Individuals with prediabetes who are overweight and obese are at an increased risk of developing endocrine disruption of fat tissue, known as adiposopathy. While short-term exercise improves adipokine profiles, the effects of exercise intensity when matched for energy expenditure on adiposopathy are unknown. We hypothesized that high-intensity exercise would elicit greater changes in adiposopathy compared to moderate exercise. Twenty-eight overweight and obese adults (age: 60.9 ± 8.4 years; BMI: 33.0 ± 5.4 kg m −2 ) with prediabetes were randomized to twelve 60-min sessions of either moderate-continuous (CONT; n = 14) or high-intensity interval (INT; n = 14) exercise training. Total and high molecular weight (HMW) adiponectin and leptin were collected to assess adiposopathy (ratio of total adiponectin to leptin; A/L). Insulin sensitivity (SI IS ) was determined using a 75 g oral glucose tolerance test before and after training.Cardiometabolic risk factors were measured and a z-score was calculated to determine metabolic syndrome (MetS) severity. CONT and INT increased A/L (P < 0.01) and decreased leptin (P < 0.01) and MetS severity (P = 0.04). Neither intervention altered circulating levels of HMW adiponectin (P = 0.76) and only INT increased total adiponectin levels (P = 0.02). Both intensities increased insulin sensitivity (P < 0.01), which was associated with improvements in A/L (r = 0.47, P = 0.01).Additionally, increases in A/L tended to relate to decreased MetS severity (r = −0.36, P = 0.09).Short-term exercise intensity, when matched for energy expenditure, does not differentially affect improvements in adiposopathy in overweight and obese adults with prediabetes. Further, 12 bouts of exercise improved insulin sensitivity and MetS severity, suggesting that improving adipokine profiles may aid in reducing cardiometabolic risk. K E Y W O R D Sadiponectin, leptin, prediabetes 1 632wileyonlinelibrary.com/journal/eph Experimental Physiology. 2020;105:632-640.

Independent of exercise dose and fat loss, short-term training improves glucose tolerance in relation to enhanced postprandial fuel use.

The objective of this study was to test if a low-calorie diet plus interval exercise (LCD+INT) improves adiposopathy, an endocrine dysfunction, when compared with an energy-deficit–matched LCD in obese women. Subjects (age: 48.2 ± 2.4 years, body mass index: 37.8 ± 1.3 kg/m2) were randomized to a 13-day LCD (n = 12; mixed meals of ∼1200 kcal/day) or LCD+INT (n = 12; 12 sessions of 60 min/day alternating 3 min at 50% and 90% peak heart rate). Exercise was estimated to expend 350 kcal per oxygen uptake–heart rate regression analysis and individuals were refed calories expended to match energy availability between groups. Absolute (post – pre caloric intake) and relative (total daily and exercise energy expenditure relative to calorie intake) energy deficits were calculated. Fitness (peak oxygen uptake) and body composition (BodPod; Cosmed USA Inc.) were measured and a 120-min, 75g oral glucose tolerance test was performed at pre- and post-intervention to assess adiposopathy (i.e., ratio of high molecular weight–adiponectin to leptin) and estimate insulin sensitivity. LCD and LCD+INT had similar absolute (P = 0.55) and relative (P = 0.76) energy deficits. LCD and LCD+INT had similar reductions in fat mass (both P < 0.001), despite LCD inducing greater weight loss (P = 0.02) than LCD+INT. Both treatments improved adiposopathy (P = 0.003) and peripheral insulin sensitivity (P = 0.02). Absolute energy deficit correlated to improved adiposopathy (r = –0.41, P = 0.05), and absolute and relative energy deficits were associated with increased insulin sensitivity (r = –0.47, P = 0.02; and r = –0.40, P = 0.05, respectively), independent of body composition changes and increased peak oxygen uptake. Taken together, LCD, with or without INT, improves adiposopathy in relation to insulin sensitivity in obese women, suggesting that a short-term energy deficit is key for reducing risk of type 2 diabetes.

