian hormone (AMH). Enjoyment was also measured throughout the intervention using feeling scales. Significant improvements were seen for VO2peak after HIIT with an average increase of 5.6 ± 2.5 mL.kg-1.min-1 (P=0.013) and non-significant increases in the MOD group (3.4 ± 2.1 mL/kg/min; P=0.20). Body composition, fasting insulin and AMH values remained unchanged in both groups. Non-significant improvements in glucose infusion rate (3.3 ± 2.8 mg.lbmkg-1.min-1; P=0.06) and insulin sensitivity index (M-to-I ratio; 3.0 ± 3.8 mg.lbmkg-1.min-1[mU/I]-1 x 100; P=0.17) were found as a result of HIIT compared to no changes after moderate intensity exercise. Importantly, HIIT was also found to be more enjoyable than moderate intensity continuous exercise. The present study is the first to compare current exercise recommendations of moderate and vigorous intensities in women with PCOS. The results of this study provide preliminary validation of HIIT and should be considered for improving cardio-metabolic health in women with PCOS.


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