Aims
To conduct a meta-analysis of head-to-head trials comparing aerobic exercise training of different intensities on glycemic control in type 2 diabetes.
Methods
Databases, including MEDLINE and ...EMBASE, were searched up to January 2016. Randomized trials of at least 12 weeks in duration that compared two exercise interventions of different intensities were identified. Two reviewers independently extracted data from eligible trials. Using fixed effect model, weighted mean differences (WMD) between different exercise intensities were calculated for changes in glycated hemoglobin (HbA1c) and secondary outcomes, such as fasting glucose and fasting insulin.
Results
Eight studies with a total of 235 participants were eligible. The exercise interventions lasted from 12 weeks to 6 months. The prescribed exercise intensities varied among studies. Four studies utilized vigorous exercise intensities for short durations by performing interval training. Overall, higher-intensity exercise resulted in a greater reduction in HbA1c compared to lower-intensity exercise (WMD = −0.22 %; 95 % confidence interval −0.38, −0.06; or −2.4 mmol/mol −4.15, −0.66,
I
2
= 0). Adherence to exercise and proportion of dropouts did not differ within trials. No adverse events were reported in these small trials with selected inclusion criteria.
Conclusions
Although our meta-analysis had a limited sample size, increasing exercise intensity safely accentuated reductions in HbA1c in some people with type 2 diabetes. Different approaches have been used to increase exercise intensity (i.e., some used interval training, whereas others used higher-intensity continuous exercise). However, at this time, it is unclear which form, if any, leads to the most favorable results.
Metformin and lifestyle intervention are frequently prescribed together as first-line treatments for type 2 diabetes. However, little is known about their interplay. We investigated if the effects of ...a lifestyle intervention on glycemia, body mass and cardiorespiratory fitness (CRF) were influenced by metformin therapy.
Participants randomized to intensive lifestyle intervention (ILI) or diabetes support and education (DSE) from the Look AHEAD trial were categorized into metformin therapy vs. no metformin. A two-by-two ANCOVA (i.e., metformin therapy vs. no metformin by ILI vs. DSE) was used to examine the changes in glycated hemoglobin A1C, fasting plasma glucose (FPG), body mass, and CRF over the first year post-randomization, with a primary interest in the metformin-by-lifestyle interaction effect.
Data from 1982 participants were analyzed. There was a significant metformin-by-lifestyle interaction effect on A1C (p = 0.031) and FPG (p = 0.043), resulting from larger reductions associated with metformin therapy compared to no metformin following DSE, but slightly smaller reduction associated with metformin therapy compared to no metformin following ILI. Metformin therapy was associated with smaller weight loss (−4.7 ± 6.2 vs. −5.7 ± 6.3 kg; main effect: p = 0.001) but not with differential CRF changes when compared to no metformin.
The interaction between metformin therapy and lifestyle intervention on glycemia highlights the complicated nature of combining therapies. While the small influence of background metformin therapy on intensive lifestyle intervention should not discourage the concomitant use of these therapies, our results showed that, for individuals undergoing intensive lifestyle therapy, background metformin therapy conferred little additional benefits.
•In this subsample of the Look AHEAD trial, 60% of participants were treated with metformin at baseline.•Metformin use was associated with small differences in response to intensive lifestyle interventions (ILI).•For some outcomes, such as fasting plasma glucose, those treated with metformin had slightly poorer responses to ILI.
To estimate the influence of structured prenatal exercise on newborn birth weight, macrosomia, and growth restriction.
A structured search of MEDLINE, EMBASE, CINAHL, Sport Discus, Ovid's All EBM ...Reviews, and ClinicalTrials.gov databases up to January 13, 2015. The search combined keywords and MeSH-like terms including, but not limited, to "physical activity," "exercise," "pregnancy," "gestation," "neonatal," and "randomized controlled trial."
