Cycling exercise initiated early in pregnancy and performed at least 30 minutes, 3 times per week, is associated with a significant reduction in the frequency of gestational diabetes mellitus in overweight/obese pregnant women. And this effect is very relevant to that exercise at the beginning of pregnancy decreases the gestational weight gain before the mid-second trimester. Furthermore, there was no evidence that the exercise prescribed in this study increased the risk of preterm birth or reduced the mean gestational age at birth.

High-intensity intermittent exercise suppresses subsequent ad-libitum energy intake in overweight inactive men. This format of exercise was found to be well tolerated in an overweight population.

OBJECTIVE -To compare the response of blood glucose levels to intermittent highintensity exercise (IHE) and moderate-intensity exercise (MOD) in individuals with type 1 diabetes. RESEARCH DESIGN AND METHODS-Seven healthy individuals with type 1 diabetes were tested on two separate occasions, during which either a 30-min MOD or IHE protocol was performed. MOD consisted of continuous exercise at 40% VO 2peak , while the IHE protocol involved a combination of continuous exercise at 40% VO 2peak interspersed with 4-s sprints performed every 2 min to simulate the activity patterns of team sports.RESULTS -Both exercise protocols resulted in a decline in blood glucose levels. However, the decline was greater with MOD (Ϫ4.4 Ϯ 1.2 mmol/l) compared with IHE (Ϫ2.9 Ϯ 0.8 mmol/l; P Ͻ 0.05), despite the performance of a greater amount of total work with IHE (P Ͻ 0.05). During 60 min of recovery from exercise, glucose levels remained higher in IHE compared with MOD (P Ͻ 0.05). Furthermore, glucose levels remained stable during recovery from IHE, while they continued to decrease after MOD (P Ͻ 0.05). The stabilization of blood glucose levels with IHE was associated with elevated levels of lactate, catecholamines, and growth hormone during early recovery from exercise (P Ͻ 0.05). There were no differences in free insulin, glucagon, cortisol, or free fatty acids between MOD and IHE.CONCLUSIONS -The decline in blood glucose levels is less with IHE compared with MOD during both exercise and recovery in individuals with type 1 diabetes. Diabetes Care 28:1289 -1294, 2005E xercise is generally recommended for individuals with type 1 diabetes for the same reasons as the rest of the population. That is, regular physical activity has physiological benefits, including improved physical work capacity, body composition, blood pressure, and blood lipid profile (1-3) and is associated with less risk of diabetes complications and mortality in individuals with type 1 diabetes (4). In addition, exercise has psychological benefits, including increased sense of well-being, quality of life, and ability to cope with stress (3). Particularly in children, participation in sports is an important recreational and social activity that benefits both social interaction and peer group assimilation (5).Unfortunately, participation in exercise can also increase the risk of experiencing hypoglycemia in individuals with type 1 diabetes, both during exercise (6,7) and for up to 31 h of recovery (8). Consequently, many individuals with type 1 diabetes feel negatively toward physical activity (9) and are discouraged from participating in sports and games by their parents, school staff, or physicians (10).Existing guidelines to minimize the risk of hypoglycemia associated with exercise are often general (11) and fail to take into account that different precautions are required for exercise of varying type, duration, and intensity. Specifically, there are no evidence-based guidelines for individuals wanting to participate in intermittent high-intensity exercise (IHE...

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The effect of duration-matched concurrent exercise training (CET) (50% resistance (RET) and 50% endurance (EET) training) on physiological training outcomes in untrained middle-aged men remains to be elucidated. Forty-seven men (age, 48.1 ± 6.8 years; body mass index, 30.4 ± 4.1 kg·m(-2)) were randomized into 12-weeks of EET (40-60 min of cycling), RET (10 exercises; 3-4 sets × 8-10 repetitions), CET (50% serial completion of RET and EET), or control condition. The following were determined: intervention-based changes in fitness and strength; abdominal visceral adipose tissue (VAT), total body fat (TB-FM) and fat-free (TB-FFM) mass; plasma cytokines (C-reactive protein (CRP), tumor necrosis factor-α (TNFα) interleukin-6 (IL-6)); muscle protein content of p110α and glucose transporter 4 (GLUT4); mRNA expression of GLUT4, peroxisome proliferator-activated receptor-γ coactivator-1α-β, cytochrome c oxidase, hexokinase II, citrate synthase; oral glucose tolerance; and estimated insulin sensitivity. CET promoted commensurate improvements of aerobic capacity and muscular strength and reduced VAT and TB-FM equivalently to EET and RET (p < 0.05), yet only RET increased TB-FFM (p < 0.05). Although TNFα and IL-6 were reduced after all training interventions (p < 0.05), CRP remained unchanged (p > 0.05). EET reduced area under the curve for glucose, insulin, and C-peptide, whilst CET and RET respectively reduced insulin and C-peptide, and C-peptide only (p < 0.05). Notwithstanding increased insulin sensitivity index after all training interventions (p < 0.05), no change presented for GLUT4 or p110α total protein, or chronic mRNA expression of the studied mitochondrial genes (p > 0.05). In middle-aged men, 12 weeks of duration-matched CET promoted commensurate changes in fitness and strength, abdominal VAT, plasma cytokines and insulin sensitivity, and an equidistant glucose tolerance response to EET and RET; despite no change of measured muscle mechanisms associative to insulin action, glucose transport, and mitochondrial function.