The effect of 10 days of energy-deficit diet and high-intensity exercise training on the plasma high-density-lipoprotein (HDL) level among healthy collegiate males.

An energy-deficit (ED) diet increases lipid mobilisation, while endurance exercise improves lipid profile by promoting formation of high-density lipoproteins (HDLs) among moderately active population. However, it is not clear whether ED with high-intensity exercise training can improve lipid profiles. Therefore, 20 recreationally active males (20.3 ± 2.7 years old with peak oxygen consumption (Opeak) of 2.8 ± 0.2 L min) with HDL concentration of 1.44 ± 0.32 mmol L, were evenly allocated to either an ED group (1590 ± 79 kcal day: 40% of total caloric omitted at lunchtime) or a control (CON) group (2570 ± 139 kcal day). Participants in both groups performed high-intensity cycling at 90% Opeak at a constant workload for 8 min, 2 h after breakfast on day D, D, D, D, D and D (D is day number), after which blood samples were collected. In ED, compared to D, triglycerides (TG) decreased on D ( < .01) while total low-density lipoprotein (LDL), total cholesterol (TC) increased on D, while HDL progressively increased on D ( = .01) with a final value of 1.67 ± 0.24 mmol L. In CON, there were no changes in TG, TC and HDL while LDL was reduced on D ( = .01). Moreover, the proportions of TC/HDL and LDL/HDL increased in ED on D and D ( = .05), respectively, while LDL/HDL in CON was reduced on D ( = .01). In brief, 10 days of ED and a series of high-intensity exercise sessions show progressive elevation of HDL which suggest longer period is required to observe changes in lipid ratios.