Articles reporting randomized controlled trials comparing standard care with standard care plus supervised prenatal exercise for which birth size was available were included. Supervision was defined as at least one exercise session performed with study personnel every 2 weeks throughout the program. Interventions consisting solely of pelvic floor exercises, stretching, or relaxation were excluded. Our search yielded 1,036 publications of which 79 were assessed for eligibility. Twenty-eight studies reporting on 5,322 pregnancies were subsequently included in the analysis.
Our meta-analysis demonstrated that prenatal exercise reduced the odds of having a large newborn (birth weight greater than 4,000 g or greater than the 90th percentile for gestational age and sex) by 31% (odds ratio OR 0.69, 95% confidence interval CI 0.55-0.86; I 25%) without altering the risk of having a small newborn (birth weight less than 2,500 g or less than the 10th percentile for gestational age and sex) (OR 1.02, 95% CI 0.72-1.46; I 0%) or gestational age at delivery (weighted mean difference -0.00 weeks, 95% CI -0.09 to 0.09; I 0%). Newborns of mothers assigned to exercise were lighter than those of nonexercising controls (weighted mean difference -31 g, 95% CI -57 to -4; I 0%). Maternal gestational weight gain (weighted mean difference -1.1 kg, 95% CI -1.5 to -0.6; I 53%) and odds of cesarean delivery (OR 0.80, 95% CI 0.69-0.94; I 0%) were also reduced.
These data demonstrate that structured prenatal exercise reduces the risk of having a large newborn without a change in the risk of having a small newborn.
Exercise and diet are among the most studied behaviors that can affect blood glucose concentrations. Despite multiple studies examining these interventions in different populations and contexts, ...inconsistencies across studies have led to variable expectations. The purpose of this review is to more specifically examine how the timing of when exercise is performed in relation to meals can modify changes in glucose concentrations or insulin sensitivity. When possible, studies in type 2 diabetes are emphasized, but recent research in type 1 diabetes, obesity, and athletes is also considered.
The effect of a single bout of exercise performed after an overnight fast is often comparable to that of postprandial exercise on 24 h mean glucose concentrations. However, there is recent evidence to suggest that in some situations, but not all, longer term metabolic adaptations can be more favorable when exercise is regularly performed in the fasted state.
Exercise after an overnight fast can have different effects on glucose metabolism compared with postprandial exercise. The shorter term and longer term changes following fasting exercise can be relevant to those who are seeking greater glucoregulatory benefit from their exercise sessions, such as people with diabetes.
We examined the effects of exercise on prostate cancer-specific anxiety, fear of cancer progression, quality of life and psychosocial outcomes in patients with prostate cancer on active surveillance.
...The ERASE (Exercise during Active Surveillance for Prostate Cancer) Trial randomized 52 patients with prostate cancer undergoing active surveillance to high-intensity interval training (HIIT, 26 patients) or usual care (UC, 26 patients). The HIIT group performed a 12-week, thrice weekly, supervised, aerobic HIIT program. The UC group did not exercise. Patient-reported outcomes were assessed at baseline and after intervention, including prostate cancer-specific anxiety (Memorial Anxiety Scale for Prostate Cancer), fear of cancer progression (Fear of Cancer Recurrence Inventory), prostate cancer symptoms (Expanded Prostate Cancer Index Composite), quality of life (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core) and psychological health outcomes (eg fatigue, stress and self-esteem). Analysis of covariance was used to compare between-group differences.
Fifty of 52 participants (96%) completed patient-reported outcome assessments at 12 weeks. Adherence to HIIT was 96%. Compared to UC, HIIT significantly improved total prostate cancer-specific anxiety (adjusted between-group mean difference -2.7, 95% confidence interval, range -5.0 to -0.4, p=0.024), as well as the fear of progression subscale (p=0.013), hormonal symptoms (p=0.005), perceived stress (p=0.037), fatigue (p=0.029) and self-esteem (p=0.007).
A 12-week supervised HIIT program may improve prostate cancer-specific anxiety, fear of cancer progression, hormone symptoms, stress, fatigue and self-esteem in men with prostate cancer on active surveillance. Larger trials are needed to confirm the effects of HIIT on patient-reported outcomes in the active surveillance setting.
