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Aerobic exercise (AE) and strength exercise (SE) are reported to induce discrete and specific appetite-related responses; however, the effect of combining AE and SE (i.e., combined exercise; CE) remains relatively unknown. Twelve inactive overweight men (age: 48 ± 5 y; BMI: 29.9 ± 1.9 kg⋅m²) completed four conditions in a random order: 1) nonexercise control (CON) (50 min seated rest); 2) AE (50 min cycling; 75% VO2peak); 3) SE (10 x 8 leg extensions; 75% 1RM); and 4) CE (50% SE + 50% AE). Perceived appetite, and appetite-related peptides and metabolites were assessed before and up to 2 h postcondition (0P, 30P, 60P, 90P, 120P). Perceived appetite did not differ between trials (p < .05). Acylated ghrelin was lower at 0P in AE compared with CON (p = .039), while pancreatic polypeptide (PP) was elevated following AE compared with CON and CE. Glucose-dependent insulinotropic peptide (GIPtotal) was greater following all exercise conditions compared with CON, as was glucagon, although concentrations were generally highest in AE (p < .05). Glucose was acutely increased with SE and AE (p < .05), while insulin and C-peptide were higher after SE compared with all other conditions (p < .05). In inactive, middle-aged men AE, SE and CE each have their own distinct effects on circulating appetite-related peptides and metabolites. Despite these differential exercise-induced hormone responses, exercise mode appears to have little effect on perceived appetite compared with a resting control in this population. [ABSTRACT FROM AUTHOR]

This preliminary study aimed to investigate the effect of exercise on appetite and mood following multiple days of sleep disruption (restriction [RES], fragmentation [FRAG]) or sleep extension (EXT), compared to normal sleep (CONT) in inactive, middle‐aged men. Nine men completed four randomised trials initiated by 3 nights (day 1–3) of CONT (6.5–8 hr), RES (4 hr), FRAG (6.5–8 hr, interrupted at 2‐hr intervals) or EXT (10 hr). On day 4 between 08:30 and 11:00 hours, perceived appetite, food cravings, appetite‐related hormones (acylated ghrelin, leptin, peptide tyrosine–tyrosine [PYY]total), glucose, mood states and wellness (stress, fatigue, soreness, and mood) were assessed before (post‐sleep manipulation [SM]) and after (post‐exercise [EX]) a 20‐min vigorous cycling bout (rating of perceived exertion: 15). There was no effect of sleep manipulation or exercise on perceived appetite (p =.34–.62). Some aspects of food craving were altered after RES and EXT, with vigorous exercise attenuating the desire for sweet foods in RES (p =.12). PYYtotal was lower after RES compared to EXT and FRAG (p =.03), but was unaltered by exercise (p =.03). Ghrelin was higher for RES and EXT compared to CONT and FRAG after exercise (p =.001–.03). Total wellness was reduced and total mood disturbance (TMD) was higher after RES and FRAG compared to CONT and EXT (p ≤.05). However, vigorous exercise countered these changes, with wellness and TMD remaining significantly impaired for FRAG compared to EXT only at this time (p =.02–.03). Vigorous exercise mitigates some aspects of food cravings and counters the impaired mood states that exist after multiple days of restricted and fragmented sleep. [ABSTRACT FROM AUTHOR]

New Findings: What is the central question of this study?What are the interactions between sleep and appetite following early evening high‐intensity interval exercise (HIIE)?What is the main finding and its importance?HIIE can be performed in the early evening without subsequent sleep disruptions and may favourably alter appetite‐related hormone concentrations. Nonetheless, perceived appetite and energy intake do not change with acute HIIE regardless of time of day. Despite exercise benefits for sleep and appetite, due to increased time restraints, many adults remain inactive. Methods to improve exercise compliance include preferential time‐of‐day or engaging in short‐duration, high‐intensity interval exercise (HIIE). Hence, this study aimed to compare effects of HIIE time‐of‐day on sleep and appetite. Eleven inactive men undertook sleep monitoring to determine baseline (BASE) sleep stages and exclude sleep disorders. On separate days, participants completed 30 min HIIE (60 s work at 100% V̇O2 peak , 240 s rest at 50% V̇O2 peak) in (1) the morning (MORN; 06.00–07.00 h), (2) the afternoon (AFT; 14.00–16.00 h) and (3) the early evening (EVEN: 19.00–20.00 h). Measures included appetite‐related hormones (acylated ghrelin, leptin, peptide tyrosine tyrosine) and glucose pre‐exercise, 30 min post‐exercise and the next morning; overnight polysomnography (PSG; sleep stages); and actigraphy, self‐reported sleep and food diaries for 48 h post‐exercise. There were no between‐trial differences for total sleep time (P = 0.46). Greater stage N3 sleep was recorded for MORN (23 ± 7%) compared to BASE (18 ± 7%; P = 0.02); however, no between‐trial differences existed (P > 0.05). Rapid eye movement (REM) sleep was lower and non‐REM sleep was higher for EVEN compared to BASE (P ≤ 0.05). At 30 min post‐exercise, ghrelin was higher for AFT compared to MORN and EVEN (P = 0.01), while glucose was higher for MORN compared to AFT and EVEN (P ≤ 0.02). No between‐trial differences were observed for perceived appetite (P ≥ 0.21) or energy intake (P = 0.57). Early evening HIIE can be performed without subsequent sleep disruptions and reduces acylated ghrelin. However, perceived appetite and energy intake appear to be unaffected by HIIE time of day. [ABSTRACT FROM AUTHOR]