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N G Boulé

Publications and source records attributed to N G Boulé.

4 recordsLinked to original sources

Meta-analysis of the effect of structured exercise training on cardiorespiratory fitness in Type 2 diabetes mellitus.

AIMS/HYPOTHESIS: Low cardiorespiratory fitness is a powerful and independent predictor of mortality in people with diabetes. Several studies have examined the effects of exercise on cardiorespiratory fitness in Type 2 diabetic individuals. However, these studies had relatively small sample sizes and highly variable results. Therefore the aim of this study was to systematically review and quantify the effects of exercise on cardiorespiratory fitness in Type 2 diabetic individuals. METHODS: MEDLINE, EMBASE, and four other databases were searched up to March 2002 for randomized, controlled trials evaluating effects of structured aerobic exercise interventions of 8 weeks or more on cardiorespiratory fitness in adults with Type 2 diabetes. Cardiorespiratory fitness was defined as maximal oxygen uptake (VO(2max)) during a maximal exercise test. RESULTS: Seven studies, presenting data for nine randomized trials comparing exercise and control groups (overall n=266), met the inclusion criteria. Mean exercise characteristics were as follows: 3.4 sessions per week, 49 min per session for 20 weeks. Exercise intensity ranged from 50% to 75% of VO(2max). There was an 11.8% increase in VO(2max) in the exercise group and a 1.0% decrease in the control group (post intervention standardized mean difference =0.53, p<0.003). Studies with higher exercise intensities tended to produce larger improvements in VO(2max). Exercise intensity predicted post-intervention weighted mean difference in HbA(1c) (r=-0.91, p=0.002) to a larger extent than did exercise volume (r=-0.46, p=0.26). CONCLUSIONS/INTERPRETATION: Regular exercise has a statistically and clinically significant effect on VO(2max) in Type 2 diabetic individuals. Higher intensity exercise could have additional benefits on cardiorespiratory fitness and HbA(1c).

Databases, Factual↗

Insulin resistance and abdominal adiposity in young men with documented malnutrition during the first year of life.

OBJECTIVE: The main objective of the study was to examine the effect of early life malnutrition on the relation between insulin sensitivity and abdominal adiposity in adulthood. It was hypothesised that participants with early life malnutrition would display a more pronounced deterioration of insulin sensitivity in association with a gain in abdominal fat. DESIGN: As a first attempt to investigate this issue, we studied the effect of body fat gains in a cross-sectional context. SUBJECTS: A total of 26 young adult men with evidence of malnutrition during the first year of life and 27 control subjects were recruited for this study. Malnutrition status was determined from medical files of paediatric hospitals in the Mexico City metropolitan area. MEASUREMENTS: Insulin sensitivity was measured by hyperinsulinaemic euglycaemic clamp, and body composition was measured by anthropometrics, bioelectrical impedance and computed tomography. RESULTS: There was a negative correlation between total abdominal adipose tissue area and insulin sensitivity in the previously malnourished and control groups (r(2)=0.65 and 0.35, P<0.01, respectively). When matched for low amounts of abdominal fat (114 cm(2)), participants with and without early life malnutrition had similar insulin sensitivity (9.03 vs 8.88 mg kg(-1) x min(-1)). However, when matched for high amounts of abdominal fat (310 cm(2)) participants who were malnourished during the first year of life had lower insulin sensitivity (4.74 vs 6.85 mg kg(-1) x min(-1), P<0.05). CONCLUSION: Higher levels of abdominal adipose tissue are more detrimental to insulin sensitivity in previously malnourished individuals.

Abdomen↗

Effects of exercise on glycemic control and body mass in type 2 diabetes mellitus: a meta-analysis of controlled clinical trials.

CONTEXT: Exercise is widely perceived to be beneficial for glycemic control and weight loss in patients with type 2 diabetes. However, clinical trials on the effects of exercise in patients with type 2 diabetes have had small sample sizes and conflicting results. OBJECTIVE: To systematically review and quantify the effect of exercise on glycosylated hemoglobin (HbA(1c)) and body mass in patients with type 2 diabetes. DATA SOURCES: Database searches of MEDLINE, EMBASE, Sport Discuss, Health Star, Dissertation Abstracts, and the Cochrane Controlled Trials Register for the period up to and including December 2000. Additional data sources included bibliographies of textbooks and articles identified by the database searches. STUDY SELECTION: We selected studies that evaluated the effects of exercise interventions (duration >/=8 weeks) in adults with type 2 diabetes. Fourteen (11 randomized and 3 nonrandomized) controlled trials were included. Studies that included drug cointerventions were excluded. DATA EXTRACTION: Two reviewers independently extracted baseline and postintervention means and SDs for the intervention and control groups. The characteristics of the exercise interventions and the methodological quality of the trials were also extracted. DATA SYNTHESIS: Twelve aerobic training studies (mean [SD], 3.4 [0.9] times/week for 18 [15] weeks) and 2 resistance training studies (mean [SD], 10 [0.7] exercises, 2.5 [0.7] sets, 13 [0.7] repetitions, 2.5 [0.4] times/week for 15 [10] weeks) were included in the analyses. The weighted mean postintervention HbA(1c) was lower in the exercise groups compared with the control groups (7.65% vs 8.31%; weighted mean difference, -0.66%; P<.001). The difference in postintervention body mass between exercise groups and control groups was not significant (83.02 kg vs 82.48 kg; weighted mean difference, 0.54; P =.76). CONCLUSION: Exercise training reduces HbA(1c) by an amount that should decrease the risk of diabetic complications, but no significantly greater change in body mass was found when exercise groups were compared with control groups.

Adult↗

Increasing exercise duration does not affect the postexercise elevation in esophageal temperature.

It has previously been observed that (a) following 15 min of intense exercise, esophageal temperature (Tes) remains elevated at a plateau value equal to that at which active vasodilation had occurred during exercise (i.e., esophageal temperature threshold for cutaneous vasodilation [ThVD]); and (b) exercise/recovery cycles of identical intensity and duration, when sequential, result in progressively higher Tes at the beginning and end of exercise. In the latter case, parallel increases in both the exercise ThVD and postexercise plateau of Tes were noted. This study was conducted to determine if the elevated postexercise Tes is related to increases in whole-body heat content. On separate occasions, 9 subjects completed 3 bouts of treadmill exercise at 70% VO2 max, 29 degrees C ambient temperature. Each exercise bout lasted either 15, 30, or 45 min and was followed by 60 min of inactive recovery. Esophageal temperatures were similar at the start of each exercise bout, but the rise in Tes during exercise nearly doubled from 1.0 degree C after 15 min of exercise to 1.9 degrees C after 45 min of exercise. There were no intercondition differences among the exercise ThVD (approximately 0.36 degree C above baseline) or postexercise plateau values for Tes (approximately 0.40 degree C above baseline). Thus the relationship between the ThVD during exercise and the postexercise Tes did not appear to be dependent on changes in whole-body heat content as produced by endogenous heating during exercise of different duration.

Adult↗