OBJECTIVE:To examine the influence of exercise on depressive symptoms and the prevalence of depression in the postpartum period.
DATA SOURCES:A structured search of MEDLINE, EMBASE, CINAHL, Sport ...Discus, Ovidʼs All EBM Reviews, and ClinicalTrials.gov databases was performed with dates from the beginning of the databases until June 16, 2016. The search combined keywords and MeSH-like terms including, but not limited to, “exercise,” “postpartum,” “depression,” and “randomized controlled trial.”
METHODS OF STUDY SELECTION:Randomized controlled trials comparing postpartum exercise (structured, planned, repetitive physical activity) with the standard care for which outcomes assessing depressive symptoms or depressive episodes (as defined by trial authors) were assessed. Trials were identified as prevention trials (women from the general postpartum population) or treatment trials (women were classified as having depression by the trial authors). Effect sizes with 95% confidence intervals (CIs) were calculated using Hedgesʼ g method and standardized mean differences in postintervention depression outcomes were pooled using a random-effects model.
TABULATION, INTEGRATION, AND RESULTS:Across all 16 trials (1,327 women), the pooled standardized mean difference was −0.34 (95% CI −0.50 to −0.19, I=37%), suggesting a small effect of exercise among all postpartum women on depressive symptoms. Among the 10 treatment trials, a moderate effect size of exercise on depressive symptoms was found (standardized mean difference−0.48, 95% CI −0.73 to −0.22, I=42%). In six prevention trials, a small effect (standardized mean difference−0.22, 95% CI −0.36 to −0.08, I=2%) was found. In women with depression preintervention, exercise increased the odds of resolving depression postintervention by 54% (odds ratio 0.46, Mantel-Haenszel method, 95% CI 0.25–0.84, I=0%). The trials included in this meta-analysis were small and some had methodologic limitations.
CONCLUSION:Light-to-moderate intensity aerobic exercise improves mild-to-moderate depressive symptoms and increases the likelihood that mild-to-moderate depression will resolve.
Objective:
To examine the acute and chronic effects of structured exercise on glucose outcomes assessed by continuous glucose monitors in adults with type 2 diabetes.
Methods:
PubMed, Medline, EMBASE ...were searched up to January 2020 to identify studies prescribing structured exercise interventions with continuous glucose monitoring outcomes in adults with type 2 diabetes. Randomized controlled trials, crossover trials, and studies with pre- and post-designs were eligible. Short-term studies were defined as having exercise interventions lasting ≤2 weeks. Longer-term studies were defined as >2 weeks.
Results:
A total of 28 studies were included. Of these, 23 studies were short-term exercise interventions. For all short-term studies, the same participants completed a control condition as well as at least one exercise condition. Compared to the control condition, exercise decreased the primary outcome of mean 24-h glucose concentrations in short-term studies (−0.5 mmol/L, −0.7, −0.3;
p
< 0.001). In longer-term studies, mean 24-h glucose was not significantly reduced compared to control (−0.9 mmol/L −2.2, 0.3,
p
= 0.14) but was reduced compared to pre-exercise values (−0.5 mmol/L, −0.7 to −0.2
p
< 0.001). The amount of time spent in hyperglycemia and indices of glycemic variability, but not fasting glucose, also improved following short-term exercise. Among the shorter-term studies, subgroup, and regression analyses suggested that the timing of exercise and sex of participants explained some of the heterogeneity among trials.
Conclusion:
Both acute and chronic exercise can improve 24-h glucose profiles in adults with type 2 diabetes. The timing of exercise and sex of participants are among the factors that may explain part of the heterogeneity in acute glycemic improvements following exercise.
Physical Activity and Diabetes Sigal, Ronald J.; Armstrong, Marni J.; Bacon, Simon L. ...