No short-term exercise data exist testing whether training intensity modifies hormonal and perceived appetite in obese adults with prediabetes. Therefore, we compared the effects of short-term moderate-continuous (CONT) vs. high-intensity interval (INT) training on appetite regulation. Twenty-eight obese adults [age: 61.3 ± 1.5 yr; body mass index (BMI): 33.2 ± 1.1 kg/m2] with prediabetes were randomized to work-matched CONT ( n = 14) or INT ( n = 14) training for 2 wk. Plasma acylated ghrelin (AG), des-acylated ghrelin (dAG), active glucagon-like peptide-1 (GLP-1), and insulin were measured at 0, 30, and 60 min of a 75-g oral glucose tolerance test (OGTT) before and after training. Visual analog scales were administered at 0 and 120 min during the OGTT to examine perceived appetite. Three-day food logs were collected before and after testing to assess ad libitum diet. CONT and INT increased peak oxygen consumption ( P < 0.01) and decreased BMI ( P < 0.01). Although neither intervention altered fasting levels of AG ( P = 0.94), dAG ( P = 0.36), or insulin ( P = 0.67), CONT raised GLP-1 compared with INT ( P = 0.05). Exercise training did not affect postprandial suppression of AG ( P = 0.81) and dAG ( P = 0.67) or stimulation of GLP-1 ( P = 0.67) and insulin ( P = 0.32). Both interventions tended to decrease total energy and protein intake ( P = 0.09 and P = 0.05, respectively), despite no change in fasting hunger ( P = 0.88) and reduced perceived fullness at 120 min during the OGTT ( P = 0.05). We conclude that 2 wk of exercise training intensity does not modulate appetite-regulatory hormones in obese adults with prediabetes. Although perceived fullness to the OGTT was reduced after exercise, CONT and INT decreased energy intake, suggesting that exercise does not elicit compensatory appetite behavior to gain weight. NEW & NOTEWORTHY Adults with prediabetes are at risk for appetite dysregulation. Although exercise promotes weight management, it is unclear whether moderate-continuous or high-intensity interval training is more beneficial for appetite regulation. We show that 2 wk of exercise, independent of intensity, does not alter postprandial appetite hormones or hunger, despite slight reductions in food intake and weight. These data support exercise as an effective method to induce negative energy balance without compensatory weight gain.

Purpose People characterized as late chronotype have elevated type 2 diabetes and cardiovascular disease risk compared to early chronotype. It is unclear how chronotype is associated with insulin sensitivity, metabolic flexibility, or plasma TCA cycle intermediates concentration, amino acids (AA), and/or beta-oxidation. Methods The Morning-Eveningness Questionnaire (MEQ) was used to classify adults with metabolic syndrome (ATP III Criteria) as either early (n=15 (13F), MEQ = 64.7±1.4) or late (n=19 (16F), MEQ = 45.5±1.3) chronotype. Fasting bloods determined hepatic (HOMA-IR) and adipose insulin resistance (Adipose-IR) while a 120 min euglycemic clamp (40 mU/m 2/min, 5 mmoL/L) was performed to test peripheral insulin sensitivity (glucose infusion rate (GIR)). Carbohydrate (CHOOX) and fat oxidation (FOX) as well as non-oxidative glucose disposal (NOGD) were also estimated (indirect calorimetry). Plasma TCA intermediates, AA, and acyl-carnitines were measured along with VO2max and body composition (DXA). Results There were no statistical differences in age, BMI, fat-free mass, VO2max or ATP III criteria between groups. Early chronotype, however, had higher peripheral insulin sensitivity (P=0.009) and lower HOMA-IR (P=0.02) and Adipose-IR (P=0.05) compared to late chronotype. Further, early chronotype had higher NOGD (P=0.008) and greater insulin-stimulated CHOOX (P=0.02). While fasting lactate (P=0.01), TCA intermediates (isocitrate, ꭤ-ketoglutarate, succinate, fumarate, malate (all P≤0.04)) and some AA (proline, isoleucine (P=0.003-0.05)) were lower in early chronotype, other AA (threonine, histidine, arginine (all P≤0.05)) and most acyl-carnitines were higher (P≤0.05) compared to late chronotype. Conclusions Greater insulin sensitivity and metabolic flexibility relates to plasma TCA concentration in early chronotype.