The Role of Exercise and Physical Activity in Weight Loss and Maintenance

This review explores the role of physical activity (PA) and exercise training (ET) in the prevention of weight gain, initial weight loss, weight maintenance, and the obesity paradox. In particular, we will focus the discussion on the expected initial weight loss from different ET programs, and explore intensity/volume relationships. Based on the present literature, unless the overall volume of aerobic ET is very high, clinically significant weight loss is unlikely to occur. Also, ET also has an important role in weight regain after initial weight loss. Overall, aerobic ET programs consistent with public health recommendations may promote up to modest weight loss (~ 2 kg), however the weight loss on an individual level is highly heterogeneous. Clinicians should educate their patients on reasonable expectations of weight loss based on their physical activity program and emphasize that numerous health benefits occur from PA programs in the absence of weight loss.     

Micronutrients and Dengue

Dengue virus infection is the most widespread mosquito-borne viral infection in humans and has emerged as a serious global health challenge. In the absence of effective treatment and vaccine, host factors including nutritional status, which may alter disease progression, need investigation. The interplay between nutrition and other infections is well-established, and modulation of nutritional status often presents a simple low-cost method of interrupting transmission, reducing susceptibility, and/or ameliorating disease severity. This review examines the evidence on the role of micronutrients in dengue virus infection. We found critical issues and often inconsistent results across studies; this finding along with the lack of sufficient literature in this field have limited our ability to make any recommendations. However, vitamins D and E have shown promise in small supplementation trials. In summary, the role of micronutrients in dengue virus infection is an exciting research area and needs to be examined in well-designed studies with larger samples.     

A Phase One Safety Study of Lactobacillus reuteri Conducted in the Peruvian Amazon: Observations from the Field

Recently, an association between childhood growth stunting and aflatoxin (AF) exposure has been identified. In Ghana, homemade nutritional supplements often consist of AF-prone commodities. In this study, children were enrolled in a clinical intervention trial to determine the safety and efficacy of Uniform Particle Size NovaSil (UPSN), a refined calcium montmorillonite known to be safe in adults. Participants ingested 0.75 or 1.5 g UPSN or 1.5 g calcium carbonate placebo per day for 14 days. Hematological and serum biochemistry parameters in the UPSN groups were not significantly different from the placebo-controlled group. Importantly, there were no adverse events attributable to UPSN treatment. A significant reduction in urinary metabolite (AFM₁) was observed in the high-dose group compared with placebo. Results indicate that UPSN is safe for children at doses up to 1.5 g/day for a period of 2 weeks and can reduce exposure to AFs, resulting in increased quality and efficacy of contaminated foods.     

Antecedent hypoglycaemia does not diminish the glycaemia-increasing effect and glucoregulatory responses of a 10 s sprint in people with type 1 diabetes

Aims/hypothesis

A 10 s sprint has been reported to provide a means to prevent acute post-exercise hypoglycaemia in young adults with type 1 diabetes because of its glycaemia-raising effect, but it is unclear whether this effect is impaired by antecedent hypoglycaemia. The purpose of this study was to investigate whether antecedent hypoglycaemia impairs the glycaemia-raising effect of a 10 s sprint in individuals with type 1 diabetes.

Methods

Eight individuals underwent a hyperinsulinaemic–hypoglycaemic or hyperinsulinaemic–euglycaemic clamp on two separate mornings. Thereafter, the participants underwent a basal insulin–euglycaemic clamp before performing a 10 s sprint on a cycle ergometer. The levels of blood glucose and glucoregulatory hormones and rates of glucose appearance (Ra) and disappearance (Rd) were compared between conditions.

Results

During the morning clamps, blood glucose levels were significantly different between conditions of hypoglycaemia (2.8?±?0.1 mmol/l) and euglycaemia (5.4?±?0.2 mmol/l; p?<?0.001). Mean glycaemia prior to sprinting was similar (5.6?±?0.4 and 5.5?±?0.3 mmol/l for hypoglycaemic and euglycaemic conditions, respectively; p?=?0.83). In response to the afternoon sprint, the pattern of increase in blood glucose levels did not differ between conditions, reaching similar maximal levels 45 min after exercise (6.5?±?0.4 and 6.6?±?0.3 mmol/l, respectively; p?=?0.43). The early post-exercise patterns in glucose Ra and Rd and increases in plasma adrenaline (epinephrine), growth hormone and cortisol levels did not differ between conditions.

Conclusions/interpretation

Hypoglycaemia in the morning does not diminish the glycaemia-raising effect of an afternoon 10 s sprint in young adults with type 1 diabetes, suggesting that sprinting is a useful strategy for opposing hypoglycaemia, regardless of prior hypoglycaemia.