Cardiorespiratory Responses during Aquatic Treadmill Exercise and Land Treadmill Exercise in Adults with Diabetes

The purpose of this study was to compare the effect of aquatic treadmill (ATM) exercise to land treadmill (LTM) exercise in adults with type 2 diabetes. Five participants with type 2 diabetes (T2D group; 4 females, 1 male; age = 51±6 years; height = 170±7 cm; weight = 96±24 kg; body fat = 31.6±2.2%) and five participants without type 2 diabetes (control group; 4 females, 1 male; age = 51±6 years; height = 170±6 cm; weight = 71±15 kg; body fat = 26.8±4.6%) completed the study. Protocols for both ATM exercise and LTM exercise began at 2 mph with 0% grade and increased by 1 mph after 5 minutes at each stage. Termination occurred after participants completed the protocol or reached 85% of heart rate reserve. Heart rate, absolute and relative VO2, and systolic and diastolic blood pressure were measured at rest and during steady-state exercise at each intensity. Mean arterial pressure (MAP) was calculated. A 2 x 2 x 3 Mixed Factorial ANOVA and Bonferroni post hoc test with a significance level of .0125 were used. There was a significant difference (p2 of the two groups at 4 mph while performing the land treadmill exercise (T2D: 14.1±1.4 ml/kg/min vs. control: 18.4±1.6 ml/kg/min, p2 between participant groups or modes of exercise. Those with type 2 diabetes had an increased MAP versus those without type 2 diabetes while performing the land treadmill exercise at 2 mph (T2D: 93±3 mmHg vs. control: 81±5 mmHg, p2, and MAP respond similarly in both groups during ATM and LTM exercise at most treadmill speeds

The Dose Effect of Whey Protein on Insulin Responses in Pre-Diabetics and Type 2 Diabetics

People with pre-diabetes and type 2 diabetes have shown an increase in insulin secretion after ingesting 55 g of whey protein coupled with a glycemic challenge. However, the effect of lower amounts of whey protein on insulin responses remains unclear. Our hypothesis was that both 20 g and 30 g of whey consumption prior to an oral glucose tolerance test (OGTT) would produce an increase in insulin secretion, with 30 g producing the greatest increase compared to a control. PURPOSE: The purpose of this study was to examine the effect of two different doses of whey protein ingested 30 min prior to a 50 g OGTT on glucose, insulin, C-peptide, and glucagon responses. METHODS: Diabetic or pre-diabetic participants (n=9, mean ± SD; age: 64.3 + 8.1 yrs; BMI: 29.4 + 6.0 kg/m2; body fat percentage: 42.5 + 7.8 %; fasting plasma glucose: 6.9 + 1.2 mmol/l; HbA1c: 6.4 + 0.6 %) completed three trials. The randomly assigned trials consisted of: 250 ml of water (CON), 250 ml of water + 20 g whey (20g), and 250 ml of water + 30 g whey (30g), followed by an OGTT. Blood was collected at -30, 0, 15, 30, 60, 90, 120, and 150 min for the measurement of glucose, insulin, C-peptide, and glucagon. The whey protein mixture was administered immediately following the -30 min blood draw, and the 50 g OGTT began immediately following the 0 min blood draw. Glucose was analyzed using a YSI 2900D glucose analyzer and insulin, C-peptide, and glucagon were measured via multiplex fluorescent detection (MagPix). A one-way repeated measures ANOVA (pRESULTS: Incremental area under the curve (AUC) for glucose presented no difference between the 3 trials. Insulin AUC was significantly increased from CON to 20g (p=0.004, 36.3%), CON to 30g (p=0.002, 61.7%), and 20g to 30g (p=0.030, 18.6%). C-peptide and glucagon AUC significantly increased from CON to 20g (p=0.018, 20.6%; p=0.046, 33.1%) and CON to 30g (p=0.001, 30.1%; p=0.017, 33.7%). CONCLUSION: Whey protein elicited a dose response on plasma insulin, increasing concentrations from CON to 20g, and 20g to 30g, however plasma glucose was unaffected. 20g and 30g displayed similar responses for glucagon. Neither 20 g nor 30 g of whey protein may be adequate to provide glycemic improvement in the disease management of type 2 or pre-diabetes