Canadian journal of diabetes,
April 2018, 2018-Apr, 2018-04-00, 20180401, Letnik:
42
Journal Article
Abstract Aims To compare the acute glycemic responses to a bout of high-intensity interval exercise (HIIE) and energy-matched moderate-intensity continuous exercise (MICE) performed under fasted and ...postprandial conditions. Methods A randomized, controlled, crossover design was used. Ten individuals with type 2 diabetes were each tested in five experimental conditions after an overnight fast: 1) fasted-state HIIE (HIIEfast ); 2) post-breakfast HIIE (HIIEfed ); 3) fasted-state MICE (MICEfast ); 4) post-breakfast MICE (MICEfed ); and 5) no exercise (control). MICE was performed at workload corresponding to 55% of V.V̇O2peak , whereas HIIE was composed of repetitions of three minutes at workload corresponding to 40% followed by one minute at workload corresponding to 100% V.V̇̇O2peak . Interstitial glucose was monitored by continuous glucose monitoring over 24 h under standardized diet and medication. Results Fasted-state exercise attenuated postprandial glycemic increments (p < 0.05) to a greater extent than post-breakfast exercise did. HIIE reduced nocturnal and fasting glycemia on the day following exercise more than MICE did (main effect: both p < 0.05). Compared to the control condition, HIIEfast lowered most interstitial glycemic parameters, i.e., 24-h mean glucose (− 1.5 mmol·l − 1 ; p < 0.05), fasting glucose (− 1.0 mmol·l − 1 ; p < 0.05), overall postprandial glycemic increment (− 257 mmol·360 min·l − 1 ; p < 0.05), glycemic variability (− 1.79 mmol·l − 1 ; p < 0.05), and time spent in hyperglycemia (− 283 min; p < 0.05). Conclusion This study showed that HIIE is more effective than MICE in lowering nocturnal/fasting glycemia. Exercise performed in the fasted state reduces postprandial glycemic increments to a greater extent than post-breakfast exercise does. Performing HIIE under fasted condition may be most advantageous as it lowered most aspects of glycemia.
Previous trials have evaluated the effects of aerobic training alone and of resistance training alone on glycemic control in type 2 diabetes, as assessed by hemoglobin A1c values. However, none could ...assess incremental effects of combined aerobic and resistance training compared with either type of exercise alone.
To determine the effects of aerobic training alone, resistance training alone, and combined exercise training on hemoglobin A1c values in patients with type 2 diabetes.
Randomized, controlled trial.
8 community-based facilities.
251 adults age 39 to 70 years with type 2 diabetes. A negative result on a stress test or clearance by a cardiologist, and adherence to exercise during a 4-week run-in period, were required before randomization.
Aerobic training, resistance training, or both types of exercise (combined exercise training). A sedentary control group was included. Exercise training was performed 3 times weekly for 22 weeks (weeks 5 to 26 of the study).
The primary outcome was the change in hemoglobin A1c value at 6 months. Secondary outcomes were changes in body composition, plasma lipid values, and blood pressure.
The absolute change in the hemoglobin A1c value in the combined exercise training group compared with the control group was -0.51 percentage point (95% CI, -0.87 to -0.14) in the aerobic training group and -0.38 percentage point (CI, -0.72 to -0.22) in the resistance training group. Combined exercise training resulted in an additional change in the hemoglobin A1c value of -0.46 percentage point (CI, -0.83 to -0.09) compared with aerobic training alone and -0.59 percentage point (CI, -0.95 to -0.23) compared with resistance training alone. Changes in blood pressure and lipid values did not statistically significantly differ among groups. Adverse events were more common in the exercise groups.
The generalizability of the results to patients who are less adherent to exercise programs is uncertain. The participants were not blinded, and the total duration of exercise was greater in the combined exercise training group than in the aerobic and resistance training groups.
Either aerobic or resistance training alone improves glycemic control in type 2 diabetes, but the improvements are greatest with combined aerobic and resistance training. ClinicalTrials.gov registration number: NCT00195884.
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