Impact of post-meal and one-time daily exercise in patient with type 2 diabetes mellitus: a randomized crossover study

DASH diet vs. DASH diet plus physical activity in older patients with type 2 diabetes and high blood pressure: A randomized clinical trial

BACKGROUND AND AIMS

To evaluate the effect of lifestyle modification by adopting a DASH diet, with and without physical activity guidance, on blood pressure, glycemic control, lipid profile, weight, and body composition in older patients with type 2 diabetes mellitus (T2DM) and hypertension.

METHODS AND RESULTS

For this randomized clinical trial, we recruited patients aged 60 years or older with T2DM and uncontrolled hypertension. One group (DASH) received only DASH dietary guidance, while the other group (DASHPED) received dietary guidance and encouragement to walk with a pedometer. Outcomes of interest were (1) blood pressure, (2) physical activity, (3) weight, body mass index (BMI), and body composition, and (4) biochemical variables. Measurements were taken at baseline and 16 weeks after the intervention. We included 35 patients in the analysis. At the end of the study, the DASHPED group had an mean increase in physical activity of 1721 steps/day. Both groups displayed significantly reduced weight, BMI, and waking diastolic pressures on ambulatory blood pressure monitoring after the intervention. A trend of reduced sleeping diastolic pressure was found in the DASHPED group. Changes in weight, BMI, muscle mass, body fat, waist-hip ratio, glycemic control, lipid profile, and insulin sensitivity did not differ between the groups.

CONCLUSION

There was no difference in outcomes between the group that only dieted and the group that also performed increased physical activity, despite a significant increase in exercise. This reinforces the importance of dietary changes in immediate blood pressure control.

Diagnosis to Delivery: A Randomized Clinical Trial of Postmeal Walking in Women with Gestational Diabetes

PURPOSE

The aim of this study was to determine whether advice to perform postmeal walking could be an effective and feasible alternate to standard care continuous walking for the management of gestational diabetes (GDM).

METHODS

Forty women with GDM were randomized between 28 and 30 wk of gestation into either standard care (CTL; 30-min continuous walking, most days per week) or standard care with advice to PMW (daily 10-min walks after three main meals) for ~7 wk. The primary outcome for this randomized controlled trial was postprandial glucose assessed by continuous glucose monitors. Continuous glucose monitor and ActivPAL inclinometers (physical activity parameters) were each worn for 7 d at ~28 and ~35 wk gestation. Delivery outcomes were also collected. A linear mixed model compared the changes across time between groups.

RESULTS

Twenty-six women (PMW: n = 12, CTL: n = 14; age 34 ± 5 y) completed the trial. Mean 3 h postprandial glucose at dinner was higher in the PMW versus CTL group at baseline and across the intervention (main effect group, P = 0.04). Twenty-four hours, nocturnal, and fasting glucose were similar between groups. The PMW group spent ~57 min·d -1 more time sedentary and ~11 min·d -1 less time stepping versus CTL (main effect group: P = 0.02 and 0.05). Adherence to the prescribed 30 min·d -1 of physical activity was high, regardless of whether accumulated as 3 × 10-min or one single bout of walking.

CONCLUSIONS

Distributing activity as 10-min bouts after main meals did not improve postprandial glucose outcomes compared with standard-care control. More research on the optimal duration and intensity of postmeal walks to improve postprandial responses are needed. Strategies that mitigate sedentary time and increase the minutes of physical activity accumulated across the day in pregnancy are also warranted.

Multimodal digital phenotyping of diet, physical activity, and glycemia in Hispanic/Latino adults with or at risk of type 2 diabetes

Digital phenotyping refers to characterizing human bio-behavior through wearables, personal devices, and digital health technologies. Digital phenotyping in populations facing a disproportionate burden of type 2 diabetes (T2D) and health disparities continues to lag compared to other populations. Here, we report our study demonstrating the application of multimodal digital phenotyping, i.e., the simultaneous use of CGM, physical activity monitors, and meal tracking in Hispanic/Latino individuals with or at risk of T2D. For 14 days, 36 Hispanic/Latino adults (28 female, 14 with non-insulin treated T2D) wore a continuous glucose monitor (CGM) and a physical activity monitor (Actigraph) while simultaneously logging meals using the MyFitnessPal app. We model meal events and daily digital biomarkers representing diet, physical activity choices, and corresponding glycemic response. We develop a digital biomarker for meal events that differentiates meal events into normal and elevated categories. We examine the contribution of daily digital biomarkers of elevated meal event count and step count on daily time-in-range 54-140 mg/dL (TIR54-140) and average glucose. After adjusting for step count, a change in elevated meal event count from zero to two decreases TIR54-140 by 4.0% (p = 0.003). An increase in 1000 steps in post-meal step count also reduces the meal event glucose response by 641 min mg/dL (p = 0.0006) and reduces the odds of an elevated meal event by 55% (p < 0.0001). The proposed meal event digital biomarkers may provide an opportunity for non-pharmacologic interventions for Hispanic/Latino adults facing a disproportionate burden of T2D.

After Dinner Rest a While, After Supper Walk a Mile? A Systematic Review with Meta-analysis on the Acute Postprandial Glycemic Response to Exercise Before and After Meal Ingestion in Healthy Subjects and Patients with Impaired Glucose Tolerance

BACKGROUND

The most effective way to cope with high blood sugar spikes is to engage in physical activity in temporal proximity to food intake. However, so far, it is unclear as to whether there is an optimal time for physical activity around food intake.

OBJECTIVES

We aimed to identify the impact of pre- and post-meal exercise on postprandial glucose excursions in humans with and without type 2 diabetes mellitus.

METHODS

We conducted a systematic review with meta-analysis, PROSPERO registration number: CRD42022324070. We screened MEDLINE/PubMed, Cochrane/CINAHL/EMBASE, and Web of Knowledge until 1 May, 2022. We used the risk of bias rating with the crossover extension of the Cochrane risk of bias assessment tool II. Standardized mean differences (SMDs, Hedges' g) with 95% confidence intervals (CIs) were calculated as pooled effect estimates of a random-effects meta-analysis. Eligibility criteria included three-armed randomized controlled trials comparing the acute effects of pre- and post-meal exercise to a no-exercise control in humans.

RESULTS

Eight randomized controlled trials (crossover trials, high risk of bias) with 30 interventions in 116 participants (47 diagnosed with type 2 diabetes, 69 without type 2 diabetes) were eligible. Exercise after meal ingestion (real food or meal replacement drinks) led to a reduction in postprandial glucose excursions compared with exercise before eating (15 effect sizes; SMD = 0.47 [95% CI 0.23, 0.70]) and an inactive control condition (15 effect sizes; SMD = 0.55 [95% CI 0.34, 0.75]. Pre-meal exercise did not lead to significantly lower postprandial glucose compared to an inactive control (15 effect sizes; SMD =  - 0.13 [95% CI - 0.42, 0.17]). The time between meal and exercise (estimate =  - 0.0151; standard error = 0.00473; Z =  - 3.19; p = 0.001; 95% CI - 0.024, - 0.006) had a moderating influence on postprandial glucose excursions.

CONCLUSIONS

Exercise, i.e., walking, has a greater acute beneficial impact on postprandial hyperglycemia when undertaken as soon as possible after a meal rather than after a longer interval or before eating.

CLINICAL TRIAL REGISTRATION

The review was pre-registered in the PROSPERO database (CRD42022324070). The date of submission was 07.04.2022, with the registration on 08.05.2022.

Effects of accumulated versus continuous individualized exercise on postprandial glycemia in young adults with obesity

BACKGROUND

Elevated postprandial glucose (PPG) is an independent risk factor for cardiovascular disease. Post-meal exercise effectively reduces PPG concentrations. However, the effect of accumulated versus continuous post-meal exercise on PPG control remains unclear. This study aimed to investigate the effects of individualized accumulated or continuous exercise on PPG in young adults with obesity.

METHODS

Twenty young adults with obesity (11 males) completed three 4-h randomized crossover trials with 6-14-day washout periods: (1) sitting (SIT), (2) one 30-min walking bout (CONT), and (3) three 10-min walking bouts separated by 20-min resting (ACCU). Walking was initiated 20 min before individual PPG peak after breakfast, which was predetermined by continuous glucose monitoring. Blood samples were collected at 15-30 min intervals, and the 24-h glucose was monitored via continuous glucose monitoring.

RESULTS

The 4-h PPG incremental area under the curve (iAUC) was 12.1%±30.9% and 21.5%±21.5% smaller after CONT (P = 0.022) and ACCU (P < 0.001), respectively, than after SIT. PPG concentrations were lower during CONT at 30-60 min and during ACCU at 30-105 min after breakfast than during SIT (all P < 0.05). The 4-h plasma insulin and C-peptide iAUC, and mean amplitude of glycemic excursions were lower after CONT and ACCU than after SIT (all P < 0.05).

CONCLUSIONS

Both continuous and accumulated exercises reduced PPG, insulin, and C-peptide concentrations and improved glucose fluctuations. Accumulated exercise maintained lower PPG concentrations for a longer time than continuous exercise in young adults with obesity.

CLINICAL TRIAL INFORMATION

Clinical trial registration No. ChiCTR 2000035064, URL: http://www.chictr.org.cn/showproj.aspx?proj=56584; (registered July 29, 2020).HIGHLIGHTS Both continuous and accumulated walking lowered post-meal glucose, insulin and C-peptide levels and improved glucose fluctuation.Postprandial glucose was kept lower for a longer time in accumulated than continuous walking.Accumulated post-meal exercise (e.g. three 10-min bouts of walking) could be recommended as a feasible and practical alternative protocol for postprandial glucose control, especially for those who have difficulty performing sufficient exercise in one session.

Three short postmeal walks as an alternate therapy to continuous walking for women with gestational diabetes

The purpose of this study was to determine whether postmeal walking (breaking up exercise into short bouts after meals) is an effective and feasible alternate to continuous walking for the management of gestational diabetes. Forty-one women with gestational diabetes were randomised between wk 28-30 gestation to either standard-care (30-min continuous exercise) or standard-care with postmeal walking (10-min of walking after breakfast, lunch and dinner). Continuous glucose and activity monitors were worn to measure glycaemic control and adherence during three-days of standard-care (baseline) followed by three-days of postmeal or continuous walking. A linear mixed model analysed the changes from baseline between postmeal and continuous walking, as an average of the three-day periods. Thirty-two women (postmeal walking n=17: control n=15, 33±5 y, body mass index 25±4 kg.m2) completed the trial. Postprandial and overnight glucose concentrations were similar between postmeal walking and control, both interventions improved from baseline. There was no difference in adherence between groups, however postmeal walking completed more minutes of prescribed physical activity across baseline and intervention days compared to the continuous walking standard-care group. Preliminary findings from this proof-of-concept study suggest postmeal walking could be a promising alternative to, and work interchangeably with, traditional advice to perform continuous moderate-intensity physical activity, in women with gestational diabetes. Novelty bullets -Three ten-minute postmeal walks may be comparable to thirty minutes continuous walking for glucose control in women with gestational diabetes - Accumulating activity in short bouts after meals is a feasible alternate to continuous exercise for women with gestational diabetes.

The Effects of Accumulated Versus Continuous Exercise on Postprandial Glycemia, Insulin, and Triglycerides in Adults with or Without Diabetes: A Systematic Review and Meta-Analysis

BACKGROUND

Postprandial dysmetabolism, an important cardiovascular disease risk factor, can be improved by exercise. Further systematic review and meta-analysis is needed to compare the effects of accumulated exercise with a single session of energy-matched continuous exercise on postprandial glucose (PPG), insulin, and triglycerides in adults with or without diabetes.

METHODS

Eight electronic databases were searched on August 28, 2020, and updated on April 27, 2021. Eligible studies were randomized, quasi-randomized, or non-randomized controlled or crossover trials that evaluated the acute or longitudinal effects of accumulated exercise compared with a single session of energy-matched continuous exercise on PPG, postprandial insulin, and triglycerides in diabetic and non-diabetic adults. Same-day and second-morning effects were assessed separately for acute intervention studies. Subgroup analyses were conducted based on the number of exercise bouts (2-3 bouts or frequent brief bouts (e.g., 1-6 min) throughout the day at 20-60-min intervals (known as physical activity [PA] breaks, ≥ 5 bouts)), exercise intensity, and populations. Risk of bias was assessed using the revised Cochrane risk-of-bias tool for randomized trials. Pooled effects were reported as standardized mean differences (SMD) and 95% CI using a random effects model.

RESULTS

Twenty-seven studies (635 participants) were included. A significant difference was found for same-day PPG control, which favored accumulated exercise over one bout of energy-matched continuous exercise (SMD - 0.36 [95%CI: (- 0.56, - 0.17)], P = 0.0002, I2 = 1%), specifically in accumulated exercise with PA breaks (SMD - 0.36 [95%CI: (- 0.64, - 0.08)], P = 0.01, I2 = 30%), low-moderate intensity exercise (SMD - 0.38 [(95%CI: (- 0.59, - 0.17)], P = 0.0005, I2 = 0%), and in non-diabetic populations (SMD - 0.36 [95%CI: (- 0.62, - 0.10)], P = 0.007, I2 = 16%). No differences were found for same-day postprandial insulin and triglycerides, and second-morning effects (postprandial or fasting glucose, insulin, and triglycerides) between different exercise patterns.

CONCLUSION

Compared with one session of continuous exercise, accumulated exercise-specifically in subgroups of PA breaks, low-moderate intensity exercises-produced greater acute effects on same-day PPG control for non-diabetic adults. There were no differences between continuous and accumulated patterns of exercise in terms of same-day postprandial insulin and triglycerides, and second-morning effects on all previously mentioned markers. The findings provide additional PA options for PPG control for individuals with limited time or exercise capacity to engage in PA in one session. Registration: PROSPERO (identification code: CRD42021251325).

Accumulating Physical Activity in Short or Brief Bouts for Glycemic Control in Adults With Prediabetes and Diabetes

Clinical practice guidelines on physical activity and diabetes currently stipulate physical activity can be accumulated in bouts of ≥10 minutes to meet recommendations for health benefits. Individuals are also encouraged to interrupt prolonged sitting with brief activity breaks of ∼1 to 5 minutes in duration. Growing research highlights accumulating activity in shorter bouts across the day as a potential strategy to improve glycemic control and to help those who are largely sedentary meet physical activity guidelines. Research has shown favourable glycemic benefits for postprandial glucose and glycated hemoglobin with either 3 short (10 to 15 minutes) or frequent brief (1 to 5 minutes) bouts of activity spread around meals or throughout the day. To date, most studies examining accumulated activity were done with people with type 2 diabetes compared with sedentary conditions, were short term and measured various indices of glycemic control using continuous glucose monitoring. The 7 trials comparing accumulating 3 short bouts to a single bout showed comparable benefits for glycemic control (i.e. fasting glucose, 24 h mean glucose and postprandial hyperglycemia). Furthermore, timing short bouts around meals may improve postprandial glucose and hyperglycemia more than a single bout. It is unknown whether a threshold for the duration of accumulated bouts exists---that is, "how much is enough?" In this narrative review, we focus on the glycemic effects of physical activity accumulated in short or brief bouts for people with prediabetes and diabetes as compared with a single continuous bout. Given that poor adherence to physical activity recommendations and that fewer opportunities exist in modern societies for incidental (nonexercise) physical activity, accumulating activity may be a choice strategy for improving glycemic control in those with and at risk of diabetes.

Multiple short bouts of exercise are better than a single continuous bout for cardiometabolic health: a randomised crossover trial

PURPOSE

To compare cardiometabolic responses to five consecutive days of daily postprandial exercise accumulated in three 10-min bouts or a single 30-min bout to a no-exercise control.

METHODS

Ten insufficiently active adults completed three trials in a randomised order. Each trial comprised five consecutive days of 30 min of exercise either accumulated in three separate 10-min bouts (ACC) after main meals; a single 30-min bout after dinner (CONT); or a no-exercise control (NOEX). Glucose regulation was assessed from an oral glucose tolerance test. Applanation tonometry was used to assess pulse wave velocity approximately 12 h following completion of the final trial.

RESULTS

Area under the 2-h glucose curve was similar for CONT (mean; 95% CI 917 mmol L^-1 2 h^-1; 815 to 1019) and ACC (931 mmol L^-1 2 h^-1; 794 to 1068, p = 0.671). Area under the 2-h insulin curve was greater following NOEX (70,328 pmol L^-1 2 h^-1; 30,962 to 109,693) than ACC (51,313 pmol L^-1 2 h^-1: 21,822 to 80,806, p = 0.007). Pulse wave velocity was lower for ACC (5.96 m s^-1: 5.38 to 6.53) compared to CONT (6.93 m s^-1: 5.92 to 7.94, p = 0.031) but not significantly lower for ACC compared to NOEX (6.52 m s^-1: 5.70 to 7.34, p = 0.151).

CONCLUSION

Accumulating 30 min of moderate-intensity walking in three bouts throughout the day is more effective at reducing markers of cardiometabolic health risk in insufficiently active, apparently healthy adults than a single daily bout. Both accumulated and single-bout walking were equally as effective at reducing postprandial glucose concentrations compared to a no-exercise control. Therefore, accumulating exercise in short bouts after each main meal might be more advantageous for overall cardiometabolic health.

Five Evidence-Based Lifestyle Habits People With Diabetes Can Use

Several evidence-based lifestyle habits focusing on the composition, timing, and sequence of meals and on pre- and postmeal exercise can improve diabetes management. Consuming low-carbohydrate, balanced meals and eating most carbohydrates early in the day are helpful habits. Eating the protein and vegetable components of a meal first and consuming the carbohydrates 30 minutes later can moderate glucose levels. Postmeal glucose surges can be blunted without precipitating hypoglycemia with moderate exercise 30-60 minutes before the anticipated peak. Short-duration, high-intensity exercise could also be effective. Premeal exercise can improve insulin sensitivity but can also cause post-exertion glucose elevations. Moreover, high-intensity premeal exercise may precipitate delayed hypoglycemia in some people. Glycemia benefits can be enhanced by eating a light, balanced breakfast after premeal exercise.

Glycemic effect of post-meal walking compared to one prandial insulin injection in type 2 diabetic patients treated with basal insulin: A randomized controlled cross-over study

Studies demonstrate that post-meal walking decreases postprandial hyperglycemia in type 2 diabetic patients but it has never been tested with the active treatment comparator. The objective of this study was to determine the effect of post-meal walking on glycemic control compared with one prandial insulin in type 2 diabetic patients who failed basal insulin. A randomized controlled cross-over study of post-meal walking or one prandial insulin was done in type 2 diabetic patients who were being treated with basal insulin between May 2017 and March 2018. In post-meal walking group, patients walked after meal for 15–20 minutes one meal a day every day for 6 weeks. In prandial insulin (basal plus) group, one prandial insulin was injected before breakfast or main meal with rapid-acting insulin. The primary outcome was a difference in HbA1c reduction in post-meal walking compared with basal plus groups. Fourteen patients completed the study. By intention-to-treat analysis, HbA1c was reduced by -0.05(range:-1.08 to 0.74) and -0.19(range:-0.8 to 0.56) % in post-meal walking and basal plus groups respectively. By per-protocol analysis, post-meal walking and basal plus groups decreased HbA1c by 0.13(range:-0.74 to 1.08) and 0.2(range:-0.56 to 0.8) %, respectively. There was were no significant differences in HbA1c reduction from baseline in each group and between groups in both intention-to-treat and per-protocol analysis. Fructosamine levels were decreased by 17.5(-59 to 43) and 10(-15 to 40) μmol/L, respectively at 3 and 6 weeks in post-meal walking group whereas the respective changes in basal plus group were 12.5(-17 to 64) and 17.5(-28 to 38) μmol/L and there were no significant differences in fructosamine reduction from baseline in each group and between groups. In conclusion, although post-meal walking might be as effective as one prandial insulin to improve glycemic control in type 2 diabetic patients who failed basal insulin but the magnitude of reduction was small. A longer-term study with a larger sample size or with a different walking protocol is required.

A comparison of acute glycaemic responses to accumulated or single bout walking exercise in apparently healthy, insufficiently active adults

OBJECTIVES

To investigate the acute glyacaemic response to accumulated or single bout walking exercise in apparently healthy adults.

DESIGN

Three arm, randomised crossover control study.

METHODS

Ten adults (age: 50±12.6 y; BMI 29.0±5.4kgm^-2) completed three separate trials comprising three 10-min walking bouts after breakfast, lunch, and dinner (APPW), a single 30-min walking bout after dinner only (CPPW), or a no-exercise control (NOEX). Participants walked on a treadmill at a moderate intensity of 55%-70% heart rate reserve. Two-hour postprandial glucose response was assessed using a continuous glucose monitor.

RESULTS

There was a difference in the pattern of the glucose response between the trials during the two hours following dinner (p<0.001). Postprandial dinner glucose concentrations were not different between APPW and CPPW but were up to 1.01mmolL^-1 lower than NOEX (partial eta²=0.21, p=0.041).

CONCLUSIONS

Ten minutes of moderate intensity walking completed 30min after each meal lowers postprandial dinner glucose concentrations in comparison to no-exercise, and reduces glucose by a similar magnitude as a single 30-min bout after the evening meal. Short bouts of exercise after each meal may be recommended to minimise glucose elevations after dinner that might increase risk of cardiometabolic